RESUMO
Skin metastases, as a presenting symptom of gastrointestinal malignancies, are very rare and signify aggressive disease. They usually occur after a long period of diagnosis and along with other visceral metastases. We present the case of an 18-year-old male with diffuse subcutaneous metastases as a presenting feature and as the only site of distant metastases due to rectosigmoid adenocarcinoma. They clinically mimic benign skin lesions and the patient might not present to an oncologist. The diagnosis has to be established by skin biopsy, which will show tumor cell infiltration of the epidermis, dermis, and/or subcutaneous fat. There is no established local treatment for diffuse lesions. Systemic chemotherapy indicated for metastatic colon carcinoma was employed with not much favorable response. Irinotecan based chemotherapy also resulted in posterior reversible encephalopathy syndrome in this patient. Overall, the disease carries a poor prognosis and with no effective treatment available the survival is less than a year.
