Objective:To investigate the clinical pathological features, immunophenotypes, diagnosis, and differential diagnosis of non-small cell lung carcinoma (NSCLC) with trophoblastic differentiation in males, and to improve the understanding of this rare disease.Methods:The clinical and pathological features of 16 NSCLC with trophoblastic differentiation in males diagnosed in Shanghai Pulmonary Hospital from January 2017 to December 2023 were retrospectively analyzed. Relevant literature was reviewed.Results:All 16 patients were male, with an onset median age of 66.5 (56.8, 68.8) years. They had no known personal history of cancer. Among the 8 resected NSCLC with trophoblastic differentiation, 3 showed concurrent lung adenocarcinoma, and 1 showed concurrent lung squamous cell carcinoma. Among the 10 patients who underwent serum β human chorionic gonadotropin (β-HCG) testing after the surgery or biopsy, 7 had significantly increased β-HCG. On gross examination, the tumors were hemorrhagic and necrotic, resembling a hematoma, with a medium texture, clear boundaries and no capsules. At low magnification, tumor cells were arranged in a nested or solid pattern. Those cells often showed massive bleeding, necrosis, and vascular infiltration. They were composed of two types of cells, namely cytotrophoblast and syncytiotrophoblast cells. At high magnification, the tumor cells showed large nuclei and hyperchromatia. They also had rich purple blue to bichromatic cytoplasm, eosinophilic nucleoli, and sometimes bizarre nuclei. The syncytiotrophoblast cells expressed β-HCG, CKpan, GATA3, CD10, and SALL4. Fourteen patients were followed up for 1-37 months. Two of them died, while three showed distant metastasis.Conclusions:NSCLC with trophoblastic differentiation in males is a rare and highly malignant tumor, poorly understood with difficulty in diagnosis. It requires comprehensive histological analysis in combination with clinical and imaging studies. Properly diagnosing this disease relies on recognition of its histopathological characteristics, including large areas of bleeding and necrosis, large and peculiar syncytial trophoblast cells, and varying degrees of β-HCG expression. It seems that β-HCG expression is very valuable for diagnosing this rare tumor.

Purpose To investigate the diagnostic value of immunohistochemical(IHC)and molecular markers in diffuse pleural mesothelioma(DPM).Methods A total of 114 cases of DPM were retrospectively analyzed for clinical and imaging manifestations,histologic subtype and tumor grade.The positivity rates of Calretinin,WT-1,CK5/6,MC,D2-40,UPK3B,and GATA3 were assessed by IHC,and the loss rates of BAP-1 and MTAP were determined.The concordance between MTAP IHC and p16 gene fluorescence in situ hybridization(FISH)status was calculated,a-long with the sensitivity and specificity of MTAP IHC relative to p16 FISH.Results Among the 114 DPM patients,66(57.9％)were male and 48(42.1％)were female,with a mean age of 58.1 years(range 16-85 years).Imaging predominantly demonstrated pleural effusion and multiple pleural nodules(55.3％,63/114).Histologically,epitheli-oid,sarcomatoid and biphasic subtypes accounted for 88(77.2％),17(14.9％)and 9(7.9％)cases,respectively.Within the epithelioid group,low and high-grade tumors numbered 69(78.4％)and 19(21.6％),respectively.In epithelioid DPM,the highest IHC positivity rates were observed for Calretinin(92.4％,81/88),D2-40(90.0％,79/88)and WT-1(90.0％,79/88).In sarcomatoid DPM,D2-40(76.5％,13/17),WT-1(64.7％,11/17),and Cal-retinin(29.4％,5/17)showed the greatest positivity.UPK3B was positive in epithelioid(59.1％,39/66)and bi-phasic cases(66.7％,4/6),but was absent in sarcomatoid tumors(0/12).Among all DPM cases,loss rates were 47.3％(53/112)for BAP-1 and 19.2％(20/104)for MTAP by IHC,p16 gene deletion by FISH was 31.5％(34/108);Concordance between MTAP IHC and p16 FISH was 81.0％(81/100);MTAP IHC had a specificity of 95.5％(64/67)and sensitivity of 51.5％(17/33)relative to p16 FISH.Additionally,GATA3 was highly expressed in sarco-matoid DPM(76.5％,13/17).UPK3B positivity differed significantly between thoracoscopic DPM(59.2％,32/54)and percutaneous biopsy samples(36.7％,11/30)in epithelioid DPM(P＜0.05).WT-1 positivity was higher in thoracoscopic than percutaneous samples of sarcomatoid DPM(90.0％ vs 28.6％,P=0.009).Conclusion Calreti-nin,D2-40,and WT-1 are highly sensitive mesothelial markers and should serve as first-line IHC stains in DPM diag-nosis.UPK3B is diagnostically valuable in epithelioid DPM,GATA3 may complement the diagnosis of sarcomatoid DPM,and MTAP IHC can be used as a surrogate or adjunct to p16 FISH.

