Gender-specific growth dynamics of neurofibromatosis type-2-related tumors of the central nervous system

To date, few studies have been published about the growth dynamics of tumors associated with neurofibromatosis type-2 (NF2), none of which evaluated gender-specific differences. Our aim was to compare radiographic data of female and male patients with NF2.

MR images of 40 patients (20 female, 20 male) from the regional NF2 referral center were included in this analysis. Tumor sizes were determined by semi-automated volumetric measurement. Intracranial tumors were measured on post-contrast T1-weighted MRI datasets and volumes of intramedullary spinal tumors were determined from sagittal T2-weighted MRI datasets.

The median follow-up time was 91 months (range, 16–199 months) per patient. Intracranial tumors: On average, female patients had 13.4 neoplasms, while male patients had 6.75 (p = 0.042). The overall median time to tumor progression of ≥20 % was 20 months for females and 18 months for males. Tumors of the cerebellopontine angle (CPA) that had undergone previous surgery had shorter progression-free intervals in females than in males (16 and 24 months, respectively; p = 0.012). The median 1-year growth rate was 17.5 ± 44.6 % in females compared to 12.5 ± 44.9 % in males (p = 0.625). Intramedullary spinal tumors: On average, females had 2.05 tumors and males had 1.75 tumors (p = 0.721). Median time to tumor progression was 21 months in females and 44 months in males (p = 0.204). After 2 years, the median growth rate was 24.4 ± 56.8 % in female and 13.5 ± 40.4 % in male patients (p = 0.813).

The radiographic data in this study suggest that female patients are affected by a greater number of tumors than male patients and that post-surgery tumors of the CPA grow faster in females than in males.