Preliminary study on clinicopathological features of renal mucinous tubular and spindle cell carcinoma / 肿瘤

ABSTRACT

Objective: To explore the clinicopathological features and prognosis of mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney in order to improve the understanding of the tumor. Methods: The clinical and pathological information of 15 patients with MTSCC in 7 hospitals were retrospectively collected and analyzed from July 2010 to July 2018. The sections were reviewed by two high-seniority pathologists. The EnVision two-step immunohistochemical staining technique was used to detect the expressions of villin, cytokeratin 7 (CK7), epithelial membrane antigen (EMA), alpha-methylacyl-CoA racemase (AMACR), transducin-like enhancer of split 1 (TLE1), hepatocyte nuclear factor-1p (HNF-1p)and kidney specific calcium binding protein (Ksp-cadherin). The fluorescence in situ hybridization (FISH) was used to detect the synovial sarcoma translocation (SYT)-synovial sarcoma X chromosome breakpoint (SSX) fusion gene in the patients with sarcomatoid changes and positive immunohistochemical staining of TLE1. Finally, the prognostic data of all patients and the relevant literature were reviewed. Results: Among 15 patients with MTSCC, seven of the patients were male and the other eight were female, with an average age of 62 years (ranging from 48 to 75 years). The tumors were found by chance in 12 patients during physical examination, and the other 3 patients developed clinical symptoms such as frequent urine pain or hematuria, including 1 patient with a history of renal calculi for 15 years. The cut surface of tumor is firm and grey or yellow. Except for 2 cases, the majority of tumors were well-circumscribed. Microscopically, 1 case showed neoplastic necrosis, 13 cases showed a mixture of mucinous stroma, tubules and spindle cells, 1 case was mainly composed of spindle cells and mucus, and 1 case was mainly composed of tubule and mucus. Some tumors were with obvious clear cytoplasmic changes, and two cases were accompanied by sarcomatoid differentiation. The immunohistochemical results showed that the positive rates of villin, CK7, EMA, AMACR, TLE1, HNF-1 p and Ksp-cadherin were 20.0% (3/15), 80.0% (12/15), 93.3% (14/15), 80.0% (12/15), 20.0% (3/15), 20.0% (3/15), 93.3% (14/15) and 13.3% (2/15), respectively; the result of FISH excluded synovial sarcoma. Eight patients were followed up wihout other treatment after operation. Bone metastasis occurred in half a year after operation in one patient with follow-up information, while no evidence of local recurrence or distant metastases was identified in the other 7 patients until now. Conclusion: A few cases of MTSCC can metastasize and belong to malignant tumors. The positive expressions of AMACR, CK7 and villin in some cases suggests that the tumor has both proximal and distal renal tubular origins. The positive expression of HNF-ip is correlated with the histological characteristics of MTSCC clear cytoplasm.