Imaging diagnostics of pulmonary ground-glass nodules: a narrative review with current status and future directions.

Background and Objective: The incidence rate of lung cancer, which also has the highest mortality rates for both men and women worldwide, is increasing globally. Due to advancements in imaging technology and the growing inclination of individuals to undergo screening, the detection rate of ground-glass nodules (GGNs) has surged rapidly. Currently, artificial intelligence (AI) methods for data analysis and interpretation, image processing, illness diagnosis, and lesion prediction offer a novel perspective on the diagnosis of GGNs. This article aimed to examine how to detect malignant lesions as early as possible and improve clinical diagnostic and treatment decisions by identifying benign and malignant lesions using imaging data. It also aimed to describe the use of computed tomography (CT)-guided biopsies and highlight developments in AI techniques in this area. Methods: We used PubMed, Elsevier ScienceDirect, Springer Database, and Google Scholar to search for information relevant to the article's topic. We gathered, examined, and interpreted relevant imaging resources from the Second Affiliated Hospital of Nanchang University's Imaging Center. Additionally, we used Adobe Illustrator 2020 to process all the figures. Key Content and Findings: We examined the common signs of GGNs, elucidated the relationship between these signs and the identification of benign and malignant lesions, and then described the application of AI in image segmentation, automatic classification, and the invasiveness prediction of GGNs over the last three years, including its limitations and outlook. We also discussed the necessity of conducting biopsies of persistent pure GGNs. Conclusions: A variety of imaging features can be combined to improve the diagnosis of benign and malignant GGNs. The use of CT-guided puncture biopsy to clarify the nature of lesions should be considered with caution. The development of new AI tools brings new possibilities and hope to improving the ability of imaging physicians to analyze GGN images and achieving accurate diagnosis.

Predictors of relapse of polymyositis/dermatomyositis associated interstitial lung disease.

Background: Polymyositis/dermatomyositis (PM/DM) patients often develop interstitial lung disease (ILD), which can lead to relapse despite anti-inflammatory treatments. This study aims to elucidate the clinical characteristics of relapses in PM/DM-associated ILD patients. Methods: We gathered clinical data, including laboratory results, pulmonary function tests, chest high-resolution computed tomography findings from patients treated at Okinawa Chubu Hospital between January 1, 2010 and December 31, 2018. Results: We identified a total of 74 patients, comprising 21 men and 53 women. Among them, 38 patients remained relapse-free with maintenance therapy, while 36 experienced relapses despite immunosuppressive management. We followed these patients until June 30, 2023, and 13 patients died. The median survival period was 51.4 months (range, 0.3-214 months). When comparing clinical variables, relapsed patients tended to be younger (49.9 vs. 64.1 years), reported myalgia and rash more frequently (63.9% vs. 28.9% and 61.15% vs. 21.1%, respectively). In terms of laboratory findings, lactate dehydrogenase (LDH) levels were higher in relapsed patients (613±464 vs. 381±203 U/L). Radiological findings showed that ground glass opacity (GGO) was more prevalent in relapsed patients (58.3% vs. 16.7%). A Cox-proportional hazards model for relapse demonstrated that serum LDH [hazard ratio (HR) 1.005, 95% confidence interval (CI): 1.000-1.009, P=0.02] and GGO (HR 1.863, 95% CI: 1.103-3.147, P=0.02) were valuable predictors of relapse. Receiver operating characteristic curve analysis of serum LDH indicated that a threshold of 450 correctly classified relapse in PM/DM-associated ILD patients. Conclusions: Serum LDH and GGO may serve as predictors of relapse in PM/DM-associated ILD patients.

Protocol for a single-arm, multicenter, prospective, confirmatory phase III trial of wedge resection for invasive ground glass opacity-featured lung cancer with a size ≤2 cm and a consolidation tumor ratio between 0.25 and 0.5 (ECTOP-1020 study).

