Phase II study of multidisciplinary therapy combined with pembrolizumab for patients with synchronous oligometastatic non-small cell lung cancer TRAP-OLIGO study (WJOG11118L): Feasibility analysis of induction therapy and local ablative therapy.

8564 Background: Several clinical trials have shown that local ablative therapy (LAT) to all sites of the disease might provide survival benefit for patients with oligometastatic non-small cell lung cancer (NSCLC). Few studies have evaluated feasibility of multiciliary therapy combined immune-checkpoint inhibitor plus chemotherapy with LAT to all sites of disease. Methods: This multicenter, single-arm, phase II trial enrolled untreated patients with stage IV NSCLC who had 3 or fewer metastatic lesions. All patients had received 2–4 cycles of a systemic treatment including pembrolizumab and platinum-doublet chemotherapy as induction therapy. LAT was administered to all residual lesions after induction therapy, followed by maintenance therapy including pembrolizumab. The primary endpoint is the progression-free survival (PFS) rate of 24 months from the date of initiation of LAT. The secondary endpoints are safety, response rate of induction therapy, PFS, overall survival, and proportion of implementation. The present analysis showed feasibility of induction therapy and LAT. Results: Between October 30, 2020, and August 12, 2022, 30 patients were enrolled. The number of metastases at diagnosis was one in 7 patients (7/30, 23%), two in 14 patients (14/30, 47%), and three in 9 patients (9/30, 30%). All patients received induction therapy, and the objective response rate was 21/30, 70% (95% confidence interval, 50% to 85%). Adverse events of grade 3/4 occurred in 21/30, 70%, including neutropenia (5/30, 17%), anemia (2/30, 7%), and thrombocytopenia (2/30, 7%). Seven patients did not receive planned LAT for the following reasons: disease progression (N=3), adverse events (N=2; pneumonitis grade 2, and hepatitis grade 3), sudden death (N=1), and one patient had proven stage III after induction therapy. Twenty-three patients (23/30, 77%) received planned LAT to all sites of residual disease. As LAT, five patients received surgery only, 12 patients received radiotherapy only, and 6 patients received both surgery and radiotherapy. Eighteen patients completed planned radiotherapy for 32 lesions (primary sites 22%, lymph node 25%, bone 25%, pulmonary metastasis 19%, brain 6% and adrenal 3%). Eleven patients received surgery (primary sites and lymph node) as LAT. Grade 3/4 adverse events during LAT occurred in 3 patients (3/23, 13%): rash (n=1), hypoxia (n=1) and CPK increased (n=1). There were no treatment-related deaths. Conclusions: Results of the TRAP-OLIGO study showed that multimodality treatment with platinum-based chemotherapy plus pembrolizumab and LAT had favorable implementation, and planned LAT was feasible in this population. Clinical trial information: jRCTs041200046 .