Giant cutaneous melanoma presenting with hemorrhagic complications.

Giant cutaneous melanoma is a rare presentation characterized by significant morbidity and mortality. We report the case of a 45-year-old male presenting with an acute life-threatening hemorrhage from a giant melanoma on his right thigh. The tumor, measuring 90 × 50 × 85 mm, was immediately excised under local anesthesia to achieve hemostasis. The patient exhibited acute anemia and required postoperative blood transfusion. Histopathological analysis confirmed superficial spreading melanoma with a Breslow thickness of 85.0 mm and extensive ulceration. Genetic testing identified critical mutations, including BRAFV600D and alterations involving the ARID2, CDKN2A/B, AKT3, PTEN, and HRAS genes. Remarkably, no metastatic disease was detected upon thorough diagnostic evaluation. The patient received adjuvant immunotherapy with PD-1 inhibitors. Six months after the procedure, he remains free of metastasis. This case underscores the urgent need for timely recognition and intervention in giant melanoma with acute complications. It also highlights the effectiveness of modern adjuvant therapies in improving prognosis.