Pleural Metastases From Acral Lentiginous Melanoma Diagnosed by Medical Thoracoscopy

Acral lentiginous melanoma (ALM) with pleural metastases is rare and under-recognised. We report an 86-year-old woman with progressive dyspnoea and pleuritic chest pain. 18 months ago, she was diagnosed with stage IIC ALM of the right heel, and was treated with wide local excision, but she declined adjuvant therapy. Imaging demonstrated a large left pleural effusion with diffuse pleural thickening, pulmonary mass, and hepatic metastases. Brownish pleural fluid, along with thoracoscopic identification of multiple pigmented nodules, led to a histologically confirmed diagnosis. Talc pleurodesis was performed for symptom control, and best supportive care was pursued. This case highlights the diagnostic value of medical thoracoscopy in identifying pleural melanoma metastases and emphasises the need to consider melanoma recurrence when pigmented effusions are encountered.