Background: Segmentectomy is the current standard treatment for ground glass opacity (GGO)-featured lung cancer patients with a tumor size ≤2 cm and a consolidation tumor ratio (CTR) between 0.25 and 0.5. However, compared with wedge resection, segmentectomy destroys the patient's hilar structure and consumes more lung parenchyma. A recent study demonstrated that wedge resection could yield comparable results for this group of patients. Methods: This study aimed to confirm the noninferiority of wedge resection over standard surgery in invasive GGO-featured lung cancer patients with a size ≤2 cm and a CTR between 0.25 and 0.5, as measured by 5-year overall survival (OS). The primary endpoint is 5-year OS. The secondary endpoints are 5-year recurrence-free survival (RFS), the R0 resection rate, pulmonary function, recurrence and metastasis sites, and adverse events after surgery. During the trial period, 286 patients are enrolled from six Chinese institutions. Discussion: The primary results of this study will be actively disseminated through manuscript publications and conference presentations. This prospective study will evaluate the surgical efficacy and safety of wedge resection for small (tumor size ≤2 cm with a CTR between 0.25 and 0.5) invasive GGO-featured lung cancer and will support the standardization of this surgical strategy. Trial Registration: This trial has been registered on ClinicalTrial.gov (No. NCT06102161).

Reversed halo sign as a radiological feature of tuberculosis - Report of two cases.

Reversed halo sign (RHS) is a radiological feature described as a focal, rounded area of ground-glass opacity surrounded by a ring of consolidation. In this report we describe two unique radiological cases demonstrating diffuse bilateral infiltrates with multiple RHSs in chest CT scans. Both patients were ultimately diagnosed as having tuberculosis (TB) and had been exposed to silica in the past. This report presents for the first time an association between silica exposure and RHS on CT scans among TB patients. It highlights the importance of having a high index of suspicion for TB in similar scenarios.

Resected lung adenocarcinoma with lymph node metastasis: is ground glass opacity component a prognostic factor?

Background: Ground glass opacity (GGO)-featured lung adenocarcinoma generally has excellent prognosis, and here is rarely the occurrence of lymph node metastasis. We conducted a retrospective cohort study to explore the prognostic impact of GGO component in node-positive lung adenocarcinomas. Methods: A total of 669 patients with pathologic N1/N2 lung adenocarcinoma receiving R0 resection and systemic lymph node dissection from 2008 to 2015 were reviewed, including 635 solid and 34 part-solid lesions. Propensity score matching (PSM) was performed to compare survival outcomes of solid and part-solid lesions, in order to determine the prognostic value of GGO component. Cox proportional hazard model was performed to identify significant prognostic factors for resected node positive lung adenocarcinoma. Results: About 5.1% (34 of 669) of resected node-positive lung adenocarcinoma presented as part-solid nodules on computed tomography (CT) images in this cohort. The median nodule size on CT of the 34 part-solid lesions was 31 mm (range, 15-68 mm), median solid component size on CT was 24 mm (range, 12-62 mm), and median consolidation/tumor ratio was 0.8 (range, 0.64-0.95). After 1:4 PSM, 136 patients and 34 patients were matched from the solid and part-solid groups. No significant difference in either recurrence-free survival (RFS) (P=0.71) or overall survival (OS) (P=0.82) was found between the solid and part-solid groups. Multivariable Cox regression showed that pN stage was the strongest prognostic factor for RFS and OS. GGO component was not an independent prognostic factor toward for RFS [P=0.75; hazard ratio (HR) =0.93; 95% confidence interval (CI): 0.59-1.46] or OS (P=0.53; HR =1.19; 95% CI: 0.69-2.05). Conclusions: A minority of resected node-positive lung adenocarcinoma presents as GGO component on CT. The presence of GGO component does not predict better prognosis in node-positive lung adenocarcinoma.

Segmentectomy versus lobectomy for ground-glass opacity dominant cT1N0 invasive lung adenocarcinoma.

