NCOG-02. ASSESSING THE INFLUENCE OF ADJUVANT INTERSTITIAL BRACHYTHERAPY ON MALIGNANT BRAIN TUMOR PATIENTS: INSIGHTS FROM THE NATIONAL READMISSION DATABASE

Abstract Interstitial brachytherapy (IB) is a form of surgically administered radiotherapy involving the implant of radioactive seeds into the resection cavity after tumor excision. Advances in IB for brain cancers have revived interest in this treatment platform. However, the impact of this therapy on hospital quality measures remains poorly characterized. Here we utilized the National Readmission Database (NRD) to address this gap in knowledge. We identified patients with malignant brain tumors who had undergone either craniotomies (C) for tumor resection or craniotomies augmented with adjuvant interstitial brachytherapy (C+IB) in the National Readmission Database (NRD, 2010-2018). Propensity-score weighting and survey regression techniques were used for analysis. Over the study period, the number of craniotomies with adjuvant interstitial C+IB steadily decreased. For brain metastasis (BM) patients, C+IB and C patients exhibited comparable length of hospital stay (IRR:0.95, CI95:0.61-1.50, p=0.838) and routine discharge to home or self-care (OR:1.01, CI95:0.86-1.18, p=0.918). However, primary brain tumor (PBT) patients who underwent C+IB showed longer hospital stay (IRR:1.43, CI95:1.03-1.99, p=0.032) and are less likely to undergo routine discharge (OR: 0.38, CI95:0.20-0.74, p=0.005) relative to the C cohort. Despite these differences, C+IB and C patients showed comparable 30- or 90- day readmission risk. The profile of readmission diagnoses was also similar. Cost-analysis suggests that IB increased the median total charge by $19,184 (p=0.003). Our analysis suggests that adjuvant interstitial brachytherapy did not alter hospital course/readmission risk for brain metastasis patients. However, PBT patients who underwent this therapy showed longer hospitalization and increased likelihood for non-routine discharge.