Abstract 1319P
Background
Immune checkpoint inhibitors (ICIs) represents a key stone of cancer treatment, including non-small cell lung cancer. Unfortunately, the efficacy of ICIs is poor in patient with bone metastases from NSCLC. Recently, several case reports have suggested the abscopal effect of radiotherapy in advanced NSCLC patients. However, whether this positive abscopal effect is applicable during ICIs treatment of NSCLC involving bones, remains to be established.
Methods
We retrospectively reviewed the records of patients with bone metastases who received ICIs as monotherapy (anti-PD1 or anti PD-L1) as well as in combination with platinum based-chemotherapy (carboplatin or cisplatin). We next analyzed the presence or the absence of radiotherapy targeting bone metastases among these patients during immunotherapy.
Results
A total of 40 patients were included in this study; among them 10 (25%) received palliative RT for symptomatic bone metastases during cancer immunotherapy treatment with ICIs (RT group); the remaining 30 (75%) patients did not receive bone irradiation (Non-RT group). We observed that the RT group had a significantly longer overall survival than the Non-RT group, with a median survival of 16 months in the RT group versus 3 months in the Non-RT group (Log Rank test p < 0.048; HR for OS = 0.44; 95%CI: 0.18-1.00). Similar results were observed with respect to progression free survival (LogRank test p < 0.016; HR for PFS = 0.34; 95% CI: 0.15-1.00).
Conclusions
Our results suggest that radiotherapy to bone metastases may improve ICIs efficacy in patients with bone metastatic NSCLC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.