Hrudka Jan, Charvát Martin, Grossmann Petr, Kinkor Zdeněk
Cesk Patol. 2020 Spring;56(2):89-93.
Dermatofibrosarcoma protuberans is a quite rare local aggressive tumor of dermis and subcutis, revealing characteristic morphology and chromosomal translocation (17; 22)(q21;q13) with gene fusion COL1A1-PDGFB. The tumour almost never metastasizes and complete excision signs an excellent prognosis. Approximately in 10% of cases, dermatofibrosarcoma undergoes a fibrosarcomatous transformation associated with metastatic disease and worse prognosis. In this paper, we refer a case of a male patient with subcutaneous tumor in back region, in which the small biopsy lead to diagnosis of a spindle cell sarcoma. However, only the histopathological examination of the entire tumor in the material from the radical surgery detected the dermatofibrosarcoma protuberans with fibrosarcomatous transformation. Both components of the tumor showed the characteristic genetic alteration. Identification of fibrosarcomatous component within the DFSP matters in prognosis. Distinction between fibrosarcoma arising within the dermatofibrosarcoma protuberans and fibrosarcoma arising de novo is of therapeutic consequence: the patients with metastatic or inoperable DFSP with fibrosarcomatous transformation may profit form imatinib treatment.
隆突性皮肤纤维肉瘤是一种相当罕见的真皮和皮下组织局部侵袭性肿瘤，具有特征性形态和染色体易位（17；22）（q21；q13）以及基因融合COL1A1 - PDGFB。该肿瘤几乎从不发生转移，完整切除后预后良好。大约10%的病例中，隆突性皮肤纤维肉瘤会发生纤维肉瘤样转化，伴有转移性疾病且预后较差。在本文中，我们报告了一例背部皮下肿瘤的男性患者，小活检诊断为梭形细胞肉瘤。然而，只有对根治性手术标本中整个肿瘤进行组织病理学检查才检测出伴有纤维肉瘤样转化的隆突性皮肤纤维肉瘤。肿瘤的两个成分均显示出特征性基因改变。在隆突性皮肤纤维肉瘤中识别纤维肉瘤样成分对预后很重要。区分隆突性皮肤纤维肉瘤内发生的纤维肉瘤和原发性纤维肉瘤具有治疗意义：发生纤维肉瘤样转化的转移性或无法手术切除的隆突性皮肤纤维肉瘤患者可能从伊马替尼治疗中获益。
