中华病理学杂志最新文献

Objective: To investigate the clinicopathological features, immunophenotype, and gene rearrangement status of hyalinizing clear cell carcinoma (HCCC) of the salivary glands, in order to better understand this rare tumor and improve its precision diagnosis and treatment. Methods: A total of 65 cases of salivary gland HCCC diagnosed at the Peking University School and Hospital of Stomatology, Beijing, China between January 2001 and May 2024 were collected. Clinical features, pathological characteristics, EWSR1 gene rearrangement, and follow-up data were analyzed. Results: There were 33 males and 32 females. The age of the patients ranged from 22 to 85 years, with a median age of 54.0 (40.0, 63.5) years. 93.8% (61/65) of the tumors occurred in the minor salivary glands, most commonly in the palate. Microscopically, the tumors were mainly composed of clear tumor cells. Squamous differentiation was observed in 66.2% (43/65) of the tumors, and mucinous cells in 36.9% (24/65). The tumor stroma showed delicate fibrous septa or hyalinized sheets between tumor nests. Lymph node metastasis occurred in 12.3% (8/65) of the cases, and high-grade transformation was observed in 6.2% (4/65). Tumor cells were all positive for p40 and p63, while SOX10 was positive in 12.3% (8/65) of them. Myoepithelial markers were negative. EWSR1 gene rearrangement was detected in 96.6% of the tumors. Follow-up data showed a 5-year overall survival rate of 93.8%, a local recurrence rate of 9.2%, and a distant metastasis rate of 4.6%. Conclusions: HCCC predominantly arises in minor salivary glands and generally has a favorable prognosis. However, a small proportion of the cases may show high-grade transformation, lymph node metastasis, local recurrence, or distant metastasis. It thus requires long-term and regular follow-up. Accurate diagnosis should be based on a comprehensive assessment of histopathological features, immunophenotype, and gene fusion status.

Objective: To analyze the cytological, histological, immunohistochemical, and molecular pathological features of hyalinizing trabecular tumor (HTT). Methods: Clinical and pathological data of the HTT cases diagnosed at Shanghai Sixth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine between 2020 and 2024 were collected and analyzed. HE staining, special staining, immunohistochemical staining, and next-generation sequencing were performed on all cases. Results: Among the 10 HTT patients, 4 were male and 6 were female. The age at onset ranged from 29 to 85 years, with a median age of 49 (35,61) years. The maximum tumor diameter ranged from 0.3 to 5.3 cm. Cytologically, the smears were hypercellular and showed tumor cells arranged in nested clusters with visible basement membrane-like material. The nuclei were oval with finely granular chromatin, and nuclear pseudoinclusions were readily identifiable. Histologically, the tumors were well demarcated. The tumor cells were arranged in a paraganglioma-like pattern, exhibiting typical nuclear features of papillary thyroid carcinoma and psammoma bodies. Yellow bodies were observed in the cytoplasm. The stroma was rich in hyalinized material, which was periodic acid-Schiff stain (PAS)-positive. Immunohistochemically, the tumor cells showed diffuse expression of TTF-1 and focal expression of thyroglobulin. Aberrant immunoreaction with Ki-67 was present in the cytoplasm and membrane of the tumor cells. Molecular testing was performed on 8 cases. The PAX8-GLIS3 gene fusion was detected in 7 cases. Among these fusion-positive cases, 4 exhibited additional genetic abnormalities: one concurrent TSHR point mutation (p.D617H); one concurrent HRAS point mutation (p.Q61R); one concurrent LRP1B point mutation (p.S1752L), SUGCT point mutation (p.K137), and TERT point mutation (p.P785L); one concurrent MTOR mutation (7528+27A>T) and FLT3 mutation (p.E77K). The key initiating factors for thyroid carcinoma, including the BRAF V600E mutation and RET rearrangements, were absent in all cases tested. Conclusions: Cellular pleomorphism, yellow bodies and basement membrane-like material constitute important cytological and histological features for the differential diagnosis of HTT. Immunophenotypically, thyroglobulin may show focal expression, while Ki-67 is typically localized in the tumor cell membrane and cytoplasm. This study also demonstrates that PAX8-GLIS3 fusion is a characteristic molecular abnormality in HTT, although cases with wild type of GLIS gene may also present. Although rare, HTT may harbor point mutations in HRAS and TSHR, and other uncommon genetic alterations.

Objective: To investigate the clinicopathological features of SMARCA4-deficient uterine sarcoma. Methods: Five cases of SMARCA4-deficient uterine sarcoma at the Department of Pathology, the First Affiliated Hospital of Nanjing Medical University from 2018 to 2024 were collected. The morphological and immunohistochemical features were observed and analyzed. A follow-up study was also carried out. Results: Five female patients, aged 24, 54, 56, 61, and 41 years, respectively, presented with vaginal bleeding or abdominal pain. All patients had imaging findings of intracavitary lesion in the uterus, with tumor sizes ranging from 3.0 cm to 8.8 cm. The patients were followed up for 2 to 14 months. Case 1 died 9 months after surgery, whereas the remaining four patients were still alive. Histologically, the tumor cells exhibited a diffuse growth pattern, with an infiltration depth involving more than half of the myometrium. Portions of the interstitium appeared sclerosed. Benign endometrial glandular structures were observed in a leaf-like or fissured pattern, resembling those of uterine adenosarcoma. The tumor cells were large epithelioid with abundant or faintly eosinophilic cytoplasm, and the nuclei were moderately to markedly atypia with prominent nucleoli and brisk mitosis. Rhabdoid cells were seen. Some areas showed small round blue cells, with occasional spindle cells and myxoid stroma. Additionally, widespread or focal lymphovascular space invasion was observed within the myometrium. All five cases exhibited absence of SMARCA4 (BRG1) expression and retained SMARCB1 (INI1). Claudin4 expression was negative. There was no deficient expression of mismatch repair proteins MLH1, PMS2, MSH2 and MSH6. p53 showed wild-type expression. Ki-67 index ranged from 30% to 60%. CKpan, CK7, ER, PR, and PAX8 were negative. Conclusions: SMARCA4-deficient uterine sarcoma is rare, highly aggressive, and has a poor prognosis. The tumor exhibits a broad morphological spectrum, with rhabdoid cells and adenosarcoma-like structures serving as important diagnostic clues. The absence of BRG1 expression lends support to a definitive diagnosis.