Background: The Japan Clinical Oncology Group (JCOG) 1211 suggested that segmentectomy should be considered as standard treatment for clinical T1N0 (cT1N0) ground glass opacity (GGO). However, over half of patients in JCOG1211 had pre-/minimal invasive adenocarcinoma. This study aims to retrospectively investigate the long-term survival of GGO featured cT1N0 invasive lung adenocarcinoma undergoing segmentectomy or lobectomy. Methods: This study screened patients with primary cT1N0 lung adenocarcinoma who received segmentectomy or lobectomy from 2010-2020. Prior computed tomography (CT) scans before surgery of all patients were reviewed and the inclusion was confirmed according to tumor diameter and consolidation tumor ratio (CTR). GGO nodules between 2-3 cm with CTR ≤0.5 or ≤2 cm with CTR between 0.25-0.5 were finally included. Patients with pathologically diagnosed pre-/minimally invasive lung adenocarcinoma were excluded. Long-term survivals between segmentectomy group and lobectomy group were compared after propensity score matching (PSM). Recurrence and postoperative complication events were also analyzed. Results: In total, 617 patients were enrolled, 159 received segmentectomy and 458 received lobectomy. Clinicopathological characteristics were well distributed between two groups. With a median follow-up time of 61.1 months (IQR: 42.3-71.7 months), after PSM, the 5-year overall survival rate was 98.8% (97.9-99.6%) for lobectomy and 99.3% (98.2-99.8%) for segmentectomy (P=0.42), the 5-year relapse-free survival rate was 95.3% (92.2-97.6%) for lobectomy and 95.2% for segmentectomy (92.3-98.7%) (P=0.81). The proportion of recurrence was 4.1% for lobectomy and 4.4% for segmentectomy (P=0.89). The proportion of grade 2 and above early postoperative complications was 9.6% for lobectomy and 8.8% for segmentectomy (P=0.86). Conclusions: For cT1N0 GGO featured invasive lung adenocarcinoma (2 cm < tumor diameter ≤3 cm, CTR ≤0.5 or tumor diameter ≤2 cm, 0.25< CTR ≤0.5), postoperative outcomes between segmentectomy group and lobectomy group were comparable. Concerning minimally invasive surgical strategy, segmentectomy should be confirmed as the standard surgical approach.

Different clinicopathological features between young and older patients with pulmonary adenocarcinoma and ground-glass opacity.

After the recommendation of computed tomography as a routine procedure for lung cancer screening, an increasing number of young adults have been diagnosed with pulmonary ground-glass opacity (GGO). Up to 63% of pulmonary nodules with a GGO component can be malignant. Since young cancer patients have limited exposure to environmental mutagens, they have special characteristics and needs. This study sought to compare the clinicopathological characteristics of young and old patients with GGO-associated lung adenocarcinoma (GGO-LUAD). Clinicopathological data from 203 patients who underwent video-assisted thoracoscopic surgery between January 2018 and April 2020 for pulmonary GGO component nodules were reviewed. Lung nonmucinous adenocarcinoma patients younger than 40 years old and older than 40 years old were enrolled: 103 patients ≤ 40 years old and 100 patients > 40 years old. The relevant clinicopathological features, including sex, smoking status, tumor size, pathological characteristics, radiographic features and prognosis of pulmonary nodules, were evaluated. Univariate analyses were applied for comparisons between groups. The differences in baseline characteristics (sex, smoking status, tumor location) between the different age groups were not significant. Young patients were more likely to have tumors < 1 cm in size, while older patients predominantly had tumors > 2 cm in size. The mean percentage of invasive adenocarcinoma was greater in the elderly group. Young and older patients seemed to have similar subtypes of adenocarcinoma (p > 0.05) but had different degrees of differentiation (p < 0.001). The 3-year overall survival (OS) and recurrence-free survival (RFS) of the young group were 100% and 99.03%, respectively, while the 3-years OS and RFS of the older group were 99% and 98%, respectively. Our work revealed that young patients with malignant pulmonary nodules and GGOs have distinct pathological subtypes. Patients with GGOs of different ages have different clinicopathological characteristics. The 3-year prognosis of young patients with malignant pulmonary nodules with GGOs is satisfactory.

Diagnostic accuracy of low-dose dual-input computed tomography perfusion in the differential diagnosis of pulmonary benign and malignant ground-glass nodules.

This study aimed to evaluate the value of low-dose dual-input computed tomography perfusion (CTP) imaging in the differential diagnosis of benign and malignant pulmonary ground-glass opacity nodules (GGO). A retrospective study was conducted in patients with GGO who underwent CTP in our hospital from January 2021 to October 2023. All nodules were confirmed via pathological analysis or disappeared during follow-up. Postprocessing analysis was conducted using the dual-input perfusion mode (pulmonary artery and bronchial artery) of the body perfusion software to measure the perfusion parameters of the pulmonary GGOs. A total of 101 patients with pulmonary GGOs were enrolled in this study, including 43 benign and 58 malignant nodules. The dose length product of the CTP (348 mGy.cm) was < 75% of the diagnostic reference level of the unenhanced chest CT (470 mGy.cm). The effective radiation dose was 4.872 mSV. The blood flow (BF), blood volume (BV), mean transit time (MTT), and flow extraction product (FEP) of malignant nodules were higher than those of the benign nodules (p < 0.05). The FEP had the highest accuracy for the diagnosis of malignant nodules (area under the curve [AUC] = 0.821, 95% confidence interval [CI]: 0.735-0.908) followed by BV (AUV = 0.713, 95% CI 0.608-0.819), BF (AUC = 0.688, 95% CI 0.587-0.797), and MTT (AUC = 0.616, 95% CI 0.506-0.726). When the FEP was ≥ 19.12 mL/100 mL/min, the sensitivity was 91.5% and the specificity was 62.8%. To distinguish between benign nodules and malignant nodules, the AUC of the combination of BV and FEP was 0.816 (95% CI 0.728-0.903), whereas the AUC of the combination of BF, BV, MTT, and FEP was 0.814 (95% CI 0.729-0.900). Low-dose dual-input perfusion CT was extremely effective in distinguishing between benign from malignant pulmonary GGOs, with FEP exhibiting the highest diagnostic capability.

