Correlation Between Clinicopathological Features and , , and Mutation Status in Chinese Colorectal Cancer Patients

This study was retrospectively performed to analyze correlations between clinicopathological features of colorectal cancer (CRC) and mutations in , , and in Chinese patients, and to assess the importance of detecting additional mutations in exons 3 and 4 and in patients with CRC. ( and ) and mutations were detected in 715 and 655 patients respectively. The mutation rate of ( or ) was 45.6% (326/715). exon 2 mutations were evaluated in 36.6% of patients (262/715). Additional mutations in exons occurred in 9.0% of patients (64/715), including exons 3 and 4 in 5.6% (40/715) and exons 2, 3, or 4 in 3.4% (24/715). Among 453 patients with wild-type exon 2, 14.1% (64/453) had other mutations in exons. The most frequent sites of mutations were codons 12, 13, 61, and 146 in and codons 12 and 61 in . The mutation rate of (exon 15) was 4.0% (26/655), and the most frequent mutation site was codon 600. Among 440 patients with CRC who had a primary tumor resection at our center, those with mucinous or signet ring cell CRC were more likely to harbor mutations than those with adenocarcinoma (62.7% vs. 43.6%, P=0.006 and 59.3% vs. 39.6%, P=0.004, respectively). Female patients had a higher (exon 15) mutation rate than male patients (5.1% vs. 1.1%, P=0.017). Detection of both and mutations is useful for selecting patients who will benefit from anti-EGFR monoclonal antibody therapy. mutations were more frequent in patients with mucinous adenocarcinoma/signet ring cell CRC, whereas mutations were more common in female patients with CRC.