GCT-24. RELAPSE PATTERN AND QUALITY OF LIFE IN PATIENTS WITH LOCALIZED GERMINOMA ORIGINATING FROM BASAL GANGLIA REGION

BACKGROUND: The optimal radiation field in localized basal ganglia (BG) germinoma was not well defined, mostly due to unknown relapse patterns. In our institute, both focal radiotherapy (FR) and craniospinal irradiation (CSI) plus boost were considered in this population until whole-brain radiotherapy (WBRT) plus boost became an option in 2008. Thus, a retrospective study was conducted to address the issue. Furthermore, the health-related quality of life (HRQOL) was also evaluated. METHODS: Patients who were diagnosed as localized BG germinoma between 2000 and 2017 were studied. HRQOL was evaluated by PedsQL 4.0 (≤15 years) and SF-36 (>15 years) questionnaires based on the age at last follow-up. RESULTS: Among 161 patients included, 35 patients received FR, 109 patients received WBRT plus boost, and 17 patients received CSI plus boost. After a median follow-up of 83 months (range, 13 to 214 months), 15 patients relapsed in FR group, 4 in WBRT group and 0 in CSI group. The 5-year DFS was 74.3%, 97.2%, and 100%, respectively (p<0.001). Among 15 patients who relapsed after FR, 14 had positive radiological findings, in which 6 (42.8%) had lesions documented at the periventricular area, and 7 (50.0%) in the frontal lobe. HRQOL data were available in 69 patients, which generally scored low. In 38 patients evaluated by SF-36, those receiving CSI had significantly lower mental component scores than those receiving WBRT (p=0.027) or FR (p=0.011). CONCLUSIONS: Patients with localized BG germinoma present a unique relapse pattern. WBRT, which covers at-risk areas, showed both better disease control and HRQOL.