SRF-rearranged cellular perivascular myoid tumor: a clinicopathological analysis of two cases
10.3760/cma.j.cn112151-20230727-00033
- VernacularTitle:SRF易位富于细胞性血管周肌样肿瘤2例临床病理学分析
- Author:
Tangchen YIN
1
;
Mengyuan SHAO
;
Meng SUN
;
Lu ZHAO
;
Weng I LAO
;
Qianlan YAO
;
Qianming BAI
;
Lin YU
;
Xiaoyan ZHOU
;
Jian WANG
Author Information
1. 复旦大学附属肿瘤医院病理科 复旦大学上海医学院肿瘤学系 复旦大学病理研究所，上海 200032
- Keywords:
Soft tissue neoplasms;
Genes;
Perivascular cell tumor
- From:
Chinese Journal of Pathology
2024;53(1):64-70
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinicopathological features, immunophenotype, diagnosis and differential diagnosis of SRF-rearranged cellular perivascular myoid tumor.Methods:Two cases of SRF-rearranged cellular perivascular myoid tumor diagnosed in the Department of Pathology, Fudan University Shanghai Cancer Center from October 2021 to March 2022 were collected. Immunohistochemical staining, fluorescence in-situ hybridization (FISH) and next-generation sequencing (NGS) were performed, and the literature was reviewed.Results:Case 1, a 3-month-old boy presented with a painless tumor of the scalp, measuring about 2 cm in diameter. Case 2, a 3-year-old girl complained with a painless tumor of the knee, measuring approximately 1.5 cm in diameter. Microscopically, the tumor had a clear boundary and showed multinodular growth. The tumor was mainly composed of spindle cells arranged in long intersecting fascicles associated with thin, slit-like or branching ectatic vessels, focally forming hemangiopericytoma-like appearance. The tumor cells were abundant, but there was no obvious atypia. Mitotic figures (3-4/10 HPF) were noted. H-caldesmon and SMA were positive in both cases. Case 1 showed diffuse and strong positivity for Desmin, and focally for CKpan. Ki-67 proliferation index was 20% and 30%, respectively. FISH displayed NCOA2 gene translocation in case 1 and the RELA gene translocation in case 2. NGS detected the SRF-NCOA2 gene fusion in case 1 and the SRF-RELA gene fusion in case 2. Both patients underwent local excisions. During the follow-up of 5-14 months, case 1 had no local recurrence, while case 2 developed local recurrence 1 year post operatively.Conclusions:SRF-rearranged cellular perivascular myoid tumor is a novel variant of perivascular cell tumor, which tends to occur in children and adolescents. The tumor forms a broad morphologic spectrum ranging from a pericytic pattern to a myoid pattern, and include hybrid tumors with a mixture of pericytic and myoid patterns. Due to its diffuse hypercellularity and increased mitotic figures and smooth muscle-like immunophenotype, the tumor is easy to be misdiagnosed as myogenic sarcomas. The tumor usually pursues a benign clinical course and rare cases may locally recur.
