First-line atezolizumab/durvalumab plus platinum–etoposide combined with radiotherapy in extensive-stage small-cell lung cancer

Abstract

Background Immunotherapy has made significant advances in the treatment of extensive-stage small-cell lung cancer (ES-SCLC), but data in combination with radiotherapy are scarce. This study aims to assess the safety and efficacy of chemoimmunotherapy combined with thoracic radiotherapy in patients with ES-SCLC. Methods This single-center retrospective study analyzed patients with ES-SCLC who received standard platinum–etoposide chemotherapy combined with atezolizumab or durvalumab immunotherapy as induction treatment, followed by consolidative thoracic radiotherapy (CTRT) before disease progression in the first-line setting. Adverse events during radiotherapy with or without maintenance immunotherapy and survival outcomes were assessed. Results Between December 2019 and November 2021, 36 patients with ES-SCLC were identified to have received such treatment modality at one hospital. The number of metastatic sites at diagnosis was 1–4. The biological effective dose of CTRT ranged from 52 to 113 Gy. Only two patients (6%) developed grade 3 toxic effect of thrombocytopenia, but none experienced grade 4 or 5 toxicity. Four patients developed immune-related pneumonitis during the induction treatment period but successfully completed later CTRT. The rate of radiation-related pneumonitis was 8% with grades 1–2 and well tolerated. The median progression-free survival (PFS) was 12.8 months, but the median overall survival (OS) was not determined. The estimated 1-year OS was 80.2% and 1-year PFS was 53.4%. Conclusions Immunotherapy combined with CTRT for ES-SCLC is safe and has ample survival benefit.

Efficacy and safety of thoracic radiotherapy in extensive-stage small-cell lung cancer patients receiving first-line immunotherapy plus chemotherapy: a propensity score matched multicentre retrospective analysis

“…Diamond et al performed a single-arm retrospective study enrolling 20 patients and found favorable safety profile and improved OS (median OS) with the use of TRT and ICIs plus CHT in the management of ES-SCLC [ 45 ]. Another single-arm retrospective analysis included 36 patients also suggested that combined with TRT in the first-line treatment was safe and had ample survival benefits [ 46 ].…”

Treatment patterns and clinical outcomes in 157 patients with extensive-stage small cell lung cancer: real-world evidence from a single-center retrospective study

“…However, no conclusion was reached regarding ES-SCLC. Some studies thought ICIs plus radiotherapy could prolong survival ( 36 , 37 ), but the toxicity caused by radiation plus ICIs can limit this function ( 38 ).…”

Radiotherapy for extensive-stage small-cell lung cancer in the immunotherapy era

“…But a retrospective study including 41 patients with ES-SCLC, 23 patients received 30Gy/10 fractions cTRT after systemic therapy and 18 patients did not receive cTRT, showed that cTRT significantly improved OS compared with systemic therapy only group (1-year OS 78.6% vs. 39.7%, p=0.019 ( 39 ). Furthermore, several single-center retrospective studies have also demonstrated a survival benefit of cTRT after first-line chemoimmunotherapy ( 40 , 41 ). Given that all existing studies are retrospective, the role of cTRT in ES-SCLC in the immunotherapy era should be interpreted with caution, and we look forward to the prospective study results.…”

“…A real-world study showed that cTRT after first-line chemoimmunotherapy did not increase the incidence of adverse events compared with systemic therapy alone ( 41 ). A retrospective study involving 36 patients with ES-SCLC who received first-line chemoimmunotherapy followed by cTRT at 60Gy/28 fractions in most patients, showed that 8% of patients developed radiation-related pneumonitis, all of which were grade 1-2, and four patients discontinued immunotherapy after immune-related pneumonitis but completed cTRT ( 40 ). Thus, cTRT has a survival benefit and can be tolerated.…”