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How do you treat ground-glass opacities?

Treatment of GGNs – The current recommendation for the treatment of GGNs is resection. However, the criteria for surgery vary among different guidelines. Results of recent studies indicate the importance of the presence and size of a solid component, of which are known to reflect the pathologically invasive component of adenocarcinoma ( 24 ). According to the recent Fleischner Society guidelines, resection is recommended for pure GGNs that grow or show the development of solid portions as well as for persistent part-solid nodules with solid portions of ≥6 mm ( 20 ). The guidelines of the American College of Chest Physicians recommend that GGNs that meet any of the following conditions should be resected: (I) GGNs with growth or development of new solid components, (II) pure GGNs >10 mm with confirmed persistence, (III) part-solid GGNs >8 mm with confirmed persistence, and (IV) part-solid GGNs >15 mm without any follow-up ( 25 ). However, there is no generally accepted consensus regarding the optimal timing of surgery when GGNs show growth. Accordingly, it is still questionable whether urgent surgery is necessary for all such GGNs. Considering the commonly indolent course of GGNs even after the start of growth and the relatively low mortality of lung cancers presenting as GGNs compared to solid cancers ( 26 ), the life expectancy of patients with other medical conditions and the possibility of surgery-related complications should be considered. The introduction of video-assisted thoracoscopic surgery has resulted in significant advances in the field of management of pulmonary nodules including GGNs. Currently, lobectomy is the modality of choice for resection of early lung cancer. A recent prospective study from the Japan Clinical Oncology Group revealed that the 5-year overall and relapse-free survival rates of patients who received lobectomy and lymph node dissection were 90.6% and 84.7%, respectively ( 27 ). Recently, the use of limited resection such as segmentectomy or wide-wedge resection is increasing. Promising results have been reported regarding the performance of limited resection for relatively smaller GGNs that had outcomes similar to those of standard lobectomy ( 28 ). However, as limited resection is often associated with a higher recurrence rate for certain subtypes of early lung adenocarcinomas ( 29 ), lobectomy should be indicated for GGNs with a significant solid component; in addition, careful selection of patients who can undergo limited resection for GGNs is essential. Stereotactic body radiation therapy (SBRT) and percutaneous ablation could be other options for local treatment of GGNs considered for resection. The study by Hammer et al. evaluated a simulation model for the treatment of GGNs with SBRT in patients aged >77 years, instead of lobectomy ( 23 ). The results revealed that, among patients who developed nodules that require treatment, the overall survival was higher for those treated with SBRT (80%) than for those treated with surgery (79%) and for those with no therapy (74%). However, as the authors noted, we should take into account the fact that only a minority of GGNs had clinically significant malignancy in the study. Therefore, the mortality outcomes would have been driven not by recurrence but rather by treatment-related complication rates, which are higher for lobectomy than for SBRT. To date, there are limited data about the outcomes of SBRT or percutaneous ablation compared to lobectomy or limited resection for the treatment of early lung cancer. Unfortunately, 2 prospective studies that compared the outcomes of surgery and SBRT for early lung cancers were closed owing to slow accrual ( 30 ). Therefore, in future, the effects of treatment modalities need to be evaluated in real-world clinical settings rather than simulation models. To achieve this goal, large randomized prospective trials are needed. Another important limitation of SBRT and percutaneous ablation is that the pathologic results of the treated GGNs cannot be obtained, in contrast to resection, which can be used to perform the pathologic diagnosis and treatment simultaneously. This fact should be considered by corresponding clinicians because most patients with GGNs undergo resection without prior pathologic confirmation. Regarding the proper management of GGNs, the multiplicity is also an important issue that should be taken into account. Approximately one-third of patients with GGNs have multiple nodules, which are usually similar in size and observed in different lobes. Generally, multiple GGNs are considered to be multiple synchronous lung cancer rather than a metastatic disease. A study by our group that investigated the genetic features of multiple GGNs resected from the same patients showed that a high frequency of discordant EGFR mutations (17 of 24, 70.8%) could discriminate tumor clonalities (18 of 24, 75%) of multiple neoplastic GGNs ( 31 ). Accordingly, multiple GGNs should be treated as independent early lung cancers if they fulfill the criteria for resection, and such patients would have a high probability of undergoing multiple resection of the lungs. In these patients, initial resection of GGNs with limited resection can be an effective strategy to preserve the remnant pulmonary function. Non-surgical treatments such as SBRT or percutaneous ablation can be alternative options for patients with a high risk of complications or those who cannot undergo surgery. In conclusion, despite the relatively long and indolent course, GGNs are generally heterogeneous, thereby making it difficult to predict the growth or development of a solid portion requiring treatment. In particular, a notable percentage of GGNs tend to grow even after a long time of stabilization. Therefore, understanding the distinct etiology—including the genetic features—along with more cumulative data on the long-term follow-up of such GGNs would allow the development of novel management strategies. In addition, future studies should focus on the selection of the GGNs for invasive treatment, while considering the timing and modality of therapy, especially in patients with multiple nodules. The relevant data regarding these issues would be essential for the optimal management of pulmonary GGNs.

Can ground-glass opacities improve?