A case of lung metastasis from gastric cancer presenting as ground-glass opacity dominant nodules.

BACKGROUND: Most metastatic lung tumors present as solid nodules on chest computed tomography (CT). In contrast, ground-glass opacity on chest computed tomography usually suggests low-grade malignant lesions such as adenocarcinoma in situ or atypical adenomatous hyperplasia of the lung. CASE PRESENTATION: A 75-year-old woman with a history of gastric cancer surgery approximately 5 years prior was referred to the Department of Thoracic Surgery at our hospital because of two newly appearing pulmonary ground-glass opacity-dominant nodules on chest computed tomography. She had two ground-glass opacities in the right lower lobe, one in the S6 segment was 12 mm and the other in the S10 segment was 8 mm. On chest computed tomography 15 months prior to referral, the lesion in the S6 segment was 8 mm, and the lesion in the S10 segment was 2 mm. She was suspected to have primary lung cancer and underwent wide-wedge resection of the nodule in the S6 segment. In the resected specimen, polygonal tumor cells infiltrated the alveolar septa, with some tumor cells exhibiting signet ring cell morphology. Based on morphological similarities to the tumor cells of previous gastric cancers and the results of immunostaining, the patient was diagnosed with lung metastases of gastric cancer. CONCLUSIONS: Pulmonary nodules in patients with a history of cancer in other organs, even if ground-glass opacity is predominant, should also be considered for the possibility of metastatic pulmonary tumors if they are growing rapidly.

Association of Ground Glass Opacities with Systemic Inflammation and Progression of Emphysema.

RATIONAL: Ground glass opacities (GGO) in the absence of interstitial lung disease are understudied. OBJECTIVE: To assess the association of GGO with white blood cells (WBCs) and progression of quantified chest CT emphysema. METHODS: We analyzed data of participants in the Subpopulations and Intermediate Outcome Measures In COPD Study (SPIROMICS). Chest radiologists and pulmonologists labeled regions of the lung as GGO and adaptive multiple feature method (AMFM) trained the computer to assign those labels to image voxels and quantify the volume of the lung with GGO (%GGOAMFM). We used multivariable linear regression, zero-inflated negative binomial, and proportional hazards regression models to assess the association of %GGOAMFM with WBC, changes in %emphysema, and clinical outcomes. MEASUREMENTS AND MAIN RESULTS: Among 2,714 participants, 1,680 had COPD and 1,034 had normal spirometry. Among COPD participants, based on the multivariable analysis, current smoking and chronic productive cough was associated with higher %GGOAMFM. Higher %GGOAMFM was cross-sectionally associated with higher WBCs and neutrophils levels. Higher %GGOAMFM per interquartile range at visit 1 (baseline) was associated with an increase in emphysema at one-year follow visit by 11.7% (Relative increase; 95%CI 7.5-16.1%;P<0.001). We found no association between %GGOAMFM and one-year FEV1 decline but %GGOAMFM was associated with exacerbations and all-cause mortality during a median follow-up time of 1,544 days (Interquartile Interval=1,118-2,059). Among normal spirometry participants, we found similar results except that %GGOAMFM was associated with progression to COPD at one-year follow-up. CONCLUSIONS: Our findings suggest that GGOAMFM is associated with increased systemic inflammation and emphysema progression.

The 2023 American Association for Thoracic Surgery (AATS) Expert Consensus Document: Management of subsolid lung nodules.

