Safe fertility-preserving management in gynecological malignancies

Practical Prediction Model for Ovarian Insufficiency after Radiation

OBJECTIVE

 The present study aimed to develop a useful mathematical model that predicts the age at which premature ovarian insufficiency might occur after teletherapy radiation. A diagnosis of premature or early menopause has physical and psychological consequences, so women may need support and long-term medical follow-up.

METHODS

 To correlate ovarian radiation dose with ovarian function, we used the formula described by Wallace et al.: √g(z) = 10^(2-0,15z), where "g(z)" and "z" represent oocyte survival rate and the radiation dose (in Gray), respectively. By simulating different ages and doses, we observed a pattern that could be used to simplify the relationship between radiation dose and remaining time of ovarian function.

RESULTS

 We obtained a linear function between ovarian radiation dose and loss of ovarian function (LOF) that is the percentage of decrease in the time to the ovarian failure compared with the time expected for a woman at the same age without irradiation exposition. For patients < 40 years old and with ovarian radiation doses < 5 Gy, the equation LOF = 2.70 + (11.08 x Dose) can be applied to estimate the decrease in time to premature ovarian insufficiency.

CONCLUSION

 The present study reports a practicable theoretical method to estimate the loss of ovarian function. These findings can potentially improve the management and counseling of young women patients submitted to radiotherapy during their reproductive years.

Evaluation of microsatellite instability in women with epithelial ovarian cancer

The function of microsatellite instability (MSI) and the optimal panel of markers for epithelial ovarian cancer (EOC) are not well established. This study aimed to use the National Cancer Institute (NCI) markers BAT25, BAT26, D2S123, D5S346 and D17S250 to evaluate MSI in patients with ovarian serous cystadenocarcinoma, compared with ovarian serous cystadenoma and normal ovaries. A total of 37 patients were divided into three groups, as follows: cystadenocarcinoma (n=13), cystadenoma (n=10) and normal ovaries (n=14). DNA was extracted with TRIzol and quantified by spectrophotometry. MSI was evaluated by polymerase chain reaction (PCR), and classified as high (MSI-H), low (MSI-L) or stable (MSS). FIGO staging was I/II in 23.1% and III/IV in 76.9% of the cystadenocarcinoma group. Polymorphisms were found using at least one marker in 32 women, and were observed with D2S123 (83.7%), D17S250 (81.1%), D5S346 (72.9%), BAT25 (21.6%) and BAT26 (16.2%) markers. In the cystadenocarcinoma group, BAT25, BAT26, D2S123, D5S346 and D17S250 markers were positive in 30.8, 76.9, 53.8, 69.2 and 69.2% of patients, respectively. The same markers were positive in 30, 50, 40, 60 and 30% of the cystadenoma group, and 50, 71.4, 71.4, 64.3 and 63.3% in the normal ovary group, respectively. MSI-H was present in 84.6, 60 and 78.6% of the cystadenocarcinoma, cystadenoma and normal patients, respectively. MSI-L was detected in 0, 30 and 7.1%, and MSS was identified in 15.4, 10 and 14.3% of the cystadenocarcinoma, cystadenoma and normal patients, respectively. The frequency of MSI in both benign epithelial ovarian neoplasms and in normal ovaries was high, as well as in EOC, with no statistically significant difference between the groups. This suggests that MSI may arise as a consequence of the ovulatory process, and not solely as a feature of malignant ovarian tumors.