Cutaneous metastasis of ascending colon cancer harboring a BRAF V600E mutation: A rare case report

RATIONALE: Cutaneous metastases from colorectal cancer are extremely rare and generally appear several years after diagnosis or resection of the primary colorectal tumor. Although cutaneous metastasis is unusual, it often indicates a poor prognosis. PATIENT CONCERNS: We treated a 62-year-old woman with multiple cutaneous metastatic nodules on the chest, back, and armpit 7 months after resection of ascending colon cancer. DIAGNOSES: The patient was diagnosed with cutaneous metastasis of ascending colon cancer with BRAF V600E mutation. INTERVENTIONS: After 6 cycles of fluorouracil, leucovorin, oxaliplatin, cetuximab, and emurafenib, most of the metastatic lesions had begun to shrink, and no new metastases were observed. Serum tests showed that the levels of several tumor markers were decreased. OUTCOMES: The patient responded well to treatment and survived for 6.5 months after presentation with skin metastasis. LESSONS: Cutaneous metastasis of colorectal cancer with BRAF V600E mutation is a rare but important phenomenon that should not be ignored. Cutaneous metastasis of colorectal cancer frequently indicates advanced disease and poor prognosis. The SWOG 1406 program is one of the treatment options, but this needs further exploration.