Rhabdoid meningiomas: Clinicopathological analysis of a rare variant of meningioma.

INTRODUCTION: Rhabdoid Meningiomas (RM) are rare malignant type of meningiomas, classified as grade III in the WHO classification. Only a few case series have been reported, and factors affecting prognosis are still unclear.

METHODS: We did a retrospective chart review of all the RMs diagnosed in our institute between 2007 and 2019. Demographic profile, clinical status, imaging, surgical procedures used, post-operative course, adjuvant therapy and follow-ups were reviewed. Histopathological slides were also reviewed.

RESULTS: There were 11 patients with RM who underwent 17 surgical procedures between them. Median age was 26 years. On imaging, four had lesions in skull base, three in convexity and four in parasagittal region. Five patients had lesions which had bled and two had leptomeningeal dissemination. Two patients underwent Simpson's grade 1 excision, seven underwent grade 2 and one patient each underwent grade 3 and 5 excisions. One patient presented with poor sensorium and underwent surgery but ultimately succumbed. All reported patients had Rhabdoid features (>50%). Features of anaplasia were seen in four cases and atypical meningioma in others. The median progression-free-survival and overall survival was 6 months and 9 months, respectively. Female gender (n = 5; p = 0.032) and patients who received radiotherapy (p = 0.030) had a survival advantage. Location of the tumor (p = 0.43), presence of hemorrhage in the lesion (p = 0.49), grade of excision (p = 0.40) and WHO pathological grade (p = 0.11) did not have a statistically significant survival benefit.

CONCLUSION: Female gender and adjuvant radiotherapy were associated with survival advantage in our sample. Large studies are required to establish the factors associated with survival.