LAPTM4B overexpression is a novel independent prognostic marker for metastatic ovarian tumors.

OBJECTIVE: Metastatic ovarian tumors are a series of lethal carcinomas that almost always have bad prognosis. Their prognoses, however, vary depending on the primary tumor malignancies of each. It has been reported that LAPTM4B, a novel tumor-associated gene, might indicate a worse prognosis when it was overexpressed in other carcinomas. Therefore, the authors expected to investigate whether LAPTM4B overexpression is an independent prognostic marker in metastatic ovarian tumors.

METHODS: Immunohistochemistry was used to assess LAPTM4B expression in metastatic ovarian tumors from 102 patients. Subsequently, univariate and multivariate survival analyses with Cox regression were performed to determine the association between LAPTM4B expression and prognosis. To identify any differences in prognosis between the 2 groups of patients with differing primary malignancies, the log-rank test was used.

RESULTS: The median overall and progression-free survival rates of patients with tumors of gastrointestinal tract origin were 0.97 and 0.51 years, respectively, and both were statistically significantly lower than those of patients with tumors of breast origin (P < 0.0001), which were 2.68 and 1.96 years, accordingly. Of 102 patients, 77 were classified as having a high expression of LAPTM4B, and LAPTM4B expression had a significant association with the prognosis of metastatic ovarian tumors (P < 0.01); no statistically significant interaction between LAPTM4B expression and primary malignancies was detected (P > 0.1). On the other hand, medians of overall survival and progression-free survival of patients with tumors of gastrointestinal tract origin were significantly lower than those of patients with tumors of breast origin (P < 0.0001).

CONCLUSIONS: Patients with metastatic ovarian tumors of breast origin had significantly better prognosis than those with the disease from gastrointestinal tract primary malignancies. LAPTM4B overexpression might be an independent prognostic marker of metastatic ovarian tumors.