Benchmarking Safety Indicators of Surgical Treatment of Brain Metastases Combined with Intraoperative Radiotherapy: Results of Prospective Observational Study with Comparative Matched-Pair Analysis.

Intraoperative radiotherapy (IORT) of the operative cavity for surgically treated brain metastasis (BM) has gained increasing prominence with respect to improved local tumor control. However, IORT immediately performed at the time of surgery might be associated with increased levels of perioperative adverse events (PAEs). In the present study, we performed safety metric profiling in patients who had undergone surgery for BM with and without IORT in order to comparatively analyze feasibility of IORT as an adjuvant radiation approach. Between November 2020 and October 2021, 35 patients were surgically treated for BM with IORT at our neuro-oncological center. Perioperative complication profiles were collected in a prospective observational cohort study by means of patient safety indicators (PSIs), hospital-acquired conditions (HACs), and specific cranial-surgery-related complications (CSCs) as high-standard quality metric tools and compared to those of an institutional cohort of 388 patients with BM resection without IORT in a balanced comparative matched-pair analysis. Overall, 4 out of 35 patients (11%) with IORT in the course BM resection suffered from PAEs, accounting for 3 PSIs (9%) and 1 HAC (3%). Balanced matched-pair analysis did not reveal significant differences in the perioperative complication profiles between the cohorts of patients with and without IORT (