Microsatellite Instability Correlated Inflammatory Markers and their Prognostic Value in the Rectal Cancer Following Neoadjuvant Chemoradiotherapy: A Hypothesis-generating Study.

Abstract

This study aimed to analyze the correlation between microsatellite instability (MSI) and inflammatory markers during neoadjuvant CRT in rectal cancer and its influence on prognosis. A total of 549 patients with locally advanced rectal cancer underwent neoadjuvant CRT. Complete blood counts before CRT, and 4-8 weeks after CRT were used to measure neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). MSI was significantly associated with elevated NLR and PLR after CRT as well as with a change in NLR and PLR during CRT. Neither inflammatory markers nor MSI significantly related to survival. However, in patients with MSI, an increase in NLR and PLR before CRT was significantly correlated with poor overall survival and disease-free survival. There is correlation between inflammatory markers and MSI during CRT and it influences prognosis. Therefore, inflammatory markers might have a role in assessing the microenvironment related to MSI and the immunologic response in rectal cancer.