Limited Surgery and Conformal Photon Radiation Therapy for Pediatric Craniopharyngioma: Long-Term Results From the RT1 Protocol.

Abstract

PURPOSE/OBJECTIVE(S)\nTo estimate long-term disease control and selected complications for children and adolescents with craniopharyngioma after treatment with limited surgery and conformal photon radiation therapy (CRT) at a single institution. To benchmark outcomes to guide new treatment approaches, interventions, and surveillance.\n\n\nMATERIALS/METHODS\nA total of 101 pediatric patients with craniopharyngioma were prospectively enrolled on a phase II single institutional protocol beginning 1998. Surgery was individualized to treat presenting symptoms, reduce the irradiated volume, and avoid diabetes insipidus (DI). CRT (54Gy) was administered using a 1.0cm or 0.5cm clinical target volume margin and MRI was used during treatment to monitor the targeted volume. Patients were followed in the radiation oncology clinic for 10 years. Follow-up included serial MRI/MRA and a battery of tests to measure CNS effects.\n\n\nRESULTS\nTumor progression was experienced by 20 patients. The median time to progression was 5.1 years. Death occurred in 12 patients who experienced tumor progression (n\u202f=\u202f6), complications related to tumor or treatment (n\u202f=\u202f5) or both (n\u202f=\u202f1). With a median follow-up of 14.94 years for survivors, the 10-year estimates (± SE) of progression-free, event-free, and overall-survival were 78.84% ± 4.10%, 77.12% ± 4.19%, and 96.02% ± 1.95%, respectively. The 10-year cumulative incidence (± SE) of secondary tumor (1.99% ± 1.40%), secondary malignant tumor (1.0% ± 1.0%), necrosis (1.98% ± 1.39%), vasculopathy (8.47% ± 2.90%), and other permanent neurologic deficits (8.28% ± 3.37%) were estimated with tumor progression, secondary malignancy and death as competing risks. Three patients required revascularization surgery. Surgery was characterized by tumor-directed procedures: none (n\u202f=\u202f5), single (n\u202f=\u202f50), and multiple (n\u202f=\u202f46). Excluding those who presented with DI (n\u202f=\u202f7), there was no difference in prevalence of DI by number of procedures; however, the single procedure group had a higher incidence of DI after craniotomy compared to bur hole procedures (P < 0.001). Salvage therapy was successful in 13 patients using combinations of surgery and radiosurgery. Including frontline and salvage therapy, the incidence of diabetes insipidus (62%), growth hormone (82%), thyroid hormone (92%), adrenal hormone (89%), and sex hormone (81%) replacement therapies were individually assessed. Seizures that required treatment were observed in 19% and aspirin therapy was prescribed in 23%.\n\n\nCONCLUSION\nLimited surgery and CRT using photons results in excellent tumor control. Pediatric patients with craniopharyngioma experience a wide range of complications. The incidence and severity of complications may be further reduced by improving the type and extent of surgery procedures, newer methods of irradiation, and improving patient compliance with follow-up.