Clinicopathological and molecular genetic characteristics of nodular fasciitis in unusual sites
10.3760/cma.j.cn112151-20210917-00688
- VernacularTitle:少见部位结节性筋膜炎临床病理及分子遗传学特征
- Author:
Qiuyu LIU
1
;
Ruiting LI
;
Zhen LI
;
Ziguang XU
;
Zhulin GAO
;
Yina CHANG
;
Lingfei KONG
Author Information
1. 河南省人民医院 郑州大学人民医院 河南大学人民医院病理科，郑州 450003
- Keywords:
Soft tissue neoplasms;
Immunohistochemistry;
In situ hybridization;
Nodular fasciitis
- From:
Chinese Journal of Pathology
2022;51(6):524-529
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the clinicopathological, immunophenotypic and molecular genetic characteristics of nodular fasciitis (NF) in unusual sites.Methods:A total of 50 cases of NF diagnosed between January 2015 and January 2021 were reviewed in the Department of Pathology, Henan Provincial People′s Hospital, and the clinical and pathologic data were analyzed. Among them, 14 cases from unusual sites were included in this study. Immunohistochemical (IHC) staining was used to detect the expression of related proteins, and fluorescence in situ hybridization (FISH) was used to detect the breakage of the USP6 gene.Results:There were seven males and seven females in the 14 NF respectively. The lesions were located in the extremities, perineum, breast, wrist joints, the gap between lumbar vertebra 4/5, and in eight cases there was involvement of unusual tissues (six cases in skeletal muscle, one case in nerve root, and one case was intravascular). The tumor boundary was unclear with infiltrating growth. Spindle-shaped myofibroblasts were arranged in bundles or chaotically, with mild pleomorphic, small nucleoli and various mitotic figures. The tumor stroma showed collagenization to myxoid degeneration with erythrocyte extravasation and infiltration of inflammatory cells. IHC staining showed that the spindle cells expressed SMA focally or partially, and p16 diffusely and strongly. FISH showed that 12 of 14 cases had USP6 gene breakage, and two of them occurred in the intrathoracic skeletal muscle with the red signal amplification of USP6 gene.Conclusions:NF in unusual sites shows similar clinicopathological and genetic characteristics to classic NF, but the tumor mostly has infiltrating borders, non-specific and strong expression of p16, and USP6 red signal amplification. The pathological diagnosis of NF in rare sites should be highly vigilant.
