The prevalence of KRAS mutation in colorectal cancer patients in Iranian population: A systematic review and meta-analysis study

Colorectal cancer (CRC) is one of the most common cancers in the World that KRAS mutations are considered as a key step in the progression of CRC. This meta-analysis study aimed to evaluate the prevalence of KRAS mutations in CRC patients in Iran. Six online databases including PubMed, Science direct, Scopus, Web of science, Cochran Library, and Scientific Information Database (SID) were searched systematically up to January 2017. A random-effects meta-analysis was used to calculate the estimation of the prevalence of KRAS mutations in CRC patients by the event rate (ER) with 95% confidence interval (95%CI). Out of 82 articles identified from the search, eleven studies included and analyzed for meta-analysis study. The studies included 1814 CRC patients that mean age of the patients was 57.5 years. The pooled ER of the studies for estimation of the prevalence of KRAS mutation in CRC patients was 32.8% (95%CI=28.7-37.3%). The pooled ER of the studies for the prevalence of codon 12 mutation was 72.5% (95%CI=59.8-82.3%) and for codon 13 mutation was 20% (95%CI=14.6-26.7%). The results showed that the prevalence of KRAS mutation in Iran was different with more studies that therefore the geographical area and race can impact on the prevalence of KRAS mutation in CRC patients. Also, codon 12 had the most prevalence among mutant codons, followed by codon 13 that Gly to Asp and Gly to Val were the most mutations in codon 12.   Peer Review Details Peer review method: Single-Blind (Peer-reviewers: 02) Peer-review policy Plagiarism software screening?: Yes Date of Original Submission: 07 September 2017 Date accepted: 02 October 2017 Peer reviewers approved by: Dr. Lili Hami Editor who approved publication: Dr. Phuc Van Pham