Metastatic colorectal carcinoma: an unusual presentation.

Cutaneous metastases from colorectal carcinomas occur infrequently, usually in the setting of disseminated disease. They most commonly appear on the abdominal wall or perineal area; metastases to other locations of the skin are rare. We describe a case of colorectal signet ring carcinoma with metastasis to the upper lip. To the authors' knowledge, this is the second reported case of colorectal carcinoma with metastasis to the lip and first with signet ring features. Because of the rarity of cutaneous metastases, the primary physician or pathologist may overlook this diagnosis. However, this entity should be considered in the differential diagnosis of adnexal tumors as it may be the initial presentation of the colon carcinoma.