[Clinicopathological and genetic characteristics of congenital cystic adenomatoid malformation of lung and its associated lung cancer in adults].

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.

[Clinicopathological features and prognosis of SMARCA4-deficient non-small cell lung carcinoma: an analysis of 127 cases].

Objective: To investigate and elucidate the clinicopathological and prognostic characteristics of SMARCA4-deficient non-small cell lung cancer. Methods: The clinicopathological and prognostic data were collected in 127 patients with SMARCA4-deficient non-small cell lung cancer diagnosed in Shanghai Pulmonary Hospital, Shanghai, China from January 2020 to March 2022. The variation and expression of biomarkers related to treatment were retrospectively reviewed. Results: One hundred and twenty-seven patients were eligible for enrollment. Among them 120 patients (94.5%) were male and 7 cases (5.5%) were female, while the average age was 63 years (range 42-80 years). There were 41 cases (32.3%) of stage Ⅰ cancer, 23 cases (18.1%) of stage Ⅱ, 31 cases (24.4%) of stage Ⅲ and 32 cases (25.2%) of stage Ⅳ. SMARCA4 expression detected by immunohistochemistry was completely absent in 117 cases (92.1%) and partially absent in 10 cases (7.9%). PD-L1 immunohistochemical analyses were performed on 107 cases. PD-L1 was negative, weakly positive and strongly positive in 49.5% (53/107), 26.2% (28/107) and 24.3% (26/107) of the cases, respectively. Twenty-one cases showed gene alterations (21/104, 20.2%). The KRAS gene alternation (n=10) was most common. Mutant-type SMARCA4-deficient non-small cell lung cancer was more commonly detected in females, and was associated with positive lymph nodes and advanced clinical stage (P<0.01). Univariate survival analysis showed that advanced clinical stage was a poor prognosis factor, and vascular invasion was a poor predictor of progression-free survival in patients with surgical resection. Conclusions: SMARCA4-deficient non-small cell lung cancer is a rare tumor with poor prognosis, and often occurs in elderly male patients. However, SMARCA4-deficient non-small cell lung cancers with gene mutations are often seen in female patients. Vascular invasion is a prognostic factor for disease progression or recurrence in patients with resectable tumor. Early detection and access to treatment are important for improving patient survivals.

[Application of the WHO Classification of Thoracic Tumors (2021) grading system in invasive pulmonary adenocarcinoma and its correlation with the targeted genes' variations].

Objective: To investigate the applicability of the 2021 WHO classification of thoracic tumors' new grading system for invasive pulmonary adenocarcinoma (IPA) with different clinical stages and its correlation with the characteristics of targeted genes' variation. Methods: A total of 2 467 patients with surgically resected primary IPA in Shanghai Pulmonary Hospital, Shanghai, China from September to December 2020 were retrospectively analyzed. Eligible cases were graded using the new grading system of IPA of the 2021 WHO classification of thoracic tumors. The clinicopathological data and targeted-gene abnormality were collected. The utility of new grading system of IPA in different clinical stages was investigated. The correlation of clinicopathological features and targeted-gene abnormality in different grades of IPA were compared. Results: All 2 311 cases of IPA were included. There were 2 046 cases of stage Ⅰ IPA (88.5%), 169 cases of stage Ⅱ (7.3%), and 96 cases of stage Ⅲ (4.2%). According to the new classification system of IPA, 186 cases (9.1%), 1 413 cases (69.1%) and 447 cases (21.8%) of stage-Ⅰ adenocarcinoma were classified as Grade 1, Grade 2 and Grade 3, respectively. However, there were no Grade 1 adenocarcinomas in stages Ⅱ and Ⅲ cases. Among stage-Ⅱ and Ⅲ IPA cases, there were 38 Grade 2 cases (22.5%) and 131 Grade 3 cases (77.5%), and 3 Grade 2 cases (3.1%) and 93 Grade 3 cases (96.9%), respectively. In stage-Ⅰ cases, no tumor cells spreading through airspace (STAS), vascular invasion or pleural invasion was found in Grade 1 of IPA, while the positive rates of STAS in Grade 2 and 3 IPA cases were 11.3% (159/1 413) and 73.2% (327/447), respectively. There was a significant difference among the three grades (P<0.01). Similarly, the rates of vascular and pleural invasion in Grade 3 IPA cases were 21.3% (95/447) and 75.8% (339/447), respectively, which were significantly higher than those of 1.3% (19/1 413) and 3.0% (42/1 413) in Grade 2 (P<0.01). EGFR mutational rates in Grades 1, 2 and 3 IPA were 65.7% (94/143), 76.4% (984/1 288) and 51.3% (216/421), respectively. The differences among the three grades were statistically significant (P<0.01). No fusion genes were detected in Grade 1 IPA, while the positive rates of ROS1 and ALK fusion genes in Grade 3 were 2.4% (10/421) and 8.3% (35/421), respectively, which were significantly higher than that of 0.5% (7/1 288) and 1.6% (20/1 288) in Grade 2 (P<0.01). In stage-Ⅱ cases, only EGFR mutation rate in Grade 2 adenocarcinoma (31/37, 83.8%) was higher than that in Grade 3 adenocarcinoma (71/123, 57.7%; P<0.01). However, the correlation between the new grade system of IPA and the distribution characteristics of targeted-gene variation cannot be evaluated in stage Ⅲ cases. Conclusions: The new grading system for IPA is mainly applicable to clinical stage-Ⅰ patients. Tumor grades of IPA are strongly correlated with the high-risk factors of prognosis and the distribution features of therapeutic targets. It is of great significance and clinical value to manage postoperative patients with early-stage IPA.

