Zhou X F, Yan Q G, Guo X J, Gou X D, Han J Q, Ye J L, Zhang H Y, Wang F M
Department of Pathology, the Affiliated Hospital of Qinghai University, Xining 810001, China.
Zhonghua Bing Li Xue Za Zhi. 2018 Jul 8;47(7):536-541. doi: 10.3760/cma.j.issn.0529-5807.2018.07.011.
To investigate the clinicopathologic features, immunophenotype, pathological diagnosis and treatment of malignant mixed tumor (MMT). Clinical and pathological features including immunohistochemical phenotypes were analyzed in a case of MMT accompanied with eccrine porocarcinoma (EP) involving both hands, diagnosed definitely in January 2018 along with review of relevant literature. A 64-year-old man presented with multiple rash on both hands for 4 years. Three lesions of 0.5 to 2.2 cm were removed for pathological evaluation. The pathological changes on little finger of left and right hands were MMT with EP, whereas that removed from the right ring finger was EP. MMT showed infiltrative growth with vascular wall invasion and consisted of epithelial (glandular or tube differentiation) and mesenchymal components (mucinous and/or cartilage stroma). The endothelial cells showed moderate to severe cytological atypia, nuclear pleomorphism and increased mitotic activity. The glandular component had histological characteristics of syringocarcinoma with moderately atypical chondrocytes but without myoepithelium. EP was composed of basal cells with visible vacuoles in cytoplasm and the presence of tubular and squamous differentiation, along with obvious atypia. Immunohistochemically cavosurface epithelium of glandular differentiation of MMT showed positivity for CK7, EMA and CD117. Myoepithelium showed S-100, CK5/6 and p63 positivity and stromal cells were positive for S-100. Differential diagnoses included metaplastic carcinoma, malignant myoepithelioma and atypical mixed tumor of skin. MMT with EP is extremely rare.The diagnosis of MMT depends on the morphologic features. Immunohistochemical staining is helpful for differential diagnosis. Surgical excision with safety margins is the treatment of choice. Complementary radiotherapy and/or chemotherapy is still controversial. The clinical course of MMT is deemed unpredictable and long-term follow-up is necessary.
探讨恶性混合瘤（MMT）的临床病理特征、免疫表型、病理诊断及治疗方法。对2018年1月确诊的1例双手累及的MMT伴小汗腺导管癌（EP）患者的临床及病理特征（包括免疫组化表型）进行分析，并复习相关文献。一名64岁男性双手出现多发皮疹4年。切除3个大小为0.5至2.2厘米的皮损进行病理评估。左手和右手小指的病理改变为MMT伴EP，而从右手无名指切除的皮损为EP。MMT呈浸润性生长，侵犯血管壁，由上皮成分（腺性或管状分化）和间叶成分（黏液性和/或软骨基质）组成。内皮细胞显示中度至重度细胞学异型性、核多形性和有丝分裂活性增加。腺性成分具有汗腺癌的组织学特征，伴有中度异型性软骨细胞，但无肌上皮。EP由细胞质可见空泡的基底细胞组成，存在管状和鳞状分化，且异型明显。免疫组化显示，MMT腺性分化的腔面上皮CK7、EMA和CD117呈阳性。肌上皮S-100、CK5/6和p63呈阳性，基质细胞S-100呈阳性。鉴别诊断包括化生性癌、恶性肌上皮瘤和皮肤非典型混合瘤。MMT伴EP极为罕见。MMT的诊断取决于形态学特征。免疫组化染色有助于鉴别诊断。手术切除并保证切缘阴性是首选治疗方法。辅助放疗和/或化疗仍存在争议。MMT的临床病程被认为不可预测，需要长期随访。
