Abstract 3863
Background
Anti-PD1 immunotherapy prolongs recurrence-free survival when used as adjuvant therapy in high-risk resected melanoma. To date, detailed data on nature and management of recurrences following adjuvant anti-PD1 therapy are lacking.
Methods
All patients with resected stage III or IV melanoma who received adjuvant anti-PD1-based therapy (pembrolizumab or nivolumab) at two sites since 2015 and had a melanoma recurrence were included. Disease characteristics prior to adjuvant therapy, adjuvant treatments received, timing and nature of recurrences, and subsequent local and systemic management and their outcomes were examined.
Results
28 patients (pts) had a melanoma recurrence during or following adjuvant anti-PD1 therapy (including 5 on nivolumab/ipilimumab combination). Prior to adjuvant therapy, 26 patients had stage III (13 IIIB, 12 IIIC, 1 IIID), 2 had resected stage IV melanoma, 16 were male, median age 59 years, and 12 were BRAF V600 mutation positive (11 wildtype, 5 unknown). 22 (79%) recurred during adjuvant therapy, 6 recurred following cessation of therapy (1 after completing 12 months, 4 after ceasing early for toxicity, 1 withdrew consent). Median time to recurrence from surgery was 6.8mo (range 2.8-28.2). 15 recurrences were detected clinically and 13 on 3-monthly imaging. 13 (46%) recurrences were loco-regional only, and 15 distant (2 brain). 12 (43%) patients were treated with surgery at recurrence (10 local, 1 brain and 1 lung metastasis) to no evidence of disease, and 6 have subsequently recurred. Data on systemic therapy after recurrence (either 1st relapse or 2nd after salvage surgery) are in the Table. 3 of 17 (18%) treated with systemic therapy after recurrence have progressed. 1 (4%) patient has died, 9 months after recurrence.Table: 1252P
| Systemic treatment | N | Best RECIST response | ||||
|---|---|---|---|---|---|---|
| CR | PR | SD | PD | Not reached first scan | ||
| BRAF/MEKi | 7 | 1 | 3 | 0 | 1 | 2 |
| Anti-PD1 | 3 | 0 | 0 | 0 | 2 | 1 |
| Combination anti-PD1/-CTLA-4 | 4 | 1 | 1 | 0 | 0 | 2 |
| Combination anti-PD1/-LAG-3 | 2 | 0 | 0 | 0 | 1 | 1 |
| MEK+CDK4/6i | 1 | 0 | 0 | 0 | 1 | 0 |
| Total | 17 | 2 | 4 | 0 | 5 | 6 |
Conclusions
These data are the first to demonstrate the utility of salvage therapy for pts who progress early despite adjuvant anti-PD1. Early data suggest that this is a challenging group, likely to require multimodal treatment. Updated analyses will be presented.
Clinical trial identification
Legal entity responsible for the study
Melanoma Institute Australia.
Funding
Has not received any funding.
Editorial Acknowledgement
Disclosure
M.S. Carlino: Consultant advisor: Novartis, BMS, Merck MSD, Amgen, Pierre-Fabre. A.M. Menzies: Consultant advisor: BMS, Merck MSD, Novartis, Pierre-Fabre, Roche. G.V. Long: Consultant advisor: Amgen, Array, BMS, Merck MSD, Novartis, Pierre-Fabre, Roche. All other authors have declared no conflicts of interest.