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• Diagnostic performance of percutaneous core needle lung biopsy under multi-CT fluoroscopic guidance for ground-glass opacity pulmonary lesions.
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A clinicopathological study of resected adenocarcinoma 2 cm or less in diameter. Ann Thorac Surg 2004; 78 :1011-6.25. Suzuki K, Kusumoto M, Watanabe S, et al. Radiologic classification of small adenocarcinoma of the lung: radiologic-pathologic correlation and its prognostic impact. Ann Thorac Surg 2006; 81 :413-9.26.

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The proportion of consolidation to ground-glass opacity on high resolution CT is a good predictor for distinguishing the population of non-invasive peripheral adenocarcinoma. Lung Cancer 2003; 42 :303-10.30. Suzuki K, Koike T, Asakawa T, et al. A prospective radiological study of thin-section computed tomography to predict pathological noninvasiveness in peripheral clinical IA lung cancer (Japan Clinical Oncology Group 0201).

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Ground-glass opacity lesions on computed tomography during postoperative surveillance for primary non-small cell lung cancer. Lung Cancer 2012; 76 :56-60.36. Silva M, Sverzellati N, Manna C, et al. Long-term surveillance of ground-glass nodules: evidence from the MILD trial. J Thorac Oncol 2012; 7 :1541-6.37.

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Can ground-glass opacity disappear?

Ground-glass opacities (GGO) are seen mostly in patients with moderate to severe respiratory conditions and those infected with COVID-19. Ground-glass opacities (GGO) are gray areas that computed tomography scans or X-rays of the lungs pick up. The normal lungs appear black in such scans.

GGOs can be seen mostly in patients with moderate to severe respiratory conditions, such as infections, cancers, and inflammation. Recently, ground-glass opacities were seen in most patients infected with COVID-19, They helped classify the lung involvement in these cases. Ground-glass opacities are usually benign and resolve spontaneously without any complications in patients with short-term illnesses.

Most of these patients may not even know that it is present. Others may complain of cough, tiredness, and shortness of breath, The presence of GGOs in chest scans could indicate:

Fluid, pus, or cells in air sacs Thickening of walls of air sacs Interstitial thickening (thickening of lung tissue) Inflammation Pulmonary edema Damage to blood vessels and hemorrhage Cancerous growths Fibrosis

How do you treat lung opacities?

Even though over 80 million people undergo computed tomography (CT) scans each year in the United States, some of the words and phrases related to this imaging test can be complicated and hard to understand. For example, one term that healthcare professionals might use in reference to a lung CT scan is “opacity.” This is a radiological term that refers to the hazy gray areas on images made by CT scans or X-rays.

This article will provide information about lung opacity, whether it means you have lung cancer, and what the outlook may be for those with lung opacity. Ground-glass opacity is a radiological term that refers to hazy gray areas on the images made by CT scans or X-rays. It indicates increased density in these areas.

Typically, the lungs appear black on a CT scan or X-ray. This shows that they are free of blockages. When gray areas are visible instead, it means that something is partially filling this area inside the lungs. These gray areas are referred to as ground-glass opacity.

fluid, pus, or cells filling the air spacewalls of the alveoli thickeningspace between the lungs thickening

Ground-glass opacity can result from a variety of causes, according to 2020 research, Sometimes it is temporary and the result of a short-term illness. In other cases, it can signify a chronic or more serious condition. Ground-glass opacity can also indicate an infection or other inflammatory process, which is usually what a clinician will share with you or your loved one who has had a CT scan or X-ray.

shortness of breathpersistent coughing coughing with yellow, green, or bloody mucuschest painsblue- or white-tinged fingertips or lipsvoice changes

Opacities are also likely to show up on a scan if you have a history of smoking or vaping. It’s also good to know that chest CTs are used to screen for risk of lung cancer, and a physician may order a CT scan if you have a history of smoking. Lung opacities can indicate many conditions besides cancer.

• Many times they are benign (noncancerous).
• They may be due to infections, hemorrhages, a history of smoking, and even COVID-19.
• Lung opacities are common, 2021 research suggests.
• They can indicate a broad range of conditions, and your doctor may need to do further scans and tests to determine the exact cause of any lung opacities.

Lung opacity can show up on the imaging scan in a variety of ways, depending on the underlying condition. Some conditions will result in multiple types of opacities. Opacities may be:

Diffuse: This describes when opacities show up in multiple lobes or both lungs. This is usually the result of fluid, damaged tissue, or inflammation. Nodular: This can mean either a malignant or benign condition. Because this opacity can be caused by small scars from a recent infection, doctors may choose to watch it over several scans to see if it grows. Centrilobular: This type of opacity can appear within one or several lobules of the lung. The connective tissues between the lobules will be unaffected in this type of opacity. Mosaic: Opaque areas vary in intensity in this pattern. It is due to small arteries or airways within the lung being blocked. Crazy paving: This describes a linear pattern that develops when spaces between the lobules widen. Halo sign: This describes when opacity fills the area around the nodules. Reversed halo sign: The opacity will be surrounded by liquid-filled tissue.

