Detect Microsatellite Instability Status in Blood Sample of Advanced Colorectal Cancer Patients by Next-Generation Sequencing

Detect Microsatellite Instability Status in Blood Sample of Advanced Colorectal Cancer Patients by Next-Generation Sequencing

The method to analyze the microsatellite instability (MSI) status by next-generation sequencing (NGS) has been established to assess the deficiency of DNA mismatch repair (MMR) system. The aim of our study is to evaluate the feasibility and reliability of this NGS method by testing the circulating tumor DNA (ctDNA) in blood sample of advanced colorectal cancer patients. If the result is positive, the MSI status could be easily learned without the acquisition of tissue samples.

Inclusion Criteria:

• a biopsy proven histological diagnosis of colorectal carcinoma
• MSI status of tissue sample known by IHC or PCR method
• willing to participate and informed consent signed

Exclusion Criteria:

• history of other malignant tumors
• patients with inflammatory bowel disease
• patients with familial adenomatous polyposis
• patients treated by surgery or adjuvant treatment
• pregnant or lactating women