Immunotherapy with Pembrolizumab beyond Progression and Local Ablative Therapy in Oligoprogressive metastatic NSCLC

Immune checkpoint inhibitors (ICIs) targeting PD-(L)1 are standard first-line treatment for non-oncoge-addicted metastatic non-small cell lung cancer (mNSCLC). While disease progression typically requires therapy change, patients with oligoprogression (≤5 progressing sites) often continue ICI in combination with local ablative therapies. In this retrospective study, we aim to evaluate the characteristics and outcomes of this treatment approach.

We retrospectively analyzed mNSCLC patients receiving first-line ICI-based therapy at University Hospital Basel (January 2016-March 2022). Patients with documented disease progression were categorized into: treatment beyond progression (BPD), second-line treatment (2L), or best supportive care (BSC). We compared patient characteristics and overall survival (OS).

Of 104 patients receiving first-line ICI treatment, 65 experienced disease progression: 21 (32%) received BPD, 30 (46%) received 2L, and 14 (22%) received BSC. Patient and disease characteristics were similar across groups, except for higher brain metastasis frequency in the BPD group (BPD: 67% vs 2L: 20% vs BSC: 29%; p=0.002). After median follow-up of 17.9 months, time to first progression (5.4 vs 5.3 months, p=0.5) and median OS after progression (9.1 vs 10.9 months, p=0.35) were similar between BPD and 2L groups.

In this retrospective analysis, treatment BPD was not associated with an improved prognosis compared to 2L therapy. There is a need to improve and implement criteria to select patients who truly benefit from this treatment approach.