Peritoneal metastases in children with cancer.

BACKGROUND: This study attempted to evaluate the childhood malignancies associated with computed tomography (CT) detected peritoneal metastases as well as the diagnostic imaging characteristics of these metastases as shown on CT.

METHODS: The authors reviewed all available pathology specimens and abdominopelvic CT scans of patients identified as having peritoneal metastases at three childhood cancer centers. Patient demographics, primary diagnosis, and CT characteristics of such metastases were evaluated.

RESULTS: Peritoneal metastases were identified by CT in 32 children with cancer either at diagnosis (n = 20) or up to 6.2 years from diagnosis (n = 12). On CT, peritoneal disease appeared as a mass in 26 cases, as studding in 11 cases, as peritoneal enhancement in 15 cases, and as diffuse caking in 4 cases (15 patients had > 1 category of peritoneal metastasis). Thirteen patients had concurrent metastases in other sites. Fourteen patients died of progressive disease at a median of 10 months from the time peritoneal metastases were identified on CT. At last follow-up, the remaining 18 patients were alive, with follow-up ranging from 1 month to 9.7 years. As expected, peritoneal metastases were identified in patients with germ cell tumors and colon carcinoma. However, they also were observed in patients with epithelioid carcinoma, leiomyosarcoma, pineoblastoma, neuroblastoma, melanoma, and peripheral neuroectodermal tumor.

CONCLUSIONS: Peritoneal metastases have variable appearance on CT, but most commonly appear mass-like. They are associated with a wider range of primary diagnoses than reported previously. The outcome varies with the type of the primary tumor and its responsiveness to existing therapies.