title: Increased plasma DNA integrity index in head and neck cancer patients.
abstract: Analysis of the length of circulating DNA in plasma has been reported as a marker for solid tumor detection. We assessed the sensitivity and specificity of increased plasma DNA length to identify patients with head and neck squamous cell carcinoma (HNSCC) and monitor posttreatment disease status. Fifty-eight HNSCC patients with paired pre- and postoperative plasma and 47 plasma samples from control subjects were analyzed using quantitative PCR to determine plasma DNA integrity index. We found that the mean DNA integrity index was significantly greater in the plasma from HNSCC patients, 0.24 (95% CI: 0.11, 0.38), when compared to plasma from the control subjects, -2.24 (95% CI: -2.92, -1.56), p < 0.0001 using multivariate analysis. The optimal sensitivity (the value for which sensitivity equals specificity) was found at a plasma DNA integrity index of 0.82: sensitivity, 84.5%; specificity, 83%. However, there was no significant difference noted between pre- and postoperative DNA integrity index in plasma samples from HNSCC patients. This study shows that DNA integrity index in the plasma of the patients with HNSCC is increased in comparison with that in the plasma from non-HNSCC control subjects. Lack of normalization of plasma DNA integrity index after surgical resection implies the persistence of a population of cells with an altered pattern of DNA degradation despite removal of malignancy.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Head and Neck Cancer Research Division, Johns Hopkins Medical Institutions, Baltimore, MA, USA. jcalifa@jhmi.edu
authors.forename: Wei-Wen
authors.initials: WW
authors.lastname: Jiang
authors.forename: Marianna
authors.initials: M
authors.lastname: Zahurak
authors.forename: David
authors.initials: D
authors.lastname: Goldenberg
authors.forename: Yelena
authors.initials: Y
authors.lastname: Milman
authors.forename: Hannah Lui
authors.initials: HL
authors.lastname: Park
authors.forename: William H
authors.initials: WH
authors.lastname: Westra
authors.forename: Wayne
authors.initials: W
authors.lastname: Koch
authors.forename: David
authors.initials: D
authors.lastname: Sidransky
authors.forename: Joseph
authors.initials: J
authors.lastname: Califano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000235:genetics* / Q000532:radiotherapy / Q000601:surgery; D017931:DNA Primers; D004273:DNA, Neoplasm / Q000097:blood*; D006258:Head and Neck Neoplasms / Q000097:blood / Q000235:genetics* / Q000532:radiotherapy / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D017931:DNA Primers; D004273:DNA, Neoplasm