Local ablative treatment and treatment beyond progression for oligo-progression in stage IV non-small cell lung cancer after tumour response to anti-PD1 treatment

Background Anti-PD1 immunotherapy has emerged as a gold-standard treatment in stage IV non-small cell lung cancer (NSCLC). Despite long-term disease control in 5-20% of patients, secondary resistance often occurs. Local ablative treatment (LAT) and treatment beyond progression for oligo-progressive disease may improve long-term outcomes in stage IV non-small cell lung cancer after tumor response to anti-PD1 treatment. Methods In this retrospective multicentric cohort study, stage IV NSCLC patients treated with LAT for oligo-progression after initial tumor response to anti-PD1 were identified using electronic medical records from 3 centers. Here are reported clinical characteristics and outcomes of 27 patients. Quantitative data were summarized as median. Survival was estimated using Kaplan-Meier method. Results Twenty-seven patients received 31 LAT with surgery (n = 3, 10%), stereotactic radiotherapy (n = 18, 58%) or conformational radiotherapy (n = 10, 32%) after nivolumab (n = 19, 70%) or pembrolizumab (n = 8, 30%) treatment. Patients received anti-PD1 treatment in first (n = 3, 11%), second (n = 18, 67%) or third-line (n = 6,22 %) for stage IV NSCLC (adenocarcinoma/ squamous/not-otherwise specified: 18/8/1; PDL1 not evaluated/negative/1-49/>50: 10/8/1/6). Oligo-progression site was: brain (n = 19, 61%), lung (n = 5, 16%), adrenal gland (n = 2, 6%) and bone (n = 4, 13%). Anti-PD1 treatment was continued beyond progression after LAT in 22 (81%) patients. Oligo-progression occurred 6.9 months after anti-PD1 initiation. Progression Free Survival (PFS) after oligo-progression was 13.1 months (IC95: 7.0-not reached). Nine (33%) patients experienced ≥1 grade ≥2 immune adverse event before LAT. One patient had grade 3 toxicity after LAT (cerebral radionecrosis). Overall survival was not mature after a median follow-up of 9.1 months from LAT. Data will be updated before presentation and subgroup analysis will be presented. Conclusions LAT and treatment beyond progression for oligo-progression after initial tumor response to anti-PD1 treatment provide encouraging survival outcomes in selected stage IV NSCLC patients. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure F. Guisier: Honoraria (self), Advisory / Consultancy: BMS; Honoraria (institution), Advisory / Consultancy: MSD / Merck US; Honoraria (self), Advisory / Consultancy: Roche; Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (institution): Boehringer Ingelheim. R. Gervais: Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy: Roche; Honoraria (self), Advisory / Consultancy: Boehringer Ingelheim. M. Geier: Honoraria (self): BMS; Honoraria (self): MSD / Merck US. R. Corre: Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: BMS; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Roche; Travel / Accommodation / Expenses: MSD / Merck US. R. Descourt: Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy: Boehringer Ingelheim; Honoraria (self), Advisory / Consultancy: Roche. C. Chouaid: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: BMS; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: MSD / Merck US; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: AstraZeneca. All other authors have declared no conflicts of interest.