Lung opacity can indicate different conditions that have their own treatment plans. Depending on the cause, your doctor may suggest:

steroid medications to reduce inflammation immunosuppressants to prevent your immune system from further damaging your lungs antibiotics oxygen treatments surgery

If the lung opacity is due to cancer, treatment will vary depending on the severity and type. Treatment may include radiation, chemotherapy, and surgery. Lung opacity can result from many different causes, with varying degrees of seriousness. Some conditions that cause lung opacity, like viral infections, are typically short-lived with low long-term risk.

Other conditions, like alveolar hemorrhage and lung cancer, require more serious treatments. Ground-glass opacity nodules can be divided into two types: pure and partially solid. Pure nodules do not contain any solid mass, whereas partially solid nodules do have solid components. A 2019 study found that in cases when lung opacity showed cancer, pure ground-glass opacity nodules were more likely to be seen in earlier stages of lung cancer.

There was also less lymph node invasion compared with ground-glass opacity nodules that also include solid masses. Additionally, pure ground-glass opacity nodules took longer to double in size than ground-glass opacity nodules with solid masses in these studies.

This means that lung cancer outlook may be better when a person has pure ground-glass opacity, compared with scans that showed a solid part in the nodules. After a CT scan or X-ray, a radiologist will look at the scan to determine if there are areas of concern. One thing that can show on a CT scan or X-ray is a degree of haziness referred to as opacity.

Opacity on a lung scan can indicate a concern, but the cause can vary. Your doctor may recommend additional testing to determine the exact cause of any potential lung issues. The outlook and treatment options available will depend on the cause of the opacity.

Can ground glass opacity in lungs be cured?

3. DIAGNOSIS – Lung nodules may be infection, benign nodules, intrapulmonary lymph nodes, or malignant tumors.7 Different types of nodules have different treatment methods, and correct diagnosis is important for clinical treatment. Clinically, low-malignant nodules can be treated with conservative treatment of regular CT follow-up.

If the nodules are increased in size or solid component, more invasive therapy is suggested.11 Infections, benign nodules, and intrapulmonary lymph nodes often resolve or become stationary after regular follow-up. It is recommended to take biopsy for nodules that are clinically suspected of high malignancy or found to increase in size after follow-up.11 Fukui et al.

reported that there was no difference in the pathological stage between patients who had surgery at the beginning and those who had surgery after the tumor size increased.10 For clinical stage IA lung cancer, patients do not need to worry about follow-up leads to tumor progression.12 The current diagnostic methods for pulmonary nodules are mainly divided into the following: (1) Endobronchial ultrasound (EBUS) biopsy, (2) CT-guide biopsy, and (3) surgical excision.

The pooled sensitivity of real-time EBUS in lung cancer is 90% but the false-negative rate is 20%.13 EBUS has a higher diagnosis rate for nodules near the bronchial wall, but a lower diagnosis rate for peripheral type nodule.13 Shimizu reported that the accuracy rate of CT-guide biopsy for small pulmonary nodules is about 64.6%, and it has a higher diagnosis rate (75.6%) for solid-dominant lesions.14 CT-guide biopsy has less discomfort than EBUS biopsy.

However, patients need to receive more radiation exposure, and the diagnosis rate of central type nodules is lower.13, 14 Surgical excision has the highest diagnosis rate, but it is accompanied by the cost of pulmonary function decreasing and longer recovery period.

• It is not recommended to use surgical excision as a diagnostic tool for nodules with low clinical malignancy.
• However, Huang et al.
• Reported that for patients with stage-I lung cancer, preoperative biopsy may increase the risk of tumor recurrence.15 For clinical nodules with high malignancy, direct surgical resection is also a suitable treatment method.

Patients can discuss the malignancy of nodules with clinicians and choose proper treatment strategies such as regular CT follow-up, biopsy, or surgical resection.

What is the survival rate of ground glass opacity?

Introduction – Ground-glass opacity (GGO) is characterized by a radiological finding in high-resolution computed tomography (HRCT) consisting of a hazy opacity that does not obscure the underlying bronchial structures or pulmonary vessels ( 1 ), ranging in diameter from 3mm to 3cm ( 2 ).

1. It is divided into pure ground-glass opacity (pGGO) and mixed ground-glass opacity (mGGO) according to whether it contains solid components.
2. The pGGO refers to the nodule that grows along the alveolar wall, without the destruction of the alveolar structure.
3. As the size of pGGO increases, with alveolar structure collapses, fibroblasts proliferate, and solid components increase, pGGO becomes mGGO ( 2 ).

GGO can be a manifestation of a wide variety of clinical features, including malignancies and benign conditions such as focal interstitial fibrosis, inflammation, and hemorrhage ( 3 ). The classification of lung adenocarcinoma jointly published by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS), which is mainly classified as adenocarcinoma in situ (AIS), micro invasive adenocarcinoma (MIA), invasive adenocarcinoma (IA) and atipical adenomatous hyperplasia (AAH) ( 4 ).

The GGO in young patients has been increasingly encountered in routine clinical practice with the increasingly widespread use of HRCT and the increased resolution of HRCT imaging ( 5 ), which made the diagnosis and treatment of GGO in young patients become a hot spot today. Numerous studies have confirmed that GGO was closely related to early lung adenocarcinoma ( 6 ), GGO has been used as a screening indicator for lung cancer.