OBJECTIVE: Lung cancers that present as radiographic subsolid nodules represent a subtype with distinct biological behavior and outcomes. The objective of this document is to review the existing literature and report consensus among a group of multidisciplinary experts, providing specific recommendations for the clinical management of subsolid nodules. METHODS: The American Association for Thoracic Surgery Clinical Practice Standards Committee assembled an international, multidisciplinary expert panel composed of radiologists, pulmonologists, and thoracic surgeons with established expertise in the management of subsolid nodules. A focused literature review was performed with the assistance of a medical librarian. Expert consensus statements were developed with class of recommendation and level of evidence for each of 4 main topics: (1) definitions of subsolid nodules (radiology and pathology), (2) surveillance and diagnosis, (3) surgical interventions, and (4) management of multiple subsolid nodules. Using a modified Delphi method, the statements were evaluated and refined by the entire panel. RESULTS: Consensus was reached on 17 recommendations. These consensus statements reflect updated insights on subsolid nodule management based on the latest literature and current clinical experience, focusing on the correlation between radiologic findings and pathological classifications, individualized subsolid nodule surveillance and surgical strategies, and multimodality therapies for multiple subsolid lung nodules. CONCLUSIONS: Despite the complex nature of the decision-making process in the management of subsolid nodules, consensus on several key recommendations was achieved by this American Association for Thoracic Surgery expert panel. These recommendations, based on evidence and a modified Delphi method, provide guidance for thoracic surgeons and other medical professionals who care for patients with subsolid nodules.

Recent Advancements in Minimally Invasive Surgery for Early Stage Non-Small Cell Lung Cancer: A Narrative Review.

Introduction: Lung cancer remains a global health concern, with non-small cell lung cancer (NSCLC) comprising the majority of cases. Early detection of lung cancer has led to an increased number of cases identified in the earlier stages of NSCLC. This required the revaluation of the NSCLC treatment approaches for early stage NSCLC. Methods: We conducted a comprehensive search using multiple databases to identify relevant studies on treatment modalities for early stage NSCLC. Inclusion criteria prioritized, but were not limited to, clinical trials and meta-analyses on surgical approaches to early stage NSCLC conducted from 2021 onwards. Discussion: Minimally invasive approaches, such as VATS and RATS, along with lung resection techniques, including sublobar resection, have emerged as treatments for early stage NSCLC. Ground-glass opacities (GGOs) have shown prognostic significance, especially when analyzing the consolidation/tumor ratio (CTR). There have also been updates on managing GGOs, including the non-surgical approaches, the extent of lung resection indicated, and the level of lymphadenectomy required. Conclusions: The management of early stage NSCLC requires a further assessment of treatment strategies. This includes understanding the required extent of surgical resection, interpreting the significance of GGOs (specifically GGOs with a high CTR), and evaluating the efficacy of alternative therapies. Customized treatment involving surgical and non-surgical interventions is essential for advancing patient care.

Clinical characteristics, radiological features and outcomes in pulmonary involvement of cryoglobulinemia.

BACKGROUND: Cryoglobulinemia with pulmonary involvement is rare, and its characteristics, radiological findings, and outcomes are still poorly understood. METHODS: Ten patients with pulmonary involvement of 491 cryoglobulinemia patients at Peking Union Medical College Hospital were enrolled in this retrospective study. We analyzed the characteristics, radiological features and management of pulmonary involvement patients, and compared with those of non-pulmonary involvement with cryoglobulinemia. RESULTS: The 10 patients with pulmonary involvement (2 males; median age, 53 years) included three patients with type I cryoglobulinemia and seven patients with mixed cryoglobulinemia. All of 10 patients were IgM isotype cryoglobulinemia. All type I patients were secondary to B-cell non-Hodgkin lymphoma. Four mixed patients were essential, and the remaining patients were secondary to infections (n = 2) and systemic lupus erythematosus (n = 1), respectively. Six patients had additional affected organs, including skin (60%), kidney (50%), peripheral nerves (30%), joints (20%), and heart (20%). The pulmonary symptoms included dyspnea (50%), dry cough (30%), chest tightness (30%), and hemoptysis (10%). Chest computed tomography (CT) showed diffuse ground-glass opacity (80%), nodules (40%), pleural effusions (30%), and reticulation (20%). Two patients experienced life-threatening diffuse alveolar hemorrhage. Five patients received corticosteroid-based regimens, and four received rituximab-based regimens. All patients on rituximab-based regimens achieved clinical remission. The estimated two-year overall survival (OS) was 40%. Patients with pulmonary involvement had significantly worse OS and progression-free survival than non-pulmonary involvement patients of cryoglobulinemia (P < 0.0001). CONCLUSIONS: A diagnosis of pulmonary involvement should be highly suspected for patients with cryoglobulinemia and chest CT-indicated infiltrates without other explanations. Patients with pulmonary involvement had a poor prognosis. Rituximab-based treatment may improve the outcome.

