LAUSR

OBJECTIVE To compare the efficacy of ascitic fluid cell block (ACB) with that of core needle biopsy (CNB) or the CA125/CEA ratio in diagnosing primary tubo-ovarian cancer in female patients with peritoneal carcinomatosis (PC) with ascites. METHODS This retrospective study examined female patients with PC with ascites who had available results for ACB, peritoneal tumor CNB, and the CA125/CEA ratio. Several measures of the accuracy of ACB and the CA125/CEA ratio were calculated and compared, with CNB as the reference standard. RESULTS Of 81 patients with available results, 57 were clinically diagnosed with primary tubo-ovarian cancer. Overall, 52, 47, and 64 patients were diagnosed via CNB, ACB, and CA125/CEA ratio > 25, respectively. CNB and ACB identified the cancer origin in 91.4% and 82.7% cases, respectively. The concordance ratio of the immunohistochemical findings between ACB and CNB was 93.6%. Two patients with inconclusive CNB results were diagnosed with primary tubo-ovarian cancer via ACB. The sensitivity, specificity, positive predictive value, negative predictive value, and positive likelihood ratio were 86.5%, 93.1%, 95.7%, 79.4%, and 12.5, respectively, for ACB and 94.2%, 48.3%, 76.6%, 82.4%, and 1.82, respectively, for CA125/CEA ratio > 25. CONCLUSIONS ACB is not inferior to CNB in diagnosing primary tubo-ovarian cancer; the two methods complement each other. ACB can substitute CNB in diagnosing primary tubo-ovarian cancer in selected PC patients. ACB is superior to a CA125/CEA ratio of >25 in diagnosing primary tubo-ovarian cancer. ACB is effective, reliable, and convenient for diagnosing primary tubo-ovarian cancer in PC patients with ascites.