M5 - International Comparison of Oncologic Outcomes after Isolated Limb Infusion (ILI) for Advanced Melanoma
Monday, February 17, 2020
8:15 AM – 8:30 AM
Location: Sebastian I 1/2
Introduction: ILI is a minimally invasive procedure to deliver high-dose chemotherapy to extremities affected by locally advanced or in-transit melanoma. This international study compares outcomes of melanoma patients treated with ILI in the US and Australia.
Methods: We identified AJCC 7 stage 3B/3C melanoma patients treated with ILI at 4 US and 5 Australian centers between 1992–2018. Primary outcomes were treatment response, in-field (IPFS), distant (DPFS) progression free survival and overall survival (OS) evaluated by Kaplan-Meier method. Multivariate analysis evaluated whether ILI after immunotherapy approval affected outcomes.
Results: Among 687 patients, median age was 71 years (IQR 62-79). At the time of ILI, patients were stage 3B (n=383, 56%) and 3C (n=304, 44%) mostly with lower extremity disease (n=610, 88%). More ILIs were performed in Australia (n=411, 60%) than the US (n=276, 40%). In Australia, more ILIs were performed for stage 3B disease than the US (62% vs 46%; p<0.001). Overall response (complete + partial response) was higher among Australian patients (73% vs 53%, p<0.001). Among stage 3B patients, the Australian cohort had better IPFS (p=0.001). Among stage 3C patients, the US cohort had better OS (p<0.0001). Availability of immunotherapy did not affect IPFS or DPFS in either country; in the US, stage 3C patients that received ILI after ipilimumab approval had significantly improved OS (HR=0.63, p=0.02).
Conclusions: In Australia, patients are treated at an earlier disease stage (3B) than the US with better IPFS. In the US, stage 3C patients have better OS associated with approval of immunotherapy.