[Stereotactic radiosurgery for vestibular schwannoma: early and long-term radiation-induced changes and tumor growth control]

[Expression of estrogen and progesterone receptors in vestibular schwannomas]

INTRODUCTION

Stereotactic radiosurgery is one of the main treatments for vestibular schwannomas (VS). Their feature is frequent post-radiation pseudoprogression. This may be due to hormonal status of patients.

OBJECTIVE

To analyze expression of progesterone and estrogen receptors in women and men with VS.

MATERIAL AND METHODS

Immunohistochemical analysis of expression of progesterone (PR) and estrogen receptors (ER) after biopsy was performed in 240 patients with VS between 2018 and 2021. ER/PR expression was assessed in men (n=120) and women (n=120) in 3 age subgroups: young age (18-44 years), middle age (45-59 years) and old age (60-79 years). Each subgroup included 40 patients. Statistical analysis was performed using the Mann-Whitney test and MedCalc software.

RESULTS

ER expression is not typical for VS (men - 1 (0.01%), women - 3 (2.5%)). At the same time, PR expression was found in 29 (24.2%) men and 21 (17.5%) women. We found no significant difference in expression of ER and PR between men and women. However, variability in PR expression was revealed, i.e. predominance of this indicator in young women (p=0.0463) and middle-aged men (p=0.0110). Expression of PR was similar in elderly patients (p=0.2382).

CONCLUSION

The established incidence of PR expression may be one of the probable causes affecting development and duration of VS pseudoprogression after radiosurgery without clear relationship between sex and age. Further prospective research is needed to predict the risks of pseudoprogression.