The survival rate of surgical resection was close to 100% ( 7, 8 ). Favorable prognoses for the surgical resection of nodules with a considerable amount of GGO have been reported in several retrospective studies ( 9 – 11 ). However, no scholars have reported the clinical characteristics and prognosis of GGO in young patients systematically.

• In addition, It has also not yet been established which surgical procedures including treatment of lymph nodes and surgical methods are well-balanced.
• We collected the clinical data of 127 young patients who have been diagnosed as GGO and treated with video-assisted thoracoscopic surgery (VATS) in the past year for retrospective analysis.

The aim of this study was to clarify its clinical characteristics and prognosis.

What causes ground glass opacity in the lungs?

INTRODUCTION – The tomographic pattern of ground-glass opacities is a non-specific finding, and may reflect interstitial thickening, partial filling or partial collapse of the alveoli, increased blood supply or even a combination of these findings. Radiographically, it is defined as an increase in the lung parenchyma density, but with preservation of the bronchovascular markings, differing from consolidation.

1. 1, 2 ) The causes of ground-glass opacities can be divided into acute and chronic.
2. Among the acute causes are infections (atypical bacterial and viral infections), alveolar hemorrhage, pulmonary edema, diffuse alveolar damage, pulmonary embolism, and some neoplasms.
3. 3 – 9 ) In the context of the pandemic caused by the coronavirus 2 of severe acute respiratory syndrome (SARS-CoV-2), early diagnosis is mandatory to reduce the risk of infection and its spreading.

Despite being a frequent finding in coronavirus 2019 disease (COVID-19), ground-glass opacities are not pathognomonic of coronavirus infection. Therefore, none of the other causes should be neglected in the differential diagnosis. To help determine a suggestive diagnosis from computed tomography (CT) imaging, this finding should be correlated with the other characteristics of the image and the patients’ clinical and laboratory data.

How long does it take for ground glass opacity to grow?

