182P - Clinical Implementation of the Universal Tumor Screening with the Mismatch Repair (MMR) Proteins on Decision Impact of Adjuvant Chemotherapy in Pat...

Date 18 November 2017
Event ESMO Asia 2017 Congress
Session Poster lunch
Topics Colon Cancer
Rectal Cancer
Gastrointestinal Cancers
Personalised Medicine
Presenter Yasuaki Yamamoto
Citation Annals of Oncology (2017) 28 (suppl_10): x42-x56. 10.1093/annonc/mdx659
Authors Y. Yamamoto1, Y. Tsukada1, H. Bando2, T. Sasaki1, Y. Nishizawa1, M. Kojima3, T. Kuwata3, M. Ito1, T. Yoshino2
  • 1Department Of Colorectal And Pelvic Surgery, National Cancer Center Hospital East, 277-8577 - Kashiwa/JP
  • 2Department Of Gastroenterology And Gastrointestinal Oncology, National Cancer Center Hospital East, 277-8577 - Kashiwa/JP
  • 3Division Of Pathology, National Cancer Center Hospital East, 277-8577 - Kashiwa/JP



For patients (pts) with pathological stage II/III CRC, tumors with MMR deficient (dMMR), of which testing is to detect the expression of MMR proteins (MLH1, MSH2, MSH6, and PMS2) in tumor tissue using immunohistochemistry (IHC), are associated with a lack of benefit from fluoropyrimidine monotherapy in an adjuvant setting. However, the frequency and clinical implementation of detecting dMMR in Asian CRC pts has not been well investigated.


The purpose of this study is to investigate the frequency of dMMR in pts with Stage II/III CRC in Japan and to elucidate clinical implementation on the decision impact of adjuvant chemotherapy.


From March 2016 to May 2017, the MMR status for 173 Stage II/III CRC pts as the Universal Tumor Screening was retrospectively investigated, out of which 168 pts were pathologically diagnosed as Stage II/III. Of the 168 pts, 14 (8.3%) were described as dMMR, while 154 (91.7%) were as MMR proficient (pMMR). Of the 14 dMMR pts, six (43%) didn’t meet the revised Bethesda guideline. The frequencies of dMMR according to the primary tumor location were 10/37 (27%) in right-sided colon, 0/44 (0%) in the left-sided colon, and 4/87 (5%) in rectum, respectively. The patterns of dMMR were as follows: loss of MLH1 and PMS2 in 11 pts, loss of MSH2 and MSH6 in two, and loss of MSH2 alone in one. Of the 14 dMMR pts, 9 (64%) received oxaliplatin-based chemotherapy and 4 (29%) received no adjuvant chemotherapy primarily due to comorbidity, while only one (7%) patient received fluoropyrimidine monotherapy by pt’s request.


The frequency of dMMR in Japanese stage II/III CRC pts were consistent with the previous reports. By assessing the MMR status for all Stage II/III CRC pts, the optimization of the regimen as adjuvant chemotherapy for dMMR pts might be suggested.

Clinical trial identification

Legal entity responsible for the study

Yasuaki Yamamoto




All authors have declared no conflicts of interest.