Osama Md Ali, Rao Seema, Bakshi Neha, Badwal Sonia, Aggarwal Shyam
Department of Pathology, Lady Hardinge Medical College, New Delhi, India.
Department of Histopathology, Sir Gangaram Hospital, New Delhi, India.
J Lab Physicians. 2022 Oct 20;15(2):300-305. doi: 10.1055/s-0042-1757236. eCollection 2023 Jun.
Malignant melanoma is an aggressive, notorious tumor showing great variability in morphological and immunohistochemical expression, thus commonly leading to an erroneous diagnosis. Within the melanoma group, amelanotic melanoma, with its wide clinical presentations, lack of pigmentation, and varied histological appearances, has taken on a new persona as a master masquerader. Use of immunohistochemistry in the diagnosis of malignant tumors, including melanoma, is primordial and indispensable. However, the problem gets compounded in scenario of aberrant antigenic expression. The present case posed multiple diagnostic challenges in form of atypical clinical presentation, variant morphology, as well as aberrant antigenic expression. Here, we present the case of a 72-year-old male who, upon his initial presentation, was thought to be sarcomatoid anaplastic plasmacytoma, but 5 months later another biopsy from a different site revealed the actual diagnosis of amelanotic melanoma.
恶性黑色素瘤是一种侵袭性强、声名狼藉的肿瘤，在形态学和免疫组化表达上表现出极大的变异性，因此常导致误诊。在黑色素瘤群体中，无色素性黑色素瘤临床表现多样、缺乏色素沉着且组织学表现各异，已成为一种新的主要伪装者。免疫组化在包括黑色素瘤在内的恶性肿瘤诊断中至关重要且不可或缺。然而，在抗原表达异常的情况下，问题会变得更加复杂。本病例在非典型临床表现、形态变异以及抗原表达异常等方面带来了多重诊断挑战。在此，我们报告一例72岁男性患者，其初诊时被认为是肉瘤样间变性浆细胞瘤，但5个月后来自不同部位的另一活检显示实际诊断为无色素性黑色素瘤。
