Pregnancy and glial brain tumors.

Background: Improvements in brain tumor treatments have led to an increase in the number of young women with brain tumors who are now considering pregnancy. The aim of this study is to evaluate the influence of pregnancy on brain tumor biology.

Methods: In this institutional review board-approved retrospective study, we searched the institution's database for patients with glial brain tumors who were pregnant at the time of diagnosis or became pregnant during the course of their illness. We identified 34 such patients and reviewed their charts to determine each patient's clinical course and pregnancy outcome.

Results: Fifteen patients were diagnosed with a primary brain tumor during pregnancy: 3 with glioblastomas, 6 with grade III gliomas, and 6 with grade II gliomas. Pregnancy was terminated in only 2 of these patients, and the remainder delivered healthy babies. Twenty-three patients became pregnant after diagnosis (4 patients were pregnant at diagnosis and again after diagnosis). Of the patients who became pregnant after diagnosis, the 5 with grade I tumors had stable disease during and after pregnancy. However, of the 18 patients with grade II or III gliomas, 8 (44%) had confirmed tumor progression during pregnancy or within 8 weeks of delivery.

Conclusions: In contrast to grade I gliomas, the tumor biology of grades II and III gliomas may be altered during pregnancy, leading to an increased risk of tumor progression. These findings support the need for increased tumor surveillance and patient counseling and for additional data collection to further refine these results.