误诊为黑色素瘤的视网膜色素上皮细胞来源的腺癌1例(英文)

Adenocarcinoma of retinal pigmented epithelium clinically diagnosed as malignant melanoma:a case report with short review of literature

视网膜色素上皮细胞(RPE)形成的肿瘤较少,常见肿瘤类型有黑色素瘤,少见类型包括RPE形成的腺癌,这两种肿瘤在临床和病理特点上都有所不同。本文报道1例60岁的男性患者,因为进展性视力丧失,眼科诊断为黑色素瘤而行右眼摘除术。病理学检查发现后极部接近视神经处可见实性、界限清楚的病灶。组织学检查见构成肿瘤的细胞,具有大的多形、浓染的核,核仁突出,色素极少;肿瘤细胞多呈乳头状排列。为和黑色素瘤进行区别,进一步行免疫组织化学染色。结果显示上皮膜抗原(EMA)为强阳性,HMB45阴性,支持RPE来源的腺癌诊断。系统检查排除了转移癌。总之,虽然RPE来源的腺癌非常少见,但必须清楚它与脉络膜黑色素瘤在诊断上的异同点。

True neoplasm of retinal pigmented epithelium（RPE） is rare,but because of important differential diagnosis including malignant melanoma（which is more common than adenocarcinoma of RPE） ,both in clinical and pathological characteristics,we are interested in reporting this case.A 60-year-old man underwent right eye enucleation because of progressive loss of vision and ophthalmologic diagnosis of malignant melanoma.Pathological findings revealed a lesion in posterior segment near the optic nerve.The mass was solid and well circumscribed.In histological evaluation,the tumor was composed of cells having large,pleomorphic and hyperchromatic nuclei,prominent nucleoli and occasional pigmentation.Tumor cells were mostly arranged in papillary pattern.For differentiation of melanoma,immuno-histochemistry was done.Epithelial membrane antigen（EMA） was strongly positive and HMB45 was negative;consistent with the diagnosis of adenocarcinoma of RPE.Systemic evaluation ruled out any metastasis.In conclusion,although adenocarcinoma of RPE is rare,but must be kept in mind in differential diagnosis of malignant melanoma of choroids.