Preoperative tumor marker elevations in lymph node positive appendiceal mucinous neoplasms with peritoneal metastases

The prognostic implications of elevated preoperative tumor markers in lymph node positive appendiceal mucinous neoplasm patients treated for peritoneal metastases (PM) has not been well defined.

Clinical features in addition to preoperative tumor markers were recorded within 1 week prior to cytoreductive surgery (CRS). Impact on overall survival of these factors was analyzed by univariate and multivariate analysis.

Thirty-nine patients were available for study of clinical features and 28 patients for study of tumor markers. The median age was 44 (range 26-65) and there were 13 (33 %) males. In univariate analysis, young age (HR 2.4, p = 0.0256), peritoneal cancer index 0-15 (HR 2.0, p = 0.0765), response to neoadjuvant chemotherapy (HR 4.8, p = 0.323), carcinoembryonic antigen (CEA) elevation >5.0 (HR 4.3, p = 0.0040), triple tumor marker elevation (HR 3.9, p = 0.0372), CEA elevated ×3 to ×10 (HR 3.9, p = 0.0515) and CEA elevated > ×10 (HR 6.6, p = 0.0037) were significant. By multivariate modeling, CEA elevation ≥5.0 stands out strongly and all other significant clinical and tumor marker variables were eliminated (HR 4.3, p = 0.0040).

Preoperative CEA elevation >5 in 13 patients showed a median survival of 3 years as compared to 15 patients (53.6 %) with non-elevated CEA with a median survival of 16 years. Preoperative CEA measurement may signal an aberrant tumor biology that indicates patients at high risk of treatment failure for CRS and HIPEC.