Melanoma in an Unlikely Guise: Diagnostic Challenges of a Solid–cystic Popliteal Mass in Neurofibromatosis Type 1
- 1Department of Radiodiagnosis, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (DPU), Pimpri-Chinchwad, Maharashtra, India
- 2Department of Pathology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (DPU), Pimpri-Chinchwad, Maharashtra, India
Abstract
Malignant melanoma (MM) uncommonly presents as a solid–cystic soft tissue mass, posing a significant diagnostic challenge. We report a rare case in a 63-year-old woman with neurofibromatosis type 1 (NF-1) who presented with a painful, rapidly progressive swelling on the posterior aspect of her right lower thigh. Imaging revealed a large, well-defined solid–cystic lesion suggestive of a soft tissue sarcoma or malignant peripheral nerve sheath tumor. Initial fine-needle aspiration cytology was nondiagnostic. Definitive diagnosis was achieved following wide surgical excision, with histopathological and immunohistochemical analysis confirming MM (strongly positive for S100, Melan-A, and SOX10). This case highlights that MM must be considered in the differential diagnosis of atypical cystic soft tissue lesions, even in anatomically unexpected locations, especially in patients with predisposing conditions such as NF-1 and affirms the indispensable integration of multimodality imaging with histopathological and immunohistochemical correlation in resolving diagnostically challenging soft tissue masses.
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BibTeX
@article{pandey2026melanoma,
title = {{Melanoma in an Unlikely Guise: Diagnostic Challenges of a Solid–cystic Popliteal Mass in Neurofibromatosis Type 1}},
author = {Ankita Arvind Pandey and Richa Mariam Roy and Purnachandra Lamghare and Archana Buch},
journal = {Annals of African Medicine},
year = {2026},
month = jun,
doi = {10.4103/aam.aam_289_26},
url = {https://doi.org/10.4103/aam.aam_289_26},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - JOUR
TI - Melanoma in an Unlikely Guise: Diagnostic Challenges of a Solid–cystic Popliteal Mass in Neurofibromatosis Type 1
AU - Ankita Arvind Pandey
AU - Richa Mariam Roy
AU - Purnachandra Lamghare
AU - Archana Buch
PY - 2026
DA - 2026/06/09
JO - Annals of African Medicine
DO - 10.4103/aam.aam_289_26
UR - https://doi.org/10.4103/aam.aam_289_26
AB - Malignant melanoma (MM) uncommonly presents as a solid–cystic soft tissue mass, posing a significant diagnostic challenge. We report a rare case in a 63-year-old woman with neurofibromatosis type 1 (NF-1) who presented with a painful, rapidly progressive swelling on the posterior aspect of her right lower thigh. Imaging revealed a large, well-defined solid–cystic lesion suggestive of a soft tissue sarcoma or malignant peripheral nerve sheath tumor. Initial fine-needle aspiration cytology was nondiagnostic. Definitive diagnosis was achieved following wide surgical excision, with histopathological and immunohistochemical analysis confirming MM (strongly positive for S100, Melan-A, and SOX10). This case highlights that MM must be considered in the differential diagnosis of atypical cystic soft tissue lesions, even in anatomically unexpected locations, especially in patients with predisposing conditions such as NF-1 and affirms the indispensable integration of multimodality imaging with histopathological and immunohistochemical correlation in resolving diagnostically challenging soft tissue masses.
SN - 1596-3519
SN - 0975-5764
ER -