Pulmonary Manifestation of Granulomatosis With Polyangiitis: A Challenging Case Presentation.

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is a rare and potentially life-threatening autoimmune disease characterized by antineutrophil cytoplasmic antibody (ANCA)-associated vasculature inflammation. It presents as a systemic autoimmune disease with necrotizing granulomatous inflammation and pauci-immune small vessel vasculitis. This case initially posed a diagnostic challenge due to its atypical presentation and was misdiagnosed as hypersensitivity pneumonitis. The avian precipitin screening assay was positive in our patient, which may be consistent with bird breeder's lung disease or a non-specific reactivity of the chicken antigen test. However, the presence of positive c-ANCA was pivotal for the GPA diagnosis. Here, we describe in detail the clinical manifestations, diagnostic approach, and treatment of GPA in a 54-year-old female who presented with alveolar hemorrhage, but no renal involvement. Treatment involved the use of high-dose corticosteroids to suppress the autoimmune response. Finally, we discuss the striking response of this unique form of granulomatosis with polyangiitis to corticosteroid treatment and emphasize the importance of early initiation of treatment.

Classification of multiple primary lung cancer in patients with multifocal lung cancer: assessment of a machine learning approach using multidimensional genomic data.

Background: Multiple primary lung cancer (MPLC) is an increasingly well-known clinical phenomenon. However, its molecular characterizations are poorly understood, and still lacks of effective method to distinguish it from intrapulmonary metastasis (IM). Herein, we propose an identification model based on molecular multidimensional analysis in order to accurately optimize treatment. Methods: A total of 112 Chinese lung cancers harboring at least two tumors (n = 270) were enrolled. We retrospectively selected 74 patients with 121 tumor pairs and randomly divided the tumor pairs into a training cohort and a test cohort in a 7:3 ratio. A novel model was established in training cohort, optimized for MPLC identification using comprehensive genomic profiling analyzed by a broad panel with 808 cancer-related genes, and evaluated in the test cohort and a prospective validation cohort of 38 patients with 112 tumors. Results: We found differences in molecular characterizations between the two diseases and rigorously selected the characterizations to build an identification model. We evaluated the performance of the classifier using the test cohort data and observed an 89.5% percent agreement (PA) for MPLC and a 100.0% percent agreement for IM. The model showed an excellent area under the curve (AUC) of 0.947 and a 91.3% overall accuracy. Similarly, the assay achieved a considerable performance in the independent validation set with an AUC of 0.938 and an MPLC predictive value of 100%. More importantly, the MPLC predictive value of the classification achieved 100% in both the test set and validation cohort. Compared to our previous mutation-based method, the classifier showed better κ consistencies with clinical classification among all 112 patients (0.84 vs. 0.65, p <.01). Conclusion: These data provide novel evidence of MPLC-specific genomic characteristics and demonstrate that our one-step molecular classifier can accurately classify multifocal lung tumors as MPLC or IM, which suggested that broad panel NGS may be a useful tool for assisting with differential diagnoses.

Primary lung cancer in children and adolescents.

PURPOSE: Primary lung cancer is extremely rare in children and adolescents. The aim of this study is to clarify clinical features and outcomes of primary lung cancer in children and adolescents. METHODS: Young patients (aged ≤ 20 years) diagnosed as primary lung cancer between 2012 and 2023 were retrospective reviewed. According to radiological appearance of the nodules, they were divided into solid nodule (SN) group and ground glass opacity (GGO) group. RESULTS: A total of 74 patients were identified, with a median age at diagnosis of 18 years old (range: 11-20), including 7 patients in SN group and 67 patients in GGO group. In the GGO group, none of the nodules enlarged or changed during an average surveillance period of 10.8 months before surgery, except one. Wedge resection was the most common procedure (82.1%), followed by segmentectomy (16.4%) and lobectomy (1.5%). Histopathological analysis revealed that 64.2% of GGO nodules were adenocarcinoma in situ and minimally invasive adenocarcinomas, while the remaining 35.8% were invasive adenocarcinomas. Mutational analysis was performed in nine patients, with mutations identified in all cases. After a mean follow-up period of 1.73 ± 1.62 years, two patients in the SN group died due to multiple distant metastases, while all patients in the GGO group survived without recurrence. The overall survival (100%) of the GGO group was significantly higher than SN group (66.7%). CONCLUSIONS: Primary lung cancer in children and adolescents are rare and histopathological heterogeneous. Persistent GGO nodules may indicate early-stage lung adenocarcinoma in children and adolescents.

