Open AccessPD-1 blockade in neoadjuvant setting of DNA mismatch repair-deficient/microsatellite instability-high colorectal cancer.
Author(s) -
Dingxin Cancer Liu,
Dandan Li,
Jiang Wu,
Zhi-Zhong Pan,
Xiaoshi Zhang,
Pei-Rong Ding
Publication year - 2019
Publication title -
journal of global oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.002
H-Index - 17
ISSN - 2378-9506
DOI - 10.1200/jgo.2019.5.suppl.84
Subject(s) - medicine , microsatellite instability , colorectal cancer , blockade , oncology , pathological , neoadjuvant therapy , cancer , chemotherapy , retrospective cohort study , dna mismatch repair , gastroenterology , microsatellite , biochemistry , allele , chemistry , receptor , breast cancer , gene
84 Background: Although PD-1 blockade has significantly improved the survival of metastatic colorectal cancer with DNA Mismatch Repair-Deficient/Microsatellite Instability-High (MSI-H), the data on neoadjuvant setting is limited. Methods: In this retrospective study, we enrolled eight patients with advanced MSI-H colorectal cancer from three hospitals. four patients are locally advanced and four are metastatic. All the patients received at least two doses of PD-1 antibody with or without chemotherapy as neoadjuvant therapy. The aim of the present study was to evaluate the short‐term efficacy and toxicities of this strategy. Results: Neoadjuvant PD-1 Blockade is well tolerated with a few immune-related side-effect profiles. All the enrolled patients had a major response in imaging and/or pathological evaluation. Five of the seven resected patients were evaluated as pathological complete response. One patient without surgery has a cCR tumor response. For the patients with radical surgery, there is no surgery-related complication observed. Conclusions: Neoadjuvant PD-1 blockade induced tumor regression with a major clinical and pathological response in advanced dMMR/MSI-H colorectal cancer. Further studies are required to evaluate the long-term effect of this strategy.