1097P - Durable relapse-free survival in stage IV melanoma patients (pts) treated with neoadjuvant immune-checkpoint inhibitor (ICI) followed by local procedures

Background

Achieving a complete response (CR) with ICI is associated with a long term survival in advanced melanoma pts. The long term outcome of pts for which the CR is obtained by a local procedure (LP) such as surgery, radiotherapy or interventional radiology following ICI is not known. We report here long term relapse-free survival (RFS) and overall survival (OS) data of a cohort of pts in this situation.

Methods

RFS and OS of melanoma pts with a CR obtained by ICI + LP were estimated from the time of LP to progression or death using the Kaplan-Meier method. Pts with no viable cells in the resected metastases were excluded.

Results

40 pts (57.5% males) with a mean age of 52.4 years achieved a CR after receiving ICI combined by an additional LP on 1 to 3 stable or progressing metastatic sites including lymph nodes, skin, lung, liver and brain. Most pts had received previous treatment lines (mean: 2.9). 23 (57.5%) pts were in progression according to RECIST 1.1 before the LP, 5 (12.5%) pts were in partial response, and 1(2.5%) pt in stable disease. 4 (10%) pts had a dissociated response and for 7 (17.5%) pts the response was not evaluable. Median duration between ICI onset and LP was 8.9 months [3.9–16.4]. After a median duration of follow-up of 5.4 years from LP, the median duration of response was not reached, 5 years RFS and OS rates were 58.65% [44.52–77.27] and 88.57% [78.63–99.76] respectively. Median RFS and OS were not reached. Relapses occurred in 14 (35%) pts, most often on a site different from that treated by the LP.

Conclusions

This real life study shows that long term RFS and OS can be achieved when ICI is given before a LP at oligometastatic sites in spite of tumor progression following ICI and suggests that neoadjuvant ICI should be evaluated in stage IV pts.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Caroline Robert.

Funding

Has not received any funding.

Disclosure

E. Routier: Financial Interests, Personal and Institutional, Other, Compensation: BMS, Novartis, Pierre Fabre; Financial Interests, Personal and Institutional, Invited Speaker: BMS, Novartis, Pierre Fabre. C. Boutros: Financial Interests, Personal and Institutional, Advisory Board: BMS; Financial Interests, Personal and Institutional, Invited Speaker: MSD; Financial Interests, Personal and Institutional, Other, Meeting fees: Pierre Fabre. C. Robert: Financial Interests, Personal and Institutional, Advisory Role: BMS, Novartis, Pierre Fabre, MSD, Roche, Sanofi, AstraZeneca, Merck; Financial Interests, Personal, Other, Cofounder of Ribonexus. All other authors have declared no conflicts of interest.