Open AccessTumor‐associated DNA mutation detection in individuals undergoing colonoscopy
Author(s) -
Fleshner Phillip,
Braunstein Glenn D.,
Ovsepyan Gayane,
Tonozzi Theresa R.,
Kammesheidt Anja
Publication year - 2018
Publication title -
cancer medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 53
ISSN - 2045-7634
DOI - 10.1002/cam4.1249
Subject(s) - colonoscopy , colorectal cancer , medicine , germline mutation , somatic cell , dna , mutation , cancer , gastroenterology , pathology , cancer research , gene , biology , genetics
The majority of colorectal cancers ( CRC ) harbor somatic mutations and epigenetic modifications in the tumor tissue, and some of these mutations can be detected in plasma as circulating tumor DNA (ct DNA ). Precancerous colorectal lesions also contain many of these same mutations. This study examined plasma for ct DNA from patients undergoing a screening or diagnostic colonoscopy to determine the sensitivity and specificity of the ct DNA panel for detecting CRC and precancerous lesions. Two hundred patients without a history of nonskin cancer had blood drawn before a colonoscopy. Plasma ct DNA was measured with a 96 mutation panel for nine cancer driver genes. The ct DNA results were correlated with the findings at colonoscopy. Of the 200 patients, 176 (88%) had wild‐type DNA , 12 (6%) had mutations detected, and 12 (6%) had indeterminate results. Colonoscopy was normal in 80% of the patients and 20% were found to have polyps. No CRC was found in this study, precluding a determination of true‐positive rate for CRC detection. Our ct DNA panel was positive in 13.2% of patients with colonic polyps found at colonoscopy, while 4.7% of patients with normal colonoscopy also had ct DNA detected, which may represent ct DNA released from a benign process, an occult tumor, or an acquired somatic mutation from clonal hematopoiesis.