Solitary Gluteal Subcutaneous Metastasis after Curative Resection of Cecal Cancer: A Rare Presentation Preceding Systemic Metastasis

INTRODUCTION: Cutaneous and subcutaneous colon cancer metastases to the gluteal or perineal regions are extremely rare. Unlike the local recurrence or tumor implantation observed in rectal cancer, gluteal or perineal colon cancer metastasis likely represents a distinct pathophysiological mechanism. We report a case of a solitary subcutaneous gluteal metastasis that developed after curative resection of cecal cancer. CASE PRESENTATION: A 58-year-old woman underwent laparoscopic ileocecal resection with D3 lymph node dissection for a stage IIIC cecal adenocarcinoma. Postoperative adjuvant chemotherapy with capecitabine and oxaliplatin (CAPOX) was administered for 4 cycles but discontinued owing to hepatic dysfunction. Nine months postoperatively, the tumor marker levels increased; imaging revealed a subcutaneous mass in the left gluteal region. The gluteal mass was completely resected with clear margins. The histopathological findings were consistent with metastasis from the previously resected cecal carcinoma. Adjuvant CAPOX was resumed for 4 additional cycles. Nine months after reoperation, the patient developed a solitary brain metastasis, which was surgically removed, followed by radiotherapy. Subsequently, systemic chemotherapy was initiated, and the patient remains alive without evidence of recurrence 5 months after resection of the brain metastasis. CONCLUSIONS: Gluteal or perineal subcutaneous metastases from colon cancer are rare and may represent an early manifestation of systemic disease rather than an isolated metastatic event. Even after curative resection, careful postoperative surveillance is warranted.