Clinical relevance of Lgr5 expression in colorectal cancer patients

Kim, Young Joo; Kang, Dong Hyun; Song, Geum Jong; Ahn, Tae Sung; Son, Myoung Won; Lee, Moon Soo; Baek, Moo Jun

Abstract

PURPOSE
Lgr5 is a well-known stem cell marker in colorectal cancer (CRC). This retrospective study evaluated the expressions of Lgr5 in CRC specimens, and examined whether these expressions were associated with survival outcomes.
METHODS
We used immunohistochemistry to retrospectively examine expressions of Lgr5 in paraffin-embedded specimens from 337 patients with CRC between January 2009 and December 2013. All clinicopathologic data were collected by retrospective review based on medical records. The correlation between its expression and clinicopathological data as well as clinical outcomes of patients was analyzed.
RESULTS
Low expression and high expression of Lgr5 in 337 patients were 175 (51.9%) and 162 (48.1%), respectively. There was no statistically significant difference in the association of Lgr5 expression with clinicopathologic factors (age, tumor location, lymphatic invasion, vascular invasion, perineural invasion, TNM stage, and differentiation). In the survival analysis, the high expression group of Lgr5 showed a better prognosis than the low expression group in disease-free survival (P=0.044). However, overall survival was not significantly different between the two groups (P=0.087). In multivariate analysis, we found that high expression of Lgr5 was independent prognostic factor for tumor relapse (hazard ratio, 0.601; 95% confidence interval, 0.388-0.929; P=0.022).
CONCLUSION
In present study, high expression of Lgr5 is an independent predictor of favorable prognosis in patients with CRC. So, further well designed, prospective, large scale studies are needed to examine the value of Lgr5 as a prognostic biomarker for CRC.