SECOND RADIOTHERAPY TREATMENT IN RECURRENT BRAIN TUMORS

BACKGROUND: Radiotherapy for recurrent irradiated brain tumors is limited by toxicity. The purpose of this study is to determine whether second radiotherapy treatment is beneficial or not for patients with recurrent brain tumors. PATIENTS AND METHODS: In a prospective study, 11 patients who recurred after primary brain tumors, first treated between 2005-2012, were analyzed for second radiotherapy treatment. Tumor histologic types are: glioblastoma multiforme (7), grade 2 astrocytoma (2), grade 3 oligodendroglioma (1) and grade 3 oligoastrocytoma (1). First radiotherapy (RT1) was performed with TD= 50-60Gy, 2Gy/ fraction for 8 patients and TD = 30 GY, 3Gy/ fraction in one patient. DFS (disease free survival) until the recurrence was 5.3-90.6 months. Second radiotherapy treatment (RT2) was associated with surgery and chemotherapy in 8 patients, with surgery or chemotherapy 2 patients; radiotherapy alone was performed in one patient. Karnofsky Index (KI) at RT2 was >70 for 9 patients and <70 for 2 patients. RT2 was delivered with: TD = 44-10 Gy, 2 Gy/fraction, 8 patients; TD = 30-44 Gy, 2,66-3 Gy/ fraction, 3 patients. Site of recurrence, isodose distributions, PTV1 (RT1) and PTV2 (RT2), KI at the beginning and at the end of radiotherapy were compared. RESULTS: The sites of recurrences were: central and marginal, 7 patients, at distance 4 patients. The same volume was second irradiated in 4 patients. PTV2 was greater than PTV1 only for 3 patients. KI was unchanged at the end of RT2 for 10 patients. Deterioration was observed in one patient. The median follow-up was 9,22 months (5,8-20,6 months). Six patients are alive, and 5 are dead. The median follow-up was 9.22 months. CONCLUSION: There are few therapeutic options for patients with recurrent brain tumors. Regardless of histology, second radiotherapy could be one of these options alone or with other treatment methods for patients with good KI, surgery at time of recurrence and longer DFS from first treatment.