Metastatic acral melanoma with retroperitoneal and liver metastases: Diagnostic challenges and therapeutic dilemmas in a resource-limited clinical setting of district Swat, Pakistan

Acral melanoma is a rare subtype of cutaneous melanoma that often presents late in resource-limited settings. We report a 67-year-old woman from District Swat, Pakistan, with a 5-year history of a neglected pigmented plantar lesion who presented with jaundice and weight loss. CT imaging showed a large para-aortic retroperitoneal mass causing hydronephrosis and periampullary compression with biliary dilatation, along with liver metastases. Trucut biopsy revealed metastatic melanoma (S100+, HMB-45+, SOX10+). Molecular testing for BRAF V600 mutation was recommended but not performed due to unaffordability. Nivolumab monotherapy (anti–programmed cell death protein 1 [anti–PD-1]) was started, as dual immune checkpoint blockade was unaffordable, and a ureteric stent was placed. The patient was subsequently lost to follow-up. This case highlights diagnostic complexity and therapeutic inequities in metastatic acral melanoma in a resource-limited setting.