[Cutaneous metastases from adenocarcinoma of unknown primary site]

Metastatic cancer of unknown primary site appears in 5-10% of oncologic patients. The primary tumor is usually discovered at autopsy and only in 27% of patients alive. Metastases from cancer of unknown primary site may be located in the skin and subcutaneous tissue and it is the dermatologist the first in evaluating these patients. We present a case of cutanoeus metastases from moderately-differentiated adenocarcinoma of unknown primary site. The immunohistochemical study revealed positive staining for CEA and negative staining for PSA. The primary tumor could not be identified in spite of the imaging and endoscopic studies performed. Based on these studies we excluded a colorectal or prostatic origin and considered a pancreatic adencarcinoma as the possible primary tumor. Even though a minority of these patients will have a curable disease, the appropriate use of pathological diagnosis and selected imaging studies for an optimal management of patients with a tumor of unknown primary site should not be ignored.