DNA replication error is frequent in ovarian granulosa cell tumors.

DNA replication errors (RER) have been detected in epithelial ovarian cancers, as well as in other human tumor types. These observations suggest that this genetic defect is present in ovarian granulosa cell tumors, and that a DNA mismatch repair deficiency may be involved in their development and/or progression. We therefore assayed tissue samples from 29 patients with granulosa cell tumors for RER, using polymerase chain reaction (PCR) and 5 microsatellite markers. The RER were observed at greater than or equal to 1 loci in 15 (58%) of 26 informative cases. The incidence of RER was unrelated to the patient's age or the histologic subtype or clinical stage of the tumors. The RER, however, were observed in 57% (8/14) of the informative patients with stage IA disease. These findings suggest that a DNA mismatch repair deficiency may contribute to the pathogenesis of ovarian granulosa cell tumors, and that this deficiency may be an early event in their development and/or progression.