ESTRO 2024 - Abstract Book

S888

Clinical - CNS

ESTRO 2024

Results:

Data regarding 95 patients were collected, 70 AM and 25 ANM respectively. Mean age at diagnosis was 64 (range 31 86); 47 were males and 48 females. Clinical onset was mostly represented by epilepsy (22 patients, 23%). The majority of meningiomas (90, 94,7%) had a supratentorial location. 85 patients underwent a gross total resection (GTR), while 10 patients received a subtotal resection (STR). Simpson grade I resection was obtained in 82 patients, grade II in 3 patients, grade III in 4 patients and grade IV in 6 patients respectively. Adjuvant RT was prescribed in 36 patients (37.8%) patients : 23 patients received fractionated RT for a mean dose of 59Gy (range 54-60) while 13 patients received radiosurgery (SRS) as adjuvant treatment for a mean dose of 15Gy (range 15-21). 31 (33%) patients recurred, those recurrences were treated with: Surgery alone in 18 patients (50%); surgery followed by RT in 2 patients (5.6%) or with RT alone in 11 patients (44.4%). In AM, adjuvant RT had a detrimental effect on RFS at univariate analysis with a mean DFS of 48,3 months (95% CI for the mean 31,061-65,718) in the RT group versus a mean DFS of 94.3 months (95% CI for the mean 79,821-108,859) in the no RT group, however this effect was not confirmed at multivariate analysis. When stratifying for Simpson Grade, impact of RT on DFS was not confirmed (see Fig. 1).

In ANM patients, adjuvant RT had a statistically significant impact both on DFS (P = 0,0361) and OS (P = 0,0355) . In fact, patient with ANM undergoing adjuvant RT had a mean DFS of 65 months (95% CI for the mean 49,148-80,889) versus 32 months (95% CI for the mean 17,656 -46,42 ) in the no RT group and a mean OS of 61,5 months (95% CI for the mean 38,273-84,798) and 30,7 months (95% CI for the mean 15,811-45,657) respectively (Fig.2)