29-year-old previously healthy man noticed a dark patch on his lower back since childhood, thought to be a benign congenital nevus. The lesion remained stable at about 2–3 cm for years, but began enlarging and ulcerating roughly a year before medical evaluation. Rapid growth occurred in the last two months.
He reported intermittent sharp pain from the site, fatigue, night sweats, fever, and an unexplained 30-pound weight loss over the past eight months. While he had no personal medical history of note, his paternal grandfather had metastatic melanoma.
On examination, he presented with a large foul-smelling mass on his lower back measuring 22 × 25 × 7 cm, with central necrosis (13 × 12.5 cm), and an enlarged left inguinal lymph node. CT imaging showed tumor invasion into subcutaneous tissue and a 15 cm metastatic lymph node. Small lung nodules were suspicious for metastases, but too small for biopsy. A biopsy of the primary tumor revealed a poorly differentiated high-grade malignant melanoma. The tumor was S-100 positive, MART-1 negative, and rarely HMB-45 positive. He was staged as having stage IV disease.
Palliative tumor removal was performed with a 4-cm margin. No gross extension beyond subcutaneous tissue was noted. The resected mass weighed 7280 grams and had a fibrino-purulent surface. The tumor varied in color and showed areas of hemorrhage and cystic degeneration. The wound was irrigated and treated with a vacuum-assisted closure, followed by skin grafting on day 7. The goal of surgery was to relieve symptoms and prevent severe infection.
Postoperative chemotherapy began with a 6-week course of temozolomide, which failed. A second regimen combining temozolomide and cisplatin also produced no response and the lymph node enlarged. A third regimen of paclitaxel, cisplatin, and temozolomide led to a marked response — the lymph node shrank from 15 cm to 6 cm after two treatment cycles.
