RT-12OUTCOMES IN MEDULLOBLASTOMA: SINGLE INSTITUTION CASE SERIES

BACKGROUND: We have seen a paradigm shift in terms of use of radiation technology for the treatment of patients with medulloblastoma, from conventional 2-D shifting fields to 3-D CRT, IMRT and proton therapy. Similarly from prone to supine position and reduced dose to the cranio-spinal axis with an intent to have equivalent outcomes with reduced probability of late sequelae including second malignancies. METHODS: We have analysed data of 21 consecutive patients in May 2014, registered and treated in our hospital between 2002 and 2011. The cohort consisted of 14 male and 7 female patients with a median age of 8 (Range 3-30) Years. With no known co-morbidities and median KPS of 70 they all had tumors mostly in the IV ventricle(43%) and cerebellum(38%), for which they underwent surgery including decompression(72%) subtotal excision(9%), near total or total excision(19%). All patients were histologically grade IV medulloblastoma who underwent adjuvant radiation alone (40%) or followed by chemotherapy (60%) based on the risk stratification. 57% received 3D CRT in supine position while rest are treated with conventional techniques, median dose given to cranio-spinal axis was 23.4 Gy, posterior fossa was 36 Gy and to the tumor bed was 55.8 Gy at 1.8Gy per fraction. Chemotherapy was usually procarbazine/cisplatin/vincristine based regimen. Regular IQ, endocrine, ophthalmic and auditory evaluation was done in all the patients on follow-up. RESULT: Overall survival at 5 year was documented at 45% and 10 year survival at 35% for the entire cohort taking worst case scenario.3/13 patients developed IQ problems, 7/13 developed endocrine dysfunction, 3/12 developed auditory abnormality. CONCLUSION: Outcome of this cohort is comparable to the literature on risk group stratification. More importantly, risk adapted strategy for the treatment was found to be technically and logistically feasible and effective for a comparatively rare tumor in our setup.