Extrapulmonary small cell cancer of the retroperitoneum

Small cell cancer is common in the lung, but may also be found in extrapulmonary sites, given the widespread distribution of the APUD cell, from which this tumor originates. We believe this is the first report of a small cell cancer in the retroperitoneum. An initial good response of the tumor to chemotherapy was followed six months later by appearance of metastases and patient's death. This clinical behavior is usual in extrapulmonary small cell cancer.