Nguyen Catherine M, Cassarino David S
Department of Dermatology, University of Cincinnati, Cincinnati, Ohio.
Department of Pathology, Kaiser Permanente, Sunset Medical Center, Los Angeles, California.
J Cutan Pathol. 2017 Mar;44(3):292-295. doi: 10.1111/cup.12884. Epub 2017 Feb 2.
Benign cutaneous mixed tumor (chondroid syringoma) is the cutaneous counterpart of the benign mixed tumor (pleomorphic adenoma) of salivary glands, consisting of both epithelial and mesenchymal elements. The incidence of cutaneous mixed tumor is rare, composing <0.01% of all primary skin tumors. Herein, we report a case of malignant mixed tumor which recurred in the right thumb 20 years after the reported initial diagnosis of a benign mixed tumor at this site. Histologically, the lesion consisted of highly atypical and infiltrative cells in cords and ductal structures, with an adjacent focus of residual benign mixed tumor present. Perineural invasion of multiple dermal and subcutaneous nerves was also seen. Immunohistochemical staining was strongly and diffusely positive for CK5/6 and p63, with patchy positive S100 and CK7 staining. Wide excision was performed, with no evidence of recurrence or metastasis 5 years later.
良性皮肤混合瘤（软骨样汗管瘤）是涎腺良性混合瘤（多形性腺瘤）的皮肤对应物，由上皮和间充质成分组成。皮肤混合瘤的发病率很低，占所有原发性皮肤肿瘤的比例不到0.01%。在此，我们报告1例恶性混合瘤病例，该病例在最初诊断为该部位良性混合瘤20年后于右手拇指复发。组织学上，病变由条索状和导管结构中的高度非典型浸润性细胞组成，相邻部位可见残余的良性混合瘤灶。还可见多条真皮和皮下神经的神经周围侵犯。免疫组化染色显示CK5/6和p63呈强弥漫性阳性，S100和CK7染色呈斑片状阳性。进行了广泛切除，5年后无复发或转移迹象。