Ground glass nodules with 5 years’ stability can grow after 10-year follow-up: do genetic features determine the fate? Ground-glass nodules (GGNs) in the lung are lesions that appear hazy on computed tomography (CT), without obscuring underlying bronchial structures or pulmonary vessels. Both benign lesions including inflammation, hemorrhage, or focal interstitial fibrosis, and malignancies can present as GGNs. Slow-growing or stable GGNs indicate the presence of early stage lung cancers or preinvasive lesions, such as atypical adenomatous hyperplasia (AAH) and adenocarcinoma in situ (AIS) (); these, along with lepidic predominant lung adenocarcinomas, grow along alveolar structures, maintain the air space and thus appear as GGNs on CT. GGNs are categorized into pure GGNs without solid components and part solid GGNs with solid components. AAH and AIS typically present as pure GGNs, whereas minimally invasive adenocarcinoma (MIA) and lepidic invasive adenocarcinoma are found as part solid GGNs, because their pathologically invasive parts appear solid on CT. High-quality CT images with thin-section slices have been clinically available since the early 2000’s. Between 2008 and 2013, five reports (including ours) have described the natural history of more than 100 GGNs, with median or mean follow-up periods of 2.4 to 4.9 years (-). Although the inclusion criteria and definition of growth in each of these reports vary, the overall data show that 16% of pure GGNs and 41% of part solid GGNs increase their size or solid components, whereas the rest did not change () (). Our paper underscores that the tendency of GGNs to grow is clear in all cases within the first 3 years; thus, we had suggested that a 3-year follow-up is reasonable to distinguish these lesions, considering that the tumor doubling time of GGN is about 800 to 1,000 days (). Natural history of ground glass nodules. The growth rates and median or mean follow-up period are summarized. Heterogenous GGN is defined as GGN with solid components only in the lung window but not in the mediastinal window setting (). GGN, ground-glass nodule. In 2016, data of a prospective study conducted in 8 institutions were reported by Kakinuma et al. (). As many as 1,229 GGNs in 795 patients were evaluated with a mean follow-up period of 4.3 years. The 2-mm growth probability in year 5 was 14%, 24%, and 48% for pure, heterogeneous (part solid GGN in the lung window setting but the solid component disappears in mediastinal window setting) and part-solid GGNs, respectively. Some GGNs did begin to increase their size after 3-year follow-up. In 2017 the minimum period of following GGNs in the updated guidelines from the Fleischner Society was extended from 3 to 5 years (). However, whether GGNs grow any further after the 5-year follow-up was left unclear. Unfortunately, further analyses of this prospective multi-institutional study, with longer follow-ups, were not preplanned in the protocol. And now, a recent paper by Lee et al. reviews the natural history of GGNs with follow-up period of more than 10 years (). They retrospectively evaluated GGNs that were pure or part solid. and ≤3 cm in diameter, without a limitation on the ratio of the solid part. All GGNs were detected incidentally during regular health checkups done between 2003 and 2017. Of 351 GGNs from 242 patients, 41% changed in size within the first 5 years and the remaining 59% were stable. The majority of the stable GGNs were small and pure: 99% were <10 mm in diameter, 76% were <6 mm, and 78% were pure GGNs. During a 136-month follow-up, an additional 13% of the GGNs (27/208) showed evidence of growth after 5 years of being stable (): this is a remarkable number, even for a retrospective study from a single institution, and is similar to growth rates of conventionally reported pure GGNs (10–16%) (). The 5 year-stability factor seems to be highly selective for a small pure GGNs. Collectively, these findings indicate that in clinical practice, we should not stop following GGNs, given the risk of overlooking potential invasive adenocarcinoma. Lee et al. 's report suggests that we should follow GGNs for at least 10 years. To avoid unnecessary CT examinations, an appropriate follow-up interval between imaging sessions should be established. Also, from Kakinuma's prospective study, the data on volume doubling times (VDTs) of resected GGNs show that median VDTs for AIS, MIA, and invasive adenocarcinoma are not statistically different, and are 811, 802, 631 days, respectively (), while the VDTs for the solid component are 100, 223, 106 days, respectively. These indicate that part-solid GGNs should be more closely followed than pure GGNs. Also, that reported growth predictors such as size (>10 mm) and smoking history (or male gender) should be additionally considered (,). What happens to GGNs at 15 years? Lee and coworkers show that the characteristics of GGNs that had a 10-year stability were as follows: 99% of them were <10 mm in diameter, 77% of them were <6 mm, and 79% of them were pure GGNs (). Based on these characteristics, we predict that approximately 10% of GGNs will grow between 10 to 15 years of follow-up—in other words, 90% of them will still be unchanged; and the cumulative growth rate does not seem to reach 100% even over a few decades. We have evaluated and discussed the influence of genetic features on the growth of GGNs (), and hypothesized that EGFR mutant GGNs will grow, whereas some of KRAS or BRAF mutant GGNs will not grow. Not all KRAS mutant AAHs may be homogenous and differences among these tumors may be derived from different cells of origin (). We also suggest that unchanged AAH involves cancer immunoediting, a process whereby the immune system can constrain as well as promote tumor development. Cancer Immunoediting proceeds through 3 phases—elimination, equilibrium and escape ()—wherein tumor immunogenicity is edited, and immunosuppressive mechanisms that enable disease progression are acquired. We hypothesize that unchanged GGNs are in the equilibrium phase. In conclusion, Lee et al. document that even if GGNs are stable for 5 years, 13% of them will grow during at least an additional 5-year follow-up. Thus, we cannot stop following GGNs by CT but must establish an appropriate interval for CT examinations, based on the possibility of growth. Further genetic analyses could clarify the fate of GGNs. Over the next several years, we expect to obtain data on patients with a follow-up period of 15 years and establish the possibility of growth of the GGNs even after 10 years of stability. The authors are grateful to Dr. Sonal Jhaveri, Science Program Director of Postdoc and Graduate Student Affairs Office in Dana-Farber Cancer Institute, for editing a draft of this commentary. Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Provenance: This is an invited article commissioned by the Academic Editor Chenyang Dai, MD, PhD (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China). Conflicts of Interest: The authors have no conflicts of interest to declare.1. Travis WD, Brambilla E, Noguchi M, et al. International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol 2011; 6 :244-85.10.1097/JTO.0b013e318206a221 2. Hiramatsu M, Inagaki T, Matsui Y, et al. Pulmonary ground-glass opacity (GGO) lesions-large size and a history of lung cancer are risk factors for growth. J Thorac Oncol 2008; 3 :1245-50.10.1097/JTO.0b013e318189f526 3. Kobayashi Y, Fukui T, Ito S, et al. How long should small lung lesions of ground-glass opacity be followed? J Thorac Oncol 2013; 8 :309-14.10.1097/JTO.0b013e31827e2435 4. Matsuguma H, Mori K, Nakahara R, et al. Characteristics of subsolid pulmonary nodules showing growth during follow-up with CT scanning. Chest 2013; 143 :436-43.10.1378/chest.11-3306 5. Chang B, Hwang JH, Choi YH, et al. Natural history of pure ground-glass opacity lung nodules detected by low-dose CT scan. Chest 2013; 143 :172-8.10.1378/chest.11-2501 6. Lee SW, Leem CS, Kim TJ, et al. The long-term course of ground-glass opacities detected on thin-section computed tomography. Respir Med 2013; 107 :904-10.10.1016/j.rmed.2013.02.014 7. Kobayashi Y, Mitsudomi T. Management of ground-glass opacities: should all pulmonary lesions with ground-glass opacity be surgically resected? Transl Lung Cancer Res 2013; 2 :354-63.8. Kakinuma R, Noguchi M, Ashizawa K, et al. Natural History of Pulmonary Subsolid Nodules: A Prospective Multicenter Study. J Thorac Oncol 2016; 11 :1012-28.10.1016/j.jtho.2016.04.006 9. MacMahon H, Naidich DP, Goo JM, et al. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017. Radiology 2017; 284 :228-43.10.1148/radiol.2017161659 10. Lee HW, Jin KN, Lee JK, et al. Long-Term Follow-Up of Ground-Glass Nodules After 5 Years of Stability. J Thorac Oncol 2019; 14 :1370-7.10.1016/j.jtho.2019.05.005 11. Kobayashi Y, Sakao Y, Deshpande GA, et al. The association between baseline clinical-radiological characteristics and growth of pulmonary nodules with ground-glass opacity. Lung Cancer 2014; 83 :61-6.10.1016/j.lungcan.2013.10.017 12. Kobayashi Y, Mitsudomi T, Sakao Y, et al. Genetic features of pulmonary adenocarcinoma presenting with ground-glass nodules: the differences between nodules with and without growth. Ann Oncol 2015; 26 :156-61.10.1093/annonc/mdu505 13. Kobayashi Y, Ambrogio C, Mitsudomi T. Ground-glass nodules of the lung in never-smokers and smokers: clinical and genetic insights. Transl Lung Cancer Res 2018; 7 :487-97.10.21037/tlcr.2018.07.04 14. O'Donnell JS, Teng MWL, Smyth MJ. Cancer immunoediting and resistance to T cell-based immunotherapy. Nat Rev Clin Oncol 2019; 16 :151-67.10.1038/s41571-018-0142-8 : Ground glass nodules with 5 years' stability can grow after 10-year follow-up: do genetic features determine the fate?

