The purpose of this study was to determine whether LAPTM4B over‐expression is associated with the prognosis and chemotherapy resistance in patients with stages III and IV epithelial ovarian carcinoma, i.e., patients with peritoneal metastasis or lymph node metastasis of epithelial ovarian carcinoma.

LAPTM4B expression was evaluated in 10 normal ovarian and 113 stages III–IV ovarian carcinomas specimens by Western blotting analyses and immunohistochemistry. Univariate and multivariate analyses were performed to determine the association between LAPTM4B expression and prognosis and the relationship between LAPTM4B over‐expression and chemotherapy resistance.

Western blotting analysis demonstrated that LAPTM4B was overexpressed in ovarian cancers, and immunohistochemistry results revealed that 80 patients were LAPTM4B over‐expression. The five‐year overall survival (OS) rates for patients with high LAPTM4B expression and low LAPTM4B expression were 27.36% and 90.7%, respectively (hazard ratio = 20.611, 95% CI: 5.916–71.808, P < 0.0001). The five‐year progression‐free survival (PFS) rate was 17.68% for patients in the high‐expression group and 84.42% for patients in the low‐expression group (hazard ratio = 17.852, 95% CI: 6.31–5.935, P < 0.0001); The presence of chemotherapy resistance was significantly associated with LAPTM4B expression (OR: 36.609, 95% CI: 4.737–282.941, P = 0.0006).

LAPTM4B over‐expression is an independent factor in stages III–IV epithelial ovarian carcinoma prognosis and chemotherapy resistance, and it may be an important potential biomarker. J. Surg. Oncol. 2011;104:29–36. © 2011 Wiley‐Liss, Inc.