Anthony Dominick1* and Weijing Sun2
1Department of Hematology and Oncology, University of Kansas Medical Center, USA
2Department Medical Oncology, University of Kansas School of Medicine, USA
Treatment of locally advanced and metastatic gastric cancer has continued to be challenging and overall prognosis from this disease has remained poor with conventional chemotherapy. Through prospective and retrospective investigations, gastric carcinomas deficient in mismatch repair proteins have proven to be responsive to immune checkpoint blockade in the metastatic setting. We present a case of a patient with diffuse peritoneal metastatic gastric carcinoma and deficient in mismatch repair proteins who is effectively treated with single agent immune checkpoint blockade. This case is of interest as we have interval biopsy of disease demonstrating a robust inflammatory response within the tumor stroma and over 17 months of response and dramatic improvement in performance status while on immunotherapy. While this may only be applicable to a small subgroup
of patients it represents a therapy with significant improvement in anti-tumor activity compared to conventional chemotherapy. This also highlights the importance of checking clinically meaningful biomarkers as well as the need to identify science-based tumor and patient specific markers that will allow us to better select treatment for each patient in the future.
Dominick A, Sun W. Successful Treatment of Metastatic Gastric Carcinoma Deficient in Mismatch Repair Proteins with Immune Checkpoint Blockade: A Case Report and Review of the Literature. Clin Oncol. 2019;4:1672.