CC BY-NC-ND 4.0 · J Lab Physicians 2023; 15(02): 300-305
DOI: 10.1055/s-0042-1757236
Case Report

Amelanotic Melanoma: A Great Masquerader

1   Department of Pathology, Lady Hardinge Medical College, New Delhi, India
2   Department of Histopathology, Sir Gangaram Hospital, New Delhi, India
Neha Bakshi
2   Department of Histopathology, Sir Gangaram Hospital, New Delhi, India
Sonia Badwal
2   Department of Histopathology, Sir Gangaram Hospital, New Delhi, India
Shyam Aggarwal
3   Department of Medical Oncology and Bone Marrow Transplant, Sir Gangaram Hospital, New Delhi, India
› Author Affiliations
Funding None.


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.

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The authors certify that they have obtained the appropriate consent from the parent. The parent has given his consent for the images and other clinical information to be reported in the journal. The parent understands that the name and initials will not be published, and due efforts have been made to conceal the same.

Publication History

Article published online:
20 October 2022

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