What percentage of ground-glass opacities are cancerous?

Introducing a classification according to GGO component to nodules, malignancy was detected in 88% of nodules with a GGO component and in 30% of nodules without a GGO component among nodules

Is ground glass opacity a tumor?

Introduction – Lung cancer is a leading cause of death worldwide and imparts a heavy burden on the economies of both more developed and less developed countries. In 2018, 13% of male and female cancer patients were diagnosed with lung cancer for the first time, and the occurrence of lung cancer continues to increase 1,

A previous article by the National Lung Screening Trial reported that computed tomography (CT) screening could decrease the mortality associated with lung cancer and strongly supported the use of low-dose helical CT in clinical screenings 2, Pure ground-glass opacity (GGO) nodules are important indicators of lung cancer on CT.

GGO nodules are defined as hazy areas, which do not block the parenchymal structures, vessels, and airways under the nodules 3, 4, GGO nodules are divided into two categories according to the different solid component percentages: 1) Pure GGO nodules with no solid component within the nodules and 2) Partially solid nodules with both GGO and solid components 4,

GGO nodules are not a specific manifestation of lung cancer and can also indicate other lung pathologies such as hemorrhage, inflammation, and fibrosis 5, Several studies have reported that GGO nodules could be closely related to lung cancer prognoses. Moreover, mixed GGO nodules are considered to be more invasive when compared with pure GGO nodules 6 – 11,

Saji et al. proposed that the only solid nodular components other than whole tumor sizes detected with high-resolution computed tomography were associate with prognoses and malignancies 12, The relationship of GGO nodules with prognoses remains controversial in articles published in the last decade.

1. The association between pure GGO nodules and prognoses has been underreported, and the number of patients with pure GGO nodules in previous retrospective studies was mostly limited.
2. Pure GGO nodules should be given more attention as an important category of GGO nodules.
3. In this article, we performed a retrospective study to clarify whether pure GGO nodules correlated with prognoses in lung cancer patients.

We also analyzed the clinical characteristics of patients with pure GGO nodules to provide information regarding lung cancer diagnoses and treatments for patients in clinical practice.

How long do ground-glass opacities last after COVID?

Conclusion: The majority of patients have altered PFT at three months, even in patients with mild initial disease, with significantly lower function in patients with residual CT lesions. Steroids do not seem to modify functional and radiological recovery. Long-term follow-up is needed.

What medications cause ground-glass opacities?

Usual Interstitial Pneumonia – Cytotoxic chemotherapeutic agents, such as bleomycin and methotrexate, are the most common cause of UIP. Early high-resolution CT scans may show only scattered or diffuse areas of ground-glass opacity. Later, findings of fibrosis (traction bronchiectasis, honeycombing) predominate in a basal distribution.

What is the life expectancy of a ground-glass nodule?

Most patients present with advanced disease and are faced with a dismal prognosis and a life expectancy of less than 1–2 years.

Are lung opacities cancerous?

Yes, a lung nodule can be cancerous.

What does ground-glass mean on a CT scan?

Ground-glass opacity (GGO) is a common finding on high resolution CT, characterised by areas of hazy increased attenuation of the lung with preservation of bronchial and vascular margins ; it is not to be confused with consolidation, in which bronchovascular structures are obscured.

Are ground-glass opacities benign?

Background – Some pulmonary ground-glass nodules (GGNs) are benign and frequently misdiagnosed due to lack of understanding of their CT characteristics. This study aimed to reveal the CT features and corresponding pathological findings of pulmonary benign GGNs to help improve diagnostic accuracy.

Are ground-glass nodules in lungs serious?

Introduction – Ground-glass nodules (GGNs) on computed tomography (CT) are hazy lesions that do not obscure underlying bronchial structures or pulmonary vessels. GGNs are manifestations of both malignant and benign lesions, such as focal interstitial fibrosis, inflammation, or hemorrhage ( 1 ).

1. However, slowly growing or stable GGNs are early lung cancers or their preinvasive lesions, atypical adenomatous hyperplasia (AAH) or adenocarcinoma in situ (AIS).
2. AAH, AIS, and lepidic predominant lung adenocarcinomas grow along preexisting alveolar structures ( 2 ), which maintain the air space.
3. Therefore, these lesions appear as GGNs on CT.

