International Journal of Colorectal Disease

, Volume 26, Issue 5, pp 583–592

A simplified, non-invasive fecal-based DNA integrity assay and iFOBT for colorectal cancer detection

  • Murugan Kalimutho
  • Giovanna Del Vecchio Blanco
  • Micaela Cretella
  • Elena Mannisi
  • Pierpaolo Sileri
  • Amanda Formosa
  • Francesco Pallone
  • Giorgio Federici
  • Sergio Bernardini
Original Article

DOI: 10.1007/s00384-010-1128-x

Cite this article as:
Kalimutho, M., Del Vecchio Blanco, G., Cretella, M. et al. Int J Colorectal Dis (2011) 26: 583. doi:10.1007/s00384-010-1128-x

Abstract

Purpose

Neoplasia cells exfoliated from colorectal epithelium have dysfunctional apoptotic mechanisms, thus it is possible to identify high-molecular weight DNA fragments in feces. This prospective single-center study was performed to evaluate the sensitivity and specificity of fecal-based DNA integrity versus immunological fecal occult blood test (iFOBT) and calprotectin for colorectal cancer (CRC) and adenoma detection.

Methods

Feces were collected from 204 subjects and DNA integrity was quantified by quantitative-denaturing high performance liquid chromatography (QdHPLC). Calprotectin and iFOBT were assessed using commercial kits. The diagnostic performance was calculated by receiver operating characteristic (ROC) curves analysis.

Results

A total of 192 fecal specimens were analyzed and 12 samples were excluded due to DNA degradation. We found long DNA (L-DNA) occurrence in feces with a sensitivity of 86% (n = 24/28) and a specificity of 81% for CRC detection. To minimize false-positive cases of the developed test, area under the curve of ROC was evaluated such that the specificity was increased to 92% with decreased sensitivity to 79%, p = 0.0001 for CRC detection. iFOBT was positive in 51% (n = 14/27) while calprotectin was positive in 75% (n = 18/27). The combination of iFOBT and L-DNA identified a greater number of CRC cases with a sensitivity of 89% and a specificity of 95%, p < 0.001. The combination also improved the sensitivity of polyps, particularly high-grade dysplasia and advanced adenoma (33%, p = 0.0015) as opposed to a single evaluation assay (17–21%).

Conclusions

This study illustrates the usefulness of fecal DNA integrity assay by QdHPLC as a non-invasive, easy-to-perform, and reproducible method with a high level of sensitivity in detecting individuals with colorectal neoplasia. Combination of iFOBT and L-DNA improves the sensitivity for CRC and adenoma detection.

Keywords

CRCDIAFecesiFOBTL-DNAQdHPLC-DIA

Abbreviations

CRC

Colorectal cancer

FOBT

Fecal occult blood test

gFOBT

Guaic FOBT

iFOBT

Immunochemical FOBT

fDNA

Fecal DNA

DIA

DNA integrity assay

L-DNA

Long DNA

QdHPLC

Quantitative denaturing high performance liquid chromatography

AVG-DIA

Average DIA

ROC

Receiver operating characteristic

Supplementary material

384_2010_1128_MOESM1_ESM.xls (21 kb)
Table S1Demographic and clinical characteristic of CRC patients together with the ratio of long DNA by Q-dHPLC, iFOBT, and calprotection results (XLS 21 kb).

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Murugan Kalimutho
    • 1
    • 4
  • Giovanna Del Vecchio Blanco
    • 1
    • 3
  • Micaela Cretella
    • 3
  • Elena Mannisi
    • 3
  • Pierpaolo Sileri
    • 3
  • Amanda Formosa
    • 1
  • Francesco Pallone
    • 1
    • 3
  • Giorgio Federici
    • 1
    • 2
  • Sergio Bernardini
    • 1
    • 2
  1. 1.Department of Internal MedicineUniversity of Rome “Tor Vergata”RomeItaly
  2. 2.Department of Laboratory Medicine,“U.O.C. Clinical Molecular Biology and Biochemistry”University Hospital Tor VergataRomeItaly
  3. 3.Gastroenterology UnitUniversity Hospital Tor VergataRomeItaly
  4. 4.Centre for Cancer Research and Cell Biology (CCRCB)Queen’s UniversityBelfastUK