背景:猫注射部位纤维肉瘤是在慢性炎症背景下出现的侵袭性和浸润性肿瘤。这项研究的目的是评估猫注射部位纤维肉瘤中金属硫蛋白(I-II)的表达,并评估其与Ki67指数的可能关系。炎症评分和肿瘤分级。这项研究包括40个猫纤维肉瘤,位于常见的注射部位(即,肩胛骨间区,大腿,侧翼),构成2019-2020年间收集的档案诊断标本。根据新提出的猫软组织肉瘤分级系统对肿瘤进行组织学分级。进行免疫组织化学以评估Ki67和金属硫蛋白在肿瘤细胞中的表达。
结果:在所有I级肿瘤中均观察到金属硫蛋白的细胞质和有时核表达,66.67%的II级肿瘤和55%的III级肿瘤。金属硫蛋白的表达与肿瘤分级、炎症评分呈负相关,而Ki67指数与肿瘤分级呈正相关,炎症评分和坏死评分。
结论:猫注射部位纤维肉瘤中MT表达的下调似乎与炎症浸润的增加有关,因此肿瘤进展。这是描述猫注射部位纤维肉瘤中金属硫蛋白表达的第一项研究。
BACKGROUND: Feline injection site fibrosarcoma is an aggressive and infiltrative tumour arising in the background of chronic inflammation. The aim of this study was to evaluate the expression of metallothionein (I-II) in feline injection site fibrosarcomas and to assess its possible relationships with Ki67 index, inflammation score and tumour grade. The study included 40 feline fibrosarcomas, located in the common injection sites (i.e., interscapular area, thigh, flank), constituting archival diagnostic specimens collected between 2019-2020. Tumours were graded histologically according to the newly proposed soft-tissue sarcoma grading system in cats. Immunohistochemistry was performed to evaluate the expression of Ki67 and metallothionein in tumour cells.
RESULTS: The cytoplasmic and sometimes nuclear expression of metallothionein was observed in all tumours grade I, 66.67% of tumours grade II and 55% of tumours grade III. The expression of metallothionein was negatively correlated with tumour grade and inflammation score, while the Ki67 index was positively correlated with tumour grade, inflammation score and necrosis score.
CONCLUSIONS: The downregulation of MT expression in feline injection site fibrosarcomas seems to be connected with an increase in the inflammatory infiltration, hence tumour progression. This is the first study describing metallothionein expression in feline injection site fibrosarcomas.