GGNs are classified into pure GGNs and part-solid GGNs that have both ground-glass and solid components ( Figure 1A ). Representative computed tomography images of pure and part-solid GGN and the definition of the consolidation/tumor (C/T) ratio. GGN, ground-glass nodule. We previously reviewed the pathological features and natural history of the GGN ( 3 ). The proportion of solid components of GGNs is closely related to pathological invasive lesions. The longest diameter of consolidation/longest diameter of tumor ratio (C/T ratio) is commonly used to evaluate the proportion of ground-glass components ( Figure 1B ). Empirically, C/T ratio ≤0.5 has been suggested as a benchmark for pathological invasiveness because the incidence of lymph node metastasis in ≤3 cm GGNs with C/T ratio >0.5 ranges from 21% to 26% ( 4 – 6 ). Solid components of GGN on CT often contain pathologically invasive parts when analyzed under a microscope. Typically, AAH and AIS present as pure GGNs on CT, whereas minimally invasive adenocarcinoma (MIA) and lepidic invasive adenocarcinoma present as part-solid GGNs. Some GGNs exhibit gradual growth, but others remain unchanged for years. We collected recent reports analyzing more than 100 GGNs with information on smoking history ( 7 – 15 ) ( Table 1 ). In total, approximately 60% of GGNs are found in never-smokers. Although there is some inconsistency regarding the incidence of smoking status, 8 of 9 articles reported that GGNs are detected more often in never-smokers. Thus, GGN can be regarded as one of the features of lung cancer in never-smokers. In this review, we have updated recent data on GGNs in terms of smoking and genetic alterations to gain insights into the biological features of lung cancer progression and to suggest clinical management strategies for GGNs.

Can ground-glass lung nodules disappear?

A considerable proportion of GGNs disappear spontaneously. An ill-defined border of a GGN may be a sign of spontaneous regression, which suggests an inflammatory nature (1,7). Several characteristics of GGNs may be the sign of future growth and malignancy.

Does ground-glass opacity show up on xray?

Abstract – Introduction: Ground-glass opacity is commonly seen on radiographic imaging tests of patients admitted for COVID-19. The main objective of this study is to determine if the presence of ground-glass opacity on chest X-rays carried out at the Emergency Department correlates with significantly higher mortality.

A secondary objective is to clarify which characteristics are associated with those patients who presented ground-glass opacity. Methods: Data were obtained from our 2020 hospital admission records. Consequently, this is a retrospective cohort study. Our cohort consists of 300 admissions from a group of elderly with a mean age of 81.6.

There were 49.3% women (148/300) and 50.7% men (152/300). Results: The presence of ground-glass opacity on chest X-rays is a risk factor for in-hospital mortality (RR = 1.6), heart failure (RR = 4.3), respiratory failure (RR = 1.5), acute kidney injury (RR = 1.3) and ICU admission (RR = 2.7).

Can asthma cause ground-glass opacities?

3. Discussion – The patient’s clinical presentation was initially worked up to rule out common causes of shortness of breath and chest pain. Entities like asthma exacerbation, pulmonary embolism, and coronary artery disease were ruled out, and concurrent imaging studies revealed a new diagnostic pathway.

The peripheral ground-glass CT findings offer a narrow differential suggestive of chronic eosinophilic pneumonia, organizing pneumonia, vasculitis, and aspiration. This patient did not have an endemic area travel history and lack of gastrointestinal symptom makes diagnosis helminth infection less likely.

The patient did not have extrapulmonary manifestations such us skin rash, joint pain, or uveitis. Lack of serology makes connective tissue disease less likely in this patient. Infectious disease workup was also all negative. Due to history of asthma, eosinophilic disease secondary to asthma or infection was initially suspected based on clinical and radiographic findings.

1. BAL revealed blood consistent with diffuse alveolar hemorrhage.
2. Acute eosinophilic pneumonia, chronic eosinophilic pneumonia, and SES have all been associated with diffuse alveolar hemorrhage,
3. Bilateral ground-glass opacity on chest CT narrows down the differential diagnosis to eosinophilic lung disease, organizing pneumonia, sarcoidosis, and SES,

Peripheral ground-glass opacity was first described by Gaensler and Carrington as a chest X-ray pattern in chronic eosinophilic pneumonia in 1977, In that report, 53 of 81 (65%) cases of chronic eosinophilic pneumonia had peripheral opacities. However, further studies revealed eosinophilic lung diseases to share the same radiographic pattern,

• Therefore, the reverse batwing sign expands the differential to all eosinophilic lung,
• Peripheral consolidation and peripheral ground-glass appearance are both non-specific for eosinophilic lung disease, although one study by Mochimaru reveals peripheral consolidation is found more frequently in chronic eosinophilic pneumonia and peripheral ground-glass opacity is found more frequently in acute eosinophilic pneumonia,

Distribution of opacity and laterality cannot reliably identify or distinguish these two, This patient with asthma had peripheral ground-glass opacities, anchoring our clinical thinking to the diagnosis of acute eosinophilic pneumonia. Elevated IgE level can be present in eosinophilic lung disease but is not diagnostic,

However, this patient did not show eosinophilia on peripheral blood, bronchoalveolar lavage, or tissue biopsy. Though in patients with intermittent steroid use eosinophilia may not be seen, this missing factor led us to question this diagnosis. The history to silicone injections induced us to inquire about this specific exposure.