The pathological diagnosis of interstitial lung disease (ILD) is challenging, especially with the increasing application and popularization of small biopsy techniques, particularly transbronchial cryobiopsy. As a result, the clinical demand for pathologists to handle small biopsy specimens of ILD in daily practice has been growing. Given the small size of these biopsy specimens and the insufficient diagnostic experience of pathologists in this area, the current pathological diagnosis is struggling to meet clinical needs. Based on our hospital′s practical experience in diagnosing ILD from small biopsies, this article summarizes the key steps from initial learning actual to diagnostic procedures, aiming to lower the diagnostic threshold and improve the confirmation rate.

The pathological diagnosis of interstitial lung disease (ILD) is challenging, especially with the increasing application and popularization of small biopsy techniques, particularly transbronchial cryobiopsy. As a result, the clinical demand for pathologists to handle small biopsy specimens of ILD in daily practice has been growing. Given the small size of these biopsy specimens and the insufficient diagnostic experience of pathologists in this area, the current pathological diagnosis is struggling to meet clinical needs. Based on our hospital′s practical experience in diagnosing ILD from small biopsies, this article summarizes the key steps from initial learning actual to diagnostic procedures, aiming to lower the diagnostic threshold and improve the confirmation rate.

Purpose To investigate the diagnostic value of immunohistochemical(IHC)and molecular markers in diffuse pleural mesothelioma(DPM).Methods A total of 114 cases of DPM were retrospectively analyzed for clinical and imaging manifestations,histologic subtype and tumor grade.The positivity rates of Calretinin,WT-1,CK5/6,MC,D2-40,UPK3B,and GATA3 were assessed by IHC,and the loss rates of BAP-1 and MTAP were determined.The concordance between MTAP IHC and p16 gene fluorescence in situ hybridization(FISH)status was calculated,a-long with the sensitivity and specificity of MTAP IHC relative to p16 FISH.Results Among the 114 DPM patients,66(57.9％)were male and 48(42.1％)were female,with a mean age of 58.1 years(range 16-85 years).Imaging predominantly demonstrated pleural effusion and multiple pleural nodules(55.3％,63/114).Histologically,epitheli-oid,sarcomatoid and biphasic subtypes accounted for 88(77.2％),17(14.9％)and 9(7.9％)cases,respectively.Within the epithelioid group,low and high-grade tumors numbered 69(78.4％)and 19(21.6％),respectively.In epithelioid DPM,the highest IHC positivity rates were observed for Calretinin(92.4％,81/88),D2-40(90.0％,79/88)and WT-1(90.0％,79/88).In sarcomatoid DPM,D2-40(76.5％,13/17),WT-1(64.7％,11/17),and Cal-retinin(29.4％,5/17)showed the greatest positivity.UPK3B was positive in epithelioid(59.1％,39/66)and bi-phasic cases(66.7％,4/6),but was absent in sarcomatoid tumors(0/12).Among all DPM cases,loss rates were 47.3％(53/112)for BAP-1 and 19.2％(20/104)for MTAP by IHC,p16 gene deletion by FISH was 31.5％(34/108);Concordance between MTAP IHC and p16 FISH was 81.0％(81/100);MTAP IHC had a specificity of 95.5％(64/67)and sensitivity of 51.5％(17/33)relative to p16 FISH.Additionally,GATA3 was highly expressed in sarco-matoid DPM(76.5％,13/17).UPK3B positivity differed significantly between thoracoscopic DPM(59.2％,32/54)and percutaneous biopsy samples(36.7％,11/30)in epithelioid DPM(P＜0.05).WT-1 positivity was higher in thoracoscopic than percutaneous samples of sarcomatoid DPM(90.0％ vs 28.6％,P=0.009).Conclusion Calreti-nin,D2-40,and WT-1 are highly sensitive mesothelial markers and should serve as first-line IHC stains in DPM diag-nosis.UPK3B is diagnostically valuable in epithelioid DPM,GATA3 may complement the diagnosis of sarcomatoid DPM,and MTAP IHC can be used as a surrogate or adjunct to p16 FISH.

