bowel polyps or cancer

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A. Karlin et al.: Fecal Skatole and Indole and Breath Methane and Hydrogen in Patients with Large Bowel Polyps or Cancer and analysis procedures. Skatole and indole external standards were made up to a known concentration in methylenedichloride. Extracts were analyzed for skatole and indole content on a gas chromatograph equipped with a 6 ft x 1/4 in. OD x 2 mm ID glass column packed with 3% OV-17 (R) liquid phase on 80/100 mesh Anakrom Q (Supelco, Bellefonte, Pa). The operating conditions were as follows: 40 cc nitrogen/min carrier gas, injector temperature 185 ~ and hydrogen flame ionization-detector temperature 185 ~ Skatole and indole were identified and quantified by comparison of retention time and peak areas with those of the standards (Elsden et al. 1976; Mackenzie 1977). Under these conditions 92%-94% of the skatole and indole internal standards were extracted and analyzed. Fecal skatole and indole concentrations were calculated on the basis of dry weight.
* Supported by PuNic Health Service Gra~at CA-29056 from the National Cancer Institute Offprint requests to: D.A. Karlin, Temple University School of Medicine, Department of Medicine, Gastroenterology Section, Philadelphia, PA 19140, USA
Summary. The object of this study was to explore the use of fecal skatole and indole and breath methane and hydrogen as metabolic markers of the anaerobic colonic flora in patients with unresected large bowel cancer or polyps. Patients with descending or sigmoid colon cancer were more likely to be breath methane excretors than control subjects, patients with proximal colon cancer, and patients with rectal cancer. Control subjects excreting breath methane excreted less fecal skatole than breath methane excretors in the following groups: patients with adenomatous polyps, all patients with colorectal cancer, patients with proximal colon cancer, patients with descending and sigmoid colon cancer, and patients with rectal cancer. These data suggest that fecal skatole excretion equal to or greater than 100 gg/g feces might be useful to discriminate colorectal cancer patients from control subjects. Twenty-nine percent (8 of 28) of the cancer patients had both "high" skatole levels and breath methane excretion compared with only 2% (1 of 41) of the control subjects (P < 0.01). Key words: Colorectal cancer - Bacterial metabolites.
D.A. Karlin, A.J. Mastromarino, R.D. Jones, J.R. Stroehlein, and O. Lorentz
Department of Medicine, Gastroenterology Section, The University of Texas System Cancer Center, M.D. Anderson Hospital and Tumor Institute, Houston,பைடு நூலகம்TX 77030, USA
Introduction
Large bowel cancer is a major health problem in the United States and other industrialized countries. In 1984 there will be an estimated 130,000 new cases with almost half of the individuals eventually dying from the disease (American Cancer Society 1984). Because
the etiology is unknown, primary prevention of the disease is not possible now. Therefore secondary prevention, the detection and treatment of premalignant conditions or cancer in an early stage amenable to surgical cure is the goal of current research efforts directed at population screening. Studies using proctosigmoidoscopy and fecal occult blood testing in asymptomatic individuals indicate that these techniques may potentially reduce the morbidity and mortality of colorectal cancer in populations (Winawer et al. 1980; Sherlock et al. 1980). Selection of groups for screening is currently based on age. To enhance the cost effectiveness of screening, improved techniques must be developed for multifactorial screening of large populations to select subgroups that are at increased risk for developing large bowel cancer. Although the colonic microflora has been suggested as playing a role in the etiology of coIorectal cancer, significant differences in its composition have been difficult to demonstrate. However