Combined Proton and Photon Conformal Radiotherapy for Intracranial Atypical and Malignant Meningioma
CHRISTOS BOSKOS₪, LOIC FEUVRET†, GEORGES NOEL∞, JEAN-LOUIS HABRAND, PASCAL POMMIER٭, CLAIRE ALAPETITE, HAMID MAMMAR‡, REGIS FERRAND*, GILBERT BOISSERIE†, JEAN-JACQUES MAZERON†
*Institut Curie – Centre de Protonthérapie d’Orsay. Campus Universitaire, Batiment 101, 91898 Orsay Cedex, France
₪ 251 General Hospital of Airforce, 4, Kanelopoulou , Athens, Hellas
† Hôpital Pitié Salpêtrière, 47-83, boulevard de l’Hopital, 75651 Paris Cedex 13, France
∞ Centre Paul Strauss, 3, rue de la Porte de L’Hopital, 67085 Strasbourg Cedex, France
٭ Centre Léon Bérard, 28, rue Laennec, 69373 Lyon Cedex 08, France
‡ Centre Antoine Lacassagne , 33, avenue Valombrose, 06189 Nice Cedex 2, France
PURPOSE: To evaluate retrospectively the efficacy of conformal fractionated radiotherapy combining proton and photon beams after primary surgery for the treatment of atypical(AM) and malignant(MM) meningiomas.
PATIENTS AND METHODS: Between September 1999 and October 2006, 24 patients (12 males, 12 females) with histopathologically proven meningioma (atypical 19, malignant 5) received postoperative combined radiotherapy with a 201 MeV proton beam at the Centre Protontherapie d’Orsay (CPO) and a high energy photon beam . Six patients underwent gross total resection and eighteen a subtotal resection. Median gross tumor volume and clinical target volume were 44.7 cc and 153.3 cc, respectively. Mean total irradiation dose was 65.01 CGE (cobalt gray equivalent) with mean proton total dose 34.05 CGE and mean photon total dose 30.96 CGE.
RESULTS: The median follow up interval was 32.2 months [1-72]. The overall mean local relapse-free interval was 27.2 [10-50]months, 28.3 [10-50] for AM and 23 [13-33] for MM. Ten tumors recurred locally. One-, 2-, 3-, 4-, 5-, 8- year local control rates for the entire group of patients were: 82.9 ±7.8, 82.9±7.8, 61.3±11, 61.3±11, 46.7±12.3, 46.7±12.3, respectively. One-, 2-, 3-,4-,5-, 8- years overall survival rates were: 100%, 95.5±4.4, 80.4±8.8, 65.3±10.6, 53.2±11.6, 42.6±13, respectively. Survival was significantly associated with total dose. There was no acute morbidity of radiotherapy. One patient developed radiation necrosis 16 months after treatment.
CONCLUSIONS: Postoperative combination of conformal radiotherapy with protons and photons for atypical and malignant meningiomas is a well-tolerated treatment producing long-term tumor stabilization.