[Pulmonary granular cell tumors: a clinicopathological analysis of five cases].

Objective: To investigate the clinicopathological features of pulmonary granular cell tumors (pGCTs) and to improve the diagnostic accuracy of the tumor. Methods: A total of 5 pGCTs were diagnosed from February 2016 to January 2022 at Shanghai Pulmonary Hospital, Tongji University School of Medicine and Fudan University Shanghai Cancer Center, China. Immunohistochemical staining, and analysis of the clinicopathological characteristics were performed. Results: The average age of the pGCTs patients was 46 years (ranging from 24 to 54 years), with 3 females and 2 males. One case occurred in the bronchus with multiple nodules in the lung, 2 cases occurred in the bronchial opening, and 2 cases were solitary nodules in the lung. The maximum diameter of the tumors ranged from 12 to 15 mm (mean size 14 mm). Microscopically, the tumor showed infiltrative growth and consisted of round, oval or polygonal cells. Abundant eosinophilic cytoplasm was noted, and the nucleoli were prominent. None of the 5 cases showed any mitosis or necrosis. Immunohistochemical and histochemical study showed positive staining for S-100 (5/5), SOX10 (5/5), Vimentin (5/5), TFE3 (4/5), PAS (3/5), and amylase-digested-PAS (3/5), while 4 cases were negative for CD68. TFE3 FISH analyses on 2 cases showed that no signal abnormality was detected in these 2 cases. The average proliferation index of Ki-67 was 2.2% (range 0-5%). There was no recurrence in 4 cases of pGCTs with a follow-up time ranging from 2 months to 60 months. Conclusions: pGCTs are very rare tumors, most likely originating from Schwann cells. Immunohistochemical staining is the conventional diagnostic tool for pGCTs diagnosis. Recognition of this entity is essential for pathologists to avoid misdiagnosis and unnecessary treatments.

[Clinicopathological and genetic characteristics of bronchial sialadenoma papilliferum: report of four cases].

Objective: To investigate the clinicopathological, immunophenotypic, and molecular genetic features of bronchial sialadenoma papilliferum (BSP). Methods: Four cases of BSP collected at the Shanghai Pulmonary Hospital from May 2018 to June 2021 were retrieved and analyzed. These cases were evaluated for their clinical, histological, immunohistochemical (IHC) and genomic features. The patients were followed up and relevant literature was reviewed. Results: All four patients were male, aged from 55 to 75 years (mean 62 years), with tumor diameter of 6 to 21 mm (mean 13.5 mm), and lesions were located in the left lower lobe (n=2), right lower lobe (n=1), and trachea (n=1). They were characterized by a combination of surface exophytic endobronchial papillary proliferation and an endophytic two-cell layered ductal structure. IHC staining showed that CK7 and EMA were strongly positive in ductal epithelium; p63, p40, CK5/6 were positive in ductal and papillary basal cells; SOX10 was positive in ductal epithelium and basal cells; S-100 was positive in basal cells and ductal epithelium in two cases. Next generation sequencing showed that two cases harbored BRAF V600E mutation. Conclusions: BSP is an extremely rare primary lung tumor arising from the salivary gland under bronchial mucosa. The primary treatment choice of this tumor is complete surgical resection. The diagnosis and differential diagnosis of this tumor depend on classic histomorphologic and IHC features, and BRAF V600E gene mutation can be detected.

[Primary lung salivary gland-type duct carcinoma: a clinicopathological analysis of two cases and review of literature].