A Case of Immunomodulator-Responsive Hypersensitivity Pneumonitis Secondary to Chronic Passive Smoke Inhalation.

Hypersensitivity pneumonitis (HP) is a pulmonary disease characterized by inflammation and fibrosis of the lung parenchyma following chronic exposure to immunogenic antigens. The pathophysiology of HP involves type 3 and type 4 hypersensitivity reactions leading to acute and chronic manifestations, respectively. Clinically, it manifests as exertional dyspnea and wheezing. Pulmonary function tests display a pattern of restrictive lung disease, and high-resolution CT scans display a pattern of ground glass opacities, centrilobular nodules, and mosaic attenuation. Antigen avoidance remains the only method for primary prevention. Alternative therapy may be needed due to either the inability to avoid antigens or the lack of antigen identification. Prednisone 0.5 mg/kg per day is the first-line treatment for acute non-fibrotic forms of HP. In chronic or fibrotic HP, the immunomodulator mycophenolate mofetil (MMF) was shown to be an effective treatment in improving the diffusing capacity of the lungs for carbon monoxide and forced vital capacity, but not overall survival. The following study aims to bring to attention the need for additional prospective multicenter clinical trials to clarify the role of MMF as an immunomodulator in fibrosing HP.

Minor (≤ 10%) Ground-Glass Opacity Component in Clinical Stage I Non-Small Cell Lung Cancer: Associations With Pathologic Characteristics and Clinical Outcomes.

BACKGROUND. The presence of a ground-glass opacity (GGO) component is a favorable prognostic factor in non-small cell lung cancer (NSCLC), although the prognostic impact of a very small GGO component remains poorly investigated. OBJECTIVE. The purpose of this article is to investigate the impact of a minor (≤ 10%) GGO component on the prognosis of clinical stage I NSCLC in comparison with pure-solid nodules. METHODS. This retrospective study included 382 patients (mean age, 60.8 years; 210 men, 172 women) who underwent surgical resection between January 1, 2015, and December 31, 2015, for clinical stage I NSCLC appearing on preoperative chest CT as a nodule with a consolidation-to-tumor ratio (CTR) of 0.9 to 1.0. Two radiologists independently assigned nodules to groups as either minor GGO (CTR, ≥ 0.9 and < 1.0) or pure solid (CTR = 1.0). Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed by Kaplan-Meier curves and compared between groups using log-rank tests. Cox proportional hazards models were used to assess associations with outcomes. RESULTS. The two radiologists agreed for all nodules' classification into the minor-GGO (n = 106) or pure-solid (n = 276) groups. The mean CTR of the minor-GGO group was 0.93 ± 0.02 (SD) (range, 0.90-0.97). Minor-GGO nodules, in comparison with pure-solid nodules, showed greater solid-component diameter (2.68 vs 2.16 cm; p < .001) and total nodule diameter (2.89 vs 2.16 cm; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed lower frequencies of visceral pleural invasion (6.6% vs 17.0%, p = .009) and pathologic lymph node involvement (4.7% vs 20.3%, p < .001), and EGFR mutation (71.6% vs 39.9%; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed better 5-year RFS (83.4% vs 55.0%; p < .001) and higher frequency of better 5-year CSS (92.4% vs 76.4%, p = .004). In multivariable analysis adjusting for patient, imaging, pathologic, and genetic factors, a minor-GGO component was independently associated with a decreased likelihood of recurrence (HR = 0.37, p = .001) but not with the likelihood of CSS. CONCLUSION. Among patients with clinical stage I NSCLC, cancers with a minor-GGO component were associated with a better prognosis versus those with a pure-solid appearance. CLINICAL IMPACT. Radiologists encountering predominantly solid nodules on CT should carefully assess images for even a minor-GGO component given the favorable prognosis.