OUTCOMES IN SECOND LINE CHEMOTHERAPY FOR THE TREATMENT OF GLIOBLASTOMA MULTIFORME (GBM). THE EXPERIENCE OF A TERTIARY CENTRE: RESPONSE RATE VERSUS QUALITY OF LIFE

Abstract AIMS To date, there is limited analysis of the overall survival (OS) of patients receiving second-line chemotherapy in the treatment of recurrent GBM, compared with reported quality of life (QOL). Previously, PCV (Procarbazine, Lomustine, Vincristine) chemotherapy was standard of care, but recently Lomustine alone has been favoured due to reduced hospital contact time for patients, whilst conferring similar response rates (RR) to PCV. This project examines the outcomes between the two chemotherapy groups to help inform treatment decisions in the real-world setting. METHODS Data was collected retrospectively between June 2016 and December 2023. 52 patients received PCV and 16 pa- tients received Lomustine. Patients must have had a WHO grade 4 histological diagnosis and received chemora- diotherapy at initial presentation. Radiological or clinical response was recorded, as well as OS following second-line chemotherapy. Chemotherapy toxicity was analysed by type and grade and used as a marker of QOL. RESULTS 8 (11.8%) patients overall responded to treatment. The RR was 11.5% (6/52) for PCV and 12.5 % (2/16) for Lomus- tine. The median OS from the start of second- line chemotherapy was 265 (range 61-1947) days vs 185 (range 42-424) days for PCV and Lomustine respectively. 7 patients were still alive at the time of analysis. 4 received PCV and 3 received Lomustine. 29 (55.8%) of the patients who received PCV had 1+ toxicity. 8 (15.4%) had 2+ toxicities. 5 (9.6%) had a grade 2 (G2) toxicity. The most common side effect was fatigue, followed by haematological toxicity and GI disturbance. 1 developed hepatotoxicity. With Lomustine, 6 (37.5%) had 1+ toxicity recorded. 1 (6.3%) experienced a G2 toxicity. CONCLUSION RR is poor to both PCV and Lomustine, with both conferring side effects. PCV requires intravenous adminis- tration and frequent hospital contact. OS is similar between the PCV and Lomustine groups, although further analysis is required due to small numbers.