Interestingly, SES shares many of the same characteristics as eosinophilic pneumonia. Bilateral, peripheral opacities on imaging and diffuse alveolar hemorrhage can be seen in both, Unfortunately, the tissue biopsy did not reveal a definite diagnosis.

Are ground-glass nodules in lungs serious?

Introduction – Ground-glass nodules (GGNs) on computed tomography (CT) are hazy lesions that do not obscure underlying bronchial structures or pulmonary vessels. GGNs are manifestations of both malignant and benign lesions, such as focal interstitial fibrosis, inflammation, or hemorrhage ( 1 ).

However, slowly growing or stable GGNs are early lung cancers or their preinvasive lesions, atypical adenomatous hyperplasia (AAH) or adenocarcinoma in situ (AIS). AAH, AIS, and lepidic predominant lung adenocarcinomas grow along preexisting alveolar structures ( 2 ), which maintain the air space. Therefore, these lesions appear as GGNs on CT.

GGNs are classified into pure GGNs and part-solid GGNs that have both ground-glass and solid components ( Figure 1A ). Representative computed tomography images of pure and part-solid GGN and the definition of the consolidation/tumor (C/T) ratio. GGN, ground-glass nodule. We previously reviewed the pathological features and natural history of the GGN ( 3 ). The proportion of solid components of GGNs is closely related to pathological invasive lesions. The longest diameter of consolidation/longest diameter of tumor ratio (C/T ratio) is commonly used to evaluate the proportion of ground-glass components ( Figure 1B ). Empirically, C/T ratio ≤0.5 has been suggested as a benchmark for pathological invasiveness because the incidence of lymph node metastasis in ≤3 cm GGNs with C/T ratio >0.5 ranges from 21% to 26% ( 4 – 6 ). Solid components of GGN on CT often contain pathologically invasive parts when analyzed under a microscope. Typically, AAH and AIS present as pure GGNs on CT, whereas minimally invasive adenocarcinoma (MIA) and lepidic invasive adenocarcinoma present as part-solid GGNs. Some GGNs exhibit gradual growth, but others remain unchanged for years. We collected recent reports analyzing more than 100 GGNs with information on smoking history ( 7 – 15 ) ( Table 1 ). In total, approximately 60% of GGNs are found in never-smokers. Although there is some inconsistency regarding the incidence of smoking status, 8 of 9 articles reported that GGNs are detected more often in never-smokers. Thus, GGN can be regarded as one of the features of lung cancer in never-smokers. In this review, we have updated recent data on GGNs in terms of smoking and genetic alterations to gain insights into the biological features of lung cancer progression and to suggest clinical management strategies for GGNs.

Can ground-glass lung nodules disappear?

A considerable proportion of GGNs disappear spontaneously. An ill-defined border of a GGN may be a sign of spontaneous regression, which suggests an inflammatory nature (1,7). Several characteristics of GGNs may be the sign of future growth and malignancy.

Is ground glass opacity a tumor?

Introduction – Lung cancer is a leading cause of death worldwide and imparts a heavy burden on the economies of both more developed and less developed countries. In 2018, 13% of male and female cancer patients were diagnosed with lung cancer for the first time, and the occurrence of lung cancer continues to increase 1,

A previous article by the National Lung Screening Trial reported that computed tomography (CT) screening could decrease the mortality associated with lung cancer and strongly supported the use of low-dose helical CT in clinical screenings 2, Pure ground-glass opacity (GGO) nodules are important indicators of lung cancer on CT.

GGO nodules are defined as hazy areas, which do not block the parenchymal structures, vessels, and airways under the nodules 3, 4, GGO nodules are divided into two categories according to the different solid component percentages: 1) Pure GGO nodules with no solid component within the nodules and 2) Partially solid nodules with both GGO and solid components 4,

• GGO nodules are not a specific manifestation of lung cancer and can also indicate other lung pathologies such as hemorrhage, inflammation, and fibrosis 5,
• Several studies have reported that GGO nodules could be closely related to lung cancer prognoses.
• Moreover, mixed GGO nodules are considered to be more invasive when compared with pure GGO nodules 6 – 11,

Saji et al. proposed that the only solid nodular components other than whole tumor sizes detected with high-resolution computed tomography were associate with prognoses and malignancies 12, The relationship of GGO nodules with prognoses remains controversial in articles published in the last decade.

The association between pure GGO nodules and prognoses has been underreported, and the number of patients with pure GGO nodules in previous retrospective studies was mostly limited. Pure GGO nodules should be given more attention as an important category of GGO nodules. In this article, we performed a retrospective study to clarify whether pure GGO nodules correlated with prognoses in lung cancer patients.

We also analyzed the clinical characteristics of patients with pure GGO nodules to provide information regarding lung cancer diagnoses and treatments for patients in clinical practice.

What medications cause ground-glass opacities?

Usual Interstitial Pneumonia – Cytotoxic chemotherapeutic agents, such as bleomycin and methotrexate, are the most common cause of UIP. Early high-resolution CT scans may show only scattered or diffuse areas of ground-glass opacity. Later, findings of fibrosis (traction bronchiectasis, honeycombing) predominate in a basal distribution.