Objective: To investigate the clinicopathological features, diagnostic criteria and differential diagnosis of primary salivary gland-type duct carcinoma of lung(LSDC). Methods: Two patients with LSDC after surgical resection in Shanghai Pulmonary Hospital from 2020 to 2021 were included; their clinical parameters as well as pathological, immunohistochemical and molecular characteristics of the tumors were analyzed. The relevant literature was also reviewed. Results: Both patients were male, aged 49(case 1) and 64(case 2) years, respectively, and with a history of smoking. The chest computed tomography scan showed both lesions to be centrally located. Gross examination showed the maximum diameters were 16 mm and 35 mm, respectively. The histomorphology of LSDC resembled ductal carcinoma of breast, with intraductal islands of neoplastic cells, which also formed solid nests, papillary, micropapillary and cribriform structures. There was frequent accompanying comedo-like necrosis. The neoplasm cells were markedly heteromorphic, possessing large irregular nuclei with prominent nucleoli, abundant eosinophilic or clear cytoplasm, and mitotic figures were common. Both cases of LSDC were immunoreactive for CKpan, CK7, AR, HER2 staining was (2+) and were negative for TTF1, Napsin A, p40, GATA3, mammaglobin, GCDFP15, SOX10, PSA, P504S, ER, PR, vimentin, S-100, SMA, CK5/6 and p63. The tumor showed double-layer cell structure of the duct, and some basal cells/myoepithelial cells expressed p40 and CK5/6. Case 1 had no gene mutation while case 2 harbored TP53 and KMT2A gene mutation detected by next generation sequencing. Conclusions: LSDC is a very rare and highly aggressive salivary-type malignant tumor. The postoperative diagnosis mainly depends on histopathology and immunohistochemistry, attention should be paid to differential diagnosis to prevent missed diagnosis.

[Pathological assessment of non-small cell lung cancer resection specimens after neoadjuvant therapy].

Objective: To pathologically evaluate the surgically resected specimens of three different therapies (neoadjuvant chemotherapy, neoadjuvant targeted therapy and neoadjuvant immunotherapy combined with chemotherapy) for non-small cell lung cancer. Methods: One-hundred and thirteen cases of post neoadjuvant therapy non-small cell lung cancer specimens were collected at Tongji University Affiliated Shanghai Pulmonary Hospital from January 2000 to March 2020. There were ninty patients receiving neoadjuvant chemotherapy (chemotherapy group;26 cases of adenocarcinoma and 64 cases of squamous cell carcinoma), 13 patients receiving neoadjuvant targeted therapy (targeted group;13 cases of adenocarcinoma) and 10 patients receiving neoadjuvant immunotherapy combined with chemotherapy (immune combined chemotherapy group;4 cases of adenocarcinoma and 6 cases of squamous cell carcinoma). They were evaluated for histologic tumor regression responses (necrosis, inflammatory cell infiltration, cholesterol crystal deposition, foam cell infiltration, reactive granuloma and interstitial collagenous formation) and pathological responses [main pathological response (MPR) and complete pathological response (PCR)]. Results: Chemotherapy group, targeted group and immune combined chemotherapy group all showed degenerative changes in residual tumor cells, increased atypia, various degrees of necrosis, foam cell aggregation, cholesterol cleft, inflammatory cell infiltration, and reactive granuloma in the tumor bed. Histologic characteristics of tumor regression reaction were not different between these three groups (P>0.05); the highest percentage of necrosis in the targeted group and immune combined chemotherapy group was only 10% and 20%, respectively, while that in the chemotherapy group was as high as 80%. One case of adenocarcinoma in immune combined chemotherapy group had tumor regression bed. The MPR rates of adenocarcinoma in chemotherapy group and squamous cell carcinoma in chemotherapy group were 35% (9/26) and 64% (41/64), respectively; the MPR ratio of targeted group was 2/13; the MPR ratio of adenocarcinomain immune combined chemotherapy group and squamous cell carcinoma in immune combined chemotherapy group were 2/4 and 2/6, respectively. The PCR rates of adenocarcinoma in chemotherapy group and squamous cell carcinoma in chemotherapy group were 11% (3/26) and 3% (2/64), respectively; the PCR ratio of targeted group was 0/13; the PCR ratio of adenocarcinomain immune combined chemotherapy group and squamous cell carcinomain immune combined chemotherapy group were 0/4 and 1/6, respectively. Conclusions: Different neoadjuvant therapy may cause various histopathological changes in non-small cell lung cancer: more necrosis is noted in the chemotherapy group and regression bed frequently appears in the immune combined chemotherapy group. In the immune combined chemotherapy group, there are significant lymphoplasmacytic infiltration and lymphoid follicle formation in the lung parenchyma beside the tumor bed.