Objective:To investigate the clinical pathological features, immunophenotypes, diagnosis, and differential diagnosis of non-small cell lung carcinoma (NSCLC) with trophoblastic differentiation in males, and to improve the understanding of this rare disease.Methods:The clinical and pathological features of 16 NSCLC with trophoblastic differentiation in males diagnosed in Shanghai Pulmonary Hospital from January 2017 to December 2023 were retrospectively analyzed. Relevant literature was reviewed.Results:All 16 patients were male, with an onset median age of 66.5 (56.8, 68.8) years. They had no known personal history of cancer. Among the 8 resected NSCLC with trophoblastic differentiation, 3 showed concurrent lung adenocarcinoma, and 1 showed concurrent lung squamous cell carcinoma. Among the 10 patients who underwent serum β human chorionic gonadotropin (β-HCG) testing after the surgery or biopsy, 7 had significantly increased β-HCG. On gross examination, the tumors were hemorrhagic and necrotic, resembling a hematoma, with a medium texture, clear boundaries and no capsules. At low magnification, tumor cells were arranged in a nested or solid pattern. Those cells often showed massive bleeding, necrosis, and vascular infiltration. They were composed of two types of cells, namely cytotrophoblast and syncytiotrophoblast cells. At high magnification, the tumor cells showed large nuclei and hyperchromatia. They also had rich purple blue to bichromatic cytoplasm, eosinophilic nucleoli, and sometimes bizarre nuclei. The syncytiotrophoblast cells expressed β-HCG, CKpan, GATA3, CD10, and SALL4. Fourteen patients were followed up for 1-37 months. Two of them died, while three showed distant metastasis.Conclusions:NSCLC with trophoblastic differentiation in males is a rare and highly malignant tumor, poorly understood with difficulty in diagnosis. It requires comprehensive histological analysis in combination with clinical and imaging studies. Properly diagnosing this disease relies on recognition of its histopathological characteristics, including large areas of bleeding and necrosis, large and peculiar syncytial trophoblast cells, and varying degrees of β-HCG expression. It seems that β-HCG expression is very valuable for diagnosing this rare tumor.

Objective:To investigate the clinicopathological features and genetic characteristics of congenital cystic adenomatoid malformation (CCAM) of lung and CCAM associated lung cancer in adults.Methods:A total of 13 cases of CCAM of lung in adults, diagnosed from June 2015 to May 2023, were collected from the Department of Pathology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, China. Their histopathological features were correlated with probable development into lung cancer. Next-generation sequencing was performed on the benign and malignant areas of all cases.Results:The pathological classification of all cases were of CCAM of lung type 1. There were 4 male and 9 female cases, age ranged from 18 to 65 years, with a mean age of 41 years. Six cases were accompanied by lung cancer, all of them were mucinous adenocarcinoma. Next-generation sequencing showed no gene mutation in 2 of the 13 cases; KRAS mutations in exon 2 were detected in 7 cases, in which there were 6 cases complicated with lung mucinous adenocarcinoma and no matter in the malignant or benign regions, the same case exhibited the same mutation sites in KRAS gene.Conclusions:CCAM of the lung is a congenital disease, and in adults, type 1 is most commonly found in the pathological classification, and it is often accompanied by cancer. Gene mutations are frequently detected in CCAM of the lung, KRAS being the most recurrent mutation which may play an important role in the carcinogenesis.

