The clinical value of serum concentrations of cancer antigen 125 in patients with primary fallopian tube carcinoma: a multicenter study.

BACKGROUND: Primary fallopian tube carcinoma (PFTC) is a rare disease, and data on the serum concentration of tumor marker cancer antigen 125 (CA 125) in patients with this disease are sparse. The authors assessed the clinical value of the serum concentration of CA 125 as a prognostic and monitoring marker in patients with surgically treated PFTC.

METHODS: In a multicenter study, the concentration of CA 125 was measured in 406 serum samples from 53 patients with PFTC. The results were correlated with clinical data.

RESULTS: The pretreatment median serum CA 125 level was 183 U/mL (range, 6.5-5440.0 U/mL) in patients with PFTC. In a univariate Cox regression model, tumor stage and serum CA 125 level were associated significantly with shortened disease free survival (P = 0.006 and P < 0.001, respectively) and with overall survival (P = 0.03 and P = 0. 001, respectively). Lymph node involvement, tumor grade, and patient age were not associated with the length of survival. A multivariate Cox regression model showed that pretreatment the serum CA 125 level was a prognostic factor of disease free and overall survival, independent of tumor stage (P = 0.005 and P = 0.01, respectively). The pretreatment serum CA 125 level was correlated with tumor stage (P < 0.001) but not with lymph node involvement (P = 0.8), histologic grade (P = 0.3), or patient age (P = 0.2). The serum CA 125 level during chemotherapy was correlated significantly with Gynecologic Oncology Group response criteria to chemotherapy (P = 0. 001). During the follow-up of patients, serum CA 125 levels reached sensitivity, specificity, positive predictive value, and negative predictive value of 92%, 90%, 67%, and 98%, respectively, for differentiating between no evidence of disease and the presence of recurrent disease. In 90% of the patients, an increase of serum CA 125 level preceded the clinical or radiologic diagnosis of recurrent disease with a median lead time of 3 months (range, 0.5-7.0 months).

CONCLUSIONS: This is the largest study to date with respect to serum CA 125 levels in patients with PFTC. The current data indicate that the pretreatment serum CA 125 level is an additional independent prognostic factor of disease free and overall survival in patients with PFTC. The serum CA 125 level adequately defines the response to chemotherapy and displays good sensitivity and specificity characteristics during the follow-up of patients with PFTC.