[Often misdiagnosed primary pleural epithelioid hemangioendothelioma: a clinicopathological analysis of five cases].

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of primary pleural epithelioid hemangioendothelioma (EHE). Methods: Five cases of pleural EHE diagnosed from 2012 to 2019 in the Shanghai Pulmonary Hospital of Tongji University, China, were collected. They were subjected to review of clinical and image data, reevaluation of histological sections, immunohistochemistry study, clinical follow up and literature review. Results: There were 1 male and 4 females (male to female ratio of 1∶4). The age ranged 19‒58 years, with a median age of 52 years. There was no smoking history in all 5 cases. Clinical manifestations included chest distress, chest pain, cough and hemoptysis. CT scan showed pleural effusion, pleural thickening, multiple pleural nodules and pneumothorax. All of the 5 cases were diagnosed based on thoracoscopic biopsies, which were performed for the suspicion of malignancy in 3 cases and for the suspicion of tuberculosis upon the failure of anti-tuberculosis treatment in 2 cases. Histologically, the tumors grew in the mesenchyme, forming cords, nests and solid sheets. The tumor cells were round, oval, short spindle, and polygonal in shape. They were epithelioid and had abundant cytoplasm and prominent nucleoli. Blister cells (vacuoles in cytoplasm) could be seen, and for mednewly-generated vessel lumen. Mucoid degeneration and collagenization were common in the tumor stroma. The positive-stainin grate was 5/5 for vimentin, 5/5 for D2-40, 4/5 for CD31, 4/5 for ERG, 4/5 for CAMTA1, 2/5 for CD34 and 2/5 for CKpan. WT1, calretinin and CK5/6 were all negative. The follow-up time ranged from 4‒18 months. During the follow-up, 4 patients were treated with chemotherapy (2 patients died, and 2 survived with tumor), and 1 patient lost to the follow-up. Conclusions: Primary pleural EHE is rare. Its imaging and clinical features are very similar to those of tuberculosis. The correct diagnosis relies on pathological biopsy. Tumor cells are epithelioid. When CD34 is negative and D2-40 is positive, it is easy to be misdiagnosed as malignant mesothelioma. The combination of CD31, ERG and CAMTA1, which have high specificity of EHE, is helpful for the differential diagnosis.

[Comparison of epidermal growth factor receptor (EGFR) gene T790M mutation by droplet digital PCR and Super-ARMS PCR in plasma ctDNA samples of non-small cell lung cancer patients with the resistance to EGFR-tyrosine kinase inhibitor].

Objective: To compare droplet digital PCR (ddPCR) and Super-amplification refractory mutation system (ARMS) in the detection of T790M mutation of epidermal growth factor receptor (EGFR) in the plasma of non-small cell lung cancer patients who had developed resistance to EGFR tyrosine kinase inhibitor (TKI) , and to investigate the clinical application of ddPCR. Methods: Plasma samples were collected from non-small cell lung cancer patients who had acquired EGFR-TKI resistance at Shanghai Pulmonary Hospital, Tongji University, from May 2017 to November 2017. Extracted ctDNA was analyzed by ddPCR and Super-ARMS to evaluate the T790M mutation status of EGFR gene. Results: A total of 37 patients with activating EGFR mutation that acquired resistance to EGFR-TKI were selected in the study, including 17 male and 20 female with a median age of 64 years (range 40-83 years). Before TKI treatment, all the patients harbored EGFR inhibitor sensitive mutations but without T790M mutation. After acquiring resistance to EGFR-TKI treatment, the T790M mutation rate detectable by ddPCR was 45.9% (17/37). In contrast, the mutation rate of T790M detectable by Super-ARMS was 35.1% (13/37, P<0.05). For the 13 positive cases detected by Super-ARMS (ΔCt<8), they were all positive by ddPCR assay; Among the 10 negative cases detected by Super-ARMS (ΔCt≥8), there were 3 cases positive by ddPCR assay. For patients without ΔCt by Super-ARMS assay, there was one weak positive case detectable by ddPCR assay. Among 17 EGFR T790M positive patients, 9 received EGFR inhibitor Osimertinib treatment, and 7 of them had good therapeutic response after the treatment. Conclusions: While a significant correlation between the two methods is shown. ddPCR is more sensitive than Super-ARMS in the detection of EGFR T790M mutation, indicating that it is a better method in guiding target drug therapy of non-small cell lung cancer patients after acquiring the resistance to EGFR-TKI.

miR-129-5p suppresses breast cancer proliferation by targeting CBX4.

