小细胞恶性黑色素瘤10例临床病理分析

目的分析小细胞恶性黑色素瘤(SCMM)的临床病理特点、形态变化、免疫组化表达及鉴别诊断。方法应用HE染色、免疫组化SP法标记,对10例SCMM的形态学和临床资料进行分析。结果10例患者中男性6例,女性4例,年龄32~78岁,平均48.5岁。好发部位为足、手及躯干部皮肤。SCMM瘤细胞体积小,胞质极少,巢状、弥散片状或梁状分布,多数瘤组织中含有黑色素,少数无色素,瘤细胞核深染、核异型及有不明显核仁。10例SCMM均显示HMB 45、S-100及vimentin强( )。结论SCMM易被误诊为小细胞癌、Merkel细胞癌、非霍奇金恶性淋巴瘤、PNET、骨外尤文瘤或其他小细胞恶性肿瘤,无色素者更易被误诊。HMB 45、S-100v、imentin标记阳性有助诊断。

Small cell malignant melanoma: a clinicopathological study of 10 cases

Objective To study the clinicopathologic features,histopathologic variants,immunohistochemical staning and differential diagnosis in small cell malignant melanoma(SCMM). Methods Pathological changes of 10 cases of SCMM were studied with H-E staining and immunohistochemical techinque(S-P method) and their clinical data were analyzed. Results Of the 10 cases,6 were male and 4 female,the age of the patients ranged from 32 to 78 years(mean,48.5 years).The feet,hand and trunk were the most common location.The cells were small in size and scanty cytoplasm,usually in tighly packed nests,dispersed sheet and trabecular.Melanin pigment could be observed in the majority of SCMM,but sometimes amelanotic pigment was present.The cells contained hyperchromatic nuclei, subtle nuclear atypia and inconspicuous nucleoli.Immunohistochemically,the tumor cells were positive for HMB45,S-100 protein and vimentin in SCMM of all 10 cases. Conclusion SCMM may mimic small cell carcinoma,Merkel cell carcinoma,non-Hodgkin's lymphoma,PNET,extraskeletal Ewing's sarcoma or other small cell maliganant tumors,and amelanotic one can be misdiagnozed easily.It should be paid more attention to the differential diagnosis.HMB45,S-100,vimentin immunostaining is heipful to the diagnosis.