Neoadjuvant attelizumab combined chemotherapy in limited-stage and resectable small cell lung cancer: A multicentric, single-arm and open study.

Abstract

e20615 Background: Combine chemotherapy and immunotherapy have become the first-line treatment program for extensive small cell lung cancer. The aim of this study is to explore the safety and efficacy of neoadjuvant chemotherapy and immunotherapy in limited-stage small cell lung cancer. Methods: Treatment-naïve patients were enrolled and the patients received the 2-3 cycles of neoadjuvent chemotherapy and atezolizumab (1200mg, D1). surgery was performed within 4-6 weeks after the last treatment. The primary endpoint was surgery patients pathological complete response (PCR). Safety was assessed by adverse events (AEs) and postoperative complications. This trial was registered at the Chinese Clinical Trial Registry (Registration Number: (ChiCTR2100042367). Results: Recruitment started in May 2020. We reported 9 patients with neoadjuvent immunochemotherapy who have completed surgical treatment. Baseline characteristics: 7 males, with an average age of 52.1 years old, all ECOG PS 0-1; 6 current smokers; clinical stages IIB / IIIA / IIIB n = 6 / 1 / 2. There were 1 atezolizumab treatment-related Gr1 AEs (rush) and 4 treatment-related Gr 3-4 AEs. According to Recist 1.1, all patients achieved partial response. 9 patients completed surgery, 3 patients received bilobectomy, and 3 patients underwent pneumonectomy. Surgical methods included robot-assisted thoracoscopic surgery (RATS) /video-assisted thoracoscopic surgery (VATS) (3, 33.3%) and thoracotomy (6, 66.7%). Complete resection (R0) was achieved in 100% of patients (9/9). The mean operation time was 136 min; the mean bleeding volume was 194.4ml, and the mean hospital stay was 8.9 days. The postoperative pathology results showed a PCR (66.7%) in 6 patients and a MPR (88.9%) in 8 patients. Conclusions: Neoadjuvant chemotherapy and atezolizumab therapy significantly improves PCR in small cell lung cancer without unknown AE events and no surgical delay, so this protocol is safe and feasible. Whether the survival benefit is still unknown. Keywords: neoadjuvant therapy, Small cell lung cancer, immunotherapy, surgery, PCR. Clinical trial information: ChiCTR2100042367. [Table: see text]