Deregulation of microRNA (miRNA) is closely related to cancer development and progression. Our previous study identified that miR-129-5p suppresses proliferation and metastasis in breast cancer cells. Herein, we determined that CBX4 is a miR-129-5p target gene. CBX4 is up-regulated in breast cancer tissues and while its over-expression promotes cell proliferation, its knockdown suppresses cell proliferation in breast cancer cells. Furthermore, CBX4 mediates miR-129-5p-induced inhibition of cell proliferation and negatively correlates with the expression of miR-129-5p expression. These combined results suggest that CBX4 is an oncogene in breast cancer cells, and that it may provide a novel therapeutic strategy for breast cancer treatment.

[Clinicopathologic features and genetic profile of the redefined large cell lung carcinoma].

Objective: To investigate the clinicopathologic features and genetic profile of large cell lung carcinoma (LCC) redefined by new classification. Methods: Basing on 2015 WHO classification criteria in redefining large cell lung carcinoma, the expression of specific markers (TTF1, Napsin A, p40, CK5/6, CK, vimentin and ZEB1) was detected by immunohistochemistry and D-PAS staining in 303 surgically-removed lung specimens previously diagnosed as large cell lung carcinoma. The clinicopathologic and genetic characteristics (including EGFR, KRAS, BRAF, ALK and ROS1 gene mutation) were analyzed. Results: Based on the new definition of LCC, 116 cases (116/303, 38.3%) of LCC formerly diagnosed were reclassified as solid adenocarcinoma, 49 cases (49/303, 16.2%) as squamous cell carcinoma, 6 cases (6/303, 2.0%) as adenosquamous carcinoma, 22 cases (22/303, 7.3%) as spindle cell carcinoma and only 110 cases (110/303, 36.3%) as large cell carcinoma. Redefined LCCs were characterized as middle-age (range 40-80), male (102/110, 92.7%) and smoking patients (64/110, 58.2%) with intermediate-advanced stage. Among 110 cases, 9 cases with EGFR mutation and 10 cases with KRAS mutation and 1 case with ALK fusion were found. No BRAF and ROS1 alterations were identified. Conclusions: According to the new classification, LCCs formerly diagnosed are mostly reclassified as adenocarcinoma and non-keratinizing squamous cell carcinoma. The newly defined LCC may significantly benefit from clinical therapy.

[Clinicopathologic features and epidermal growth factor receptor gene mutation of primary pulmonary mucoepidermoid carcinoma].

OBJECTIVE: To investigate the clinicopathological features and epidermal growth factor receptor (EGFR) gene mutation of primary pulmonary mucoepidermoid carcinoma (PMC). METHODS: Fifth-five cases of PMC were included in the study; their clinicopathological, immunohistochemical features were evaluated, and in 31 cases, paraffin embedded specimens were subjected to mutation analysis of exons 18, 19, 20 and 21 of the EGFR gene by ARMS method. RESULTS: There were 32 females and 23 males. The patients' age ranged from 11 to 68 years(mean 36 years). The tumor size ranged from 0.7 to 5.5 cm(mean 2.4 cm). The tumors were located in the segmental bronchus and upper segmental bronchus. The tumors were well-demarcated, had no obvious capsules, and protruded into the bronchial lumen. Microscopically, there were three types of tumor cells including squamous cells, mucin-producing cells and intermediate cells. Fifty-three cases were low grade, two were high grade and both showed lymph node metastases. Immunohistochemically the tumor cells were uniformly negative for TTF1, Napsin A and ALK (Ventana D5F3) in all 55 cases. The tumor cells were positive for CK7, and some squamous and intermediate cells were positive for p63 and CK5/6 in all 55 cases; whereas they were positive for p40 in 53 cases. The mucin-producing cells were negative for CK5/6, p63 and p40, but were positive for PAS in all 55 cases. The Ki-67 positive rate was <10% in the low grade PMC, and was about 80%-90% in the high grade cases. Follow-up information was available in 37 patients, with no recurrence or death. There were no EGFR gene mutations in all 31 patients of PMC. CONCLUSIONS: PMC is a rare malignant salivary gland-type tumor occurring mainly in the central trachea of young patients.Most PMCs are low grade with good prognosis. The rate of lymph node metastasis of high grade PMC is high. Diagnosing PMC in small biopsies could be problematic. The lack of TTF1 expression is helpful to differentiate from other primary lung cancers. There is no EGFR gene mutation in PMC.