Objective    To compare the clinical effects of segmentectomy and lobectomy for ≤2 cm lung adenocarcinoma with micropapillary and solid subtype negative by intraoperative frozen sections. Methods    The patients with adenocarcinoma who received segmentectomy or lobectomy in multicenter from June 2020 to March 2021 were included. They were divided into two groups according to a random number table, including a segmentectomy group (n=119, 44 males and 75 females with an average age of 56.6±8.9 years) and a lobectomy group (n=115, 43 males and 72 females with an average of 56.2±9.5 years). The clinical data of the patients were analyzed. Results    There was no significant difference in the baseline data between the two groups (P>0.05). No perioperative death was found. There was no statistical difference in the operation time (111.2±30.0 min vs. 107.3±34.3 min), blood loss (54.2±83.5 mL vs. 40.0±16.4 mL), drainage duration (2.8±0.6 d vs. 2.6±0.6 d), hospital stay time (3.9±2.3 d vs. 3.7±1.1 d) or pathology staging (P>0.05) between the two groups. The postoperative pulmonary function analysis revealed that the mean decreased values of forced vital capacity and forced expiratory volume in one second percent predicted in the segmentectomy group were significantly better than those in the lobectomy group (0.2±0.3 L vs. 0.4±0.3 L, P=0.005; 0.3%±8.1% vs. 2.9%±7.4%, P=0.041). Conclusion    Segmentectomy is effective in protecting lungs function, which is expected to improve life quality of patients.

The International Agency for Research on Cancer (IARC) published the World Health Organization (WHO) classification of thoracic tumors (5th edition) in May 2021, only six years after the 4th edition of WHO Classification. With the application of low-dose spiral computed tomography (CT) as an early screening method for lung tumors in recent years, lung adenocarcinoma has become the main type of disease in many hospital surgical treatments. The WHO classification serves as the authoritative guide for pathological diagnosis, and any slight change in the classification is at the heart of pathologists, clinicians and patients. Adenocarcinoma in situ is a newly added type of adenocarcinoma diagnosis in the 4th edition of the WHO classification, and it is also the focus of clinical treatment and research at home and abroad in recent years. Because its catalog position has been adjusted in the 5th edition of the WHO classification, there has been a huge controversy and discussion among clinicians and patients that "adenocarcinoma in situ was excluded from the category of malignant tumors". This article will briefly explain the origin of the diagnosis of lung adenocarcinoma in situ, the adjustment of the new classification catalog, and whether adenocarcinoma in situ is benign or malignant.
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Adenocarcinoma in Situ/pathology* ; Adenocarcinoma of Lung/diagnostic imaging* ; Humans ; Lung Neoplasms/pathology* ; Neoplasm Staging

Objective:To investigate the clinical pathological features of primary pulmonary and tracheal glomus tumors.Methods:The clinical and pathological features of 11 cases (4 cases from Shanghai Pulmonary Hospital, Tongji University School of Medicine, China and 7 cases from Fudan University Shanghai Cancer Center, China) of respiratory glomus tumor diagnosed from 2010 to 2019 were analyzed, and reviewed in light of the relevant literature.Results:In the 11 cases, there were 5 males and 6 females, with the onset ages of 29?66 years (median age of 43). Six tumors were located in the lung, and 5 in the trachea. The tumor diameters ranged 1.0?7.5 cm, with the average diameter of 2.6 cm. At low magnification, the tumors were diffuse or lobulated in shape. The tumor cells composed of sheets of oval to short spindle cells, with sharply defined cell border and prominent branching thin-walled vessels. Among the 4 benign glomus tumors, one was classified as benign symplastic glomus tumor owing to the hyperchromatic or degeneration nuclei. Two cases were classified as glomus tumors of uncertain malignant potential, on the account of cellular atypia and rare atypical mitotic figures. Five cases were classified as malignant glomus tumors, owing to the tumor necrosis, vascular invasion, marked nuclear atypia, prominent nucleoli and brisk mitoses (2-20/10HPF) including pathological mitotic figures. The tumor cells showed strong immunostaining for SMA, vimentin, type Ⅳ collagen and caldesmon to different extents, while CD34, cytokeratin and S-100 stains were negative. One of the cases was positive for desmin, and one case positive for synaptophysin. Follow-up information was available in 8 patients with the duration ranging from 6 to 95 months. At the end of the follow-up, 6 patients were alive without recurrence or metastasis, and two of the patients with malignant glomus tumors died.Conclusions:Primary pulmonary and tracheal glomus tumors is rare. Among the reported cases, malignant glomus tumor is the most frequent, followed by benign glomus tumors and uncertain malignant potential glomus tumors. Glomus tumors show sheet-like growth pattern and clusters of round epithelioid cells with numerous vascular spaces. They can be easily misdiagnosed as carcinoid tumor. The final diagnosis should be combined with immunohistochemical staining, such as SMA, caldesmon and vimentin.