474 Multiple combinational strategies of immunotherapy for esophageal squamous cell carcinoma: one institutional experience in Taiwan since 2016

Background Esophageal squamous cell carcinoma is still a health burden in Taiwan. In R/M setting, the prognosis becomes worse. ESCC is still an immunogenic cancer. In randomized 2nd line ATTRACTION-3 study(nivolumab vs taxane after PF failure), median OS improved from 8.4 months in chemotherapy to 10.9 months in nivolumab(HR, 0.77; 95% CI, 0.62–0.96; p =0.019). The median duration of response was 3.9 months and 6.9 months. Nivolumab is a new 2nd line option for ESCC. Methods From early 2016 to early 2020, 15 advanced ESCC patients had ever received immunotherapy-containing regimens in Yun-lin Branch of National Taiwan University Hospital and were analyzed. Results The overall response to immunotherapy-containing regimens was 60%(9/15) and clinical benefit was 80%(12/15). 2nd line nivolumab was given in 3 cases; response rate was33% and clinical benefit was 67%. 2nd line afatinib combined with anti-PD1 was given in 9 case; response rate was 67% and clinical benefit was 78%. The response rate of 2nd line afatinib & pembrolizumab was 75%(3/4); however, Gr. III pneumonitis & Gr. II hepatitis were noted in the patient with progression. The response rate of 2nd line afatinib & nivolumab was 60%(3/5) and clinical benefit was 80%(4/5); skin rash and diarrhea were often found. 1st line afatinib combined with anti-PD1 was given in 3 patients; response rate was 67% and clinical benefit was 100%. The response rate of 1st line afatinib & nivolumab was 100%(2/2). Conclusions EGFR TKIs have multiple immuno-modulatory effects and may increase immunotherapy benefits in ESCC. Anti-PD1 and anti-CTLA4, another possible rationale, could bring more benefits maybe in 1st line CheckMate649 study. Acknowledgements Nil Trial Registration N/A Ethics Approval N/A Consent Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal. References Nil