P63.06 Immunotherapy Improved Pathological Response for Resectable Limited Stage Small Cell Lung Cancer- A Case Serial

Abstract

As one of the most lethal cancers, small cell lung cancer (SCLC) stepped into the era of immunotherapy with the approval of anti-PD-L1 as standard therapy for extended stage SCLC. There are still some unmet needs for the limited stage SCLC. Here we report a small case series of the immunotherapy plus chemotherapy as neoadjuvant therapy for limited stage SCLC which achieved improved pathological response. Three patients were diagnosed as limited stage SCLC as nodal stage N1-N2 in Beijing Chest Hospital. All these patients received atezolizumab and standard chemotherapy (carboplatin plus etoposide) for 2-3 cycles, and underwent re-evaluation for the response and the possibility for R0 resection in Multi-disciplinary team (MDT). As the suggestion by MDT, all these patients underwent surgical resection after the neoadjuvant therapy. The general baseline data was shown in Table 1. All three patients were re-evaluated down-staging as good PR after 2-3 cycles neoadjuvant therapy, especially for the nodal dowstaging in these patients. The possibility of R0 resection was fully discussed. As for the suggestion from MDT, these patients were evaluated as resectable and operable. They all received lobectomy and lymphadenectomy by the traditional thoracotomy instead of the video-assisted thoracic surgery (VATS). The post-operation pathological results proved R0 resection for all these patients. Further, the results indicated pathological complete response in one patient (Figure 1) and pathological MPR in the other two patients, and all the dissected mediastinal lymph nodes were tumor free. Based on this result, we registered a single arm trial (ChiCTR2100042367) for the further study of this combination therapy for limited stage SCLC as neoadjuvant therapy.Table 1The General Data of Three patients received Neoadjuvant ThereapyPatient 1Patient 2Patient 3GenderFemaleMaleFemaleAge495143Smoking statusNeverNeverNeverTNM stageT2N1M0T3N1M0T2N2M0Cycles before surgery233Pathological responsepCRMPRMPR Open table in a new tab Immunotherapy combined with chemotherapy as neoadjuvant therapy could induce significant pathological response and give the opportunity of R0 resection in some limited stage SCLC patients, which is worth to be further explored.