Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX.
Department of Dermatology, Baylor College of Medicine, Houston, TX; and.
Am J Dermatopathol. 2024 May 1;46(5):309-311. doi: 10.1097/DAD.0000000000002694.
A collision tumor is an infrequent phenomenon characterized by the presence of 2 histologically distinct tumor types (either benign or malignant) occurring within the same specific anatomical site. We describe a rare case of co-occurrence of basal cell carcinoma and atypical fibroxanthoma presenting as a single lesion on the scalp in a 76-year-old man. The lesion was clinically suspicious for basal cell carcinoma and biopsied. Histologic examination showed 2 distinct tumors, one with basaloid cells and the other one with pleomorphic spindle cells colliding and growing together. Immunohistochemical stains were crucial in establishing the diagnosis. This presentation is exceedingly rare and requires additional evaluation for diagnosis.
碰撞瘤是一种罕见的现象，其特征是在同一特定解剖部位同时存在 2 种组织学上明显不同的肿瘤类型（良性或恶性）。我们描述了 1 例罕见的基底细胞癌和非典型纤维黄色瘤同时发生的病例，表现为 1 例 76 岁男性头皮单发病变。病变临床上疑似基底细胞癌并进行了活检。组织学检查显示 2 个截然不同的肿瘤，1 个肿瘤具有基底样细胞，另 1 个肿瘤具有多形性梭形细胞碰撞并一起生长。免疫组织化学染色在确立诊断方面至关重要。这种表现极其罕见，需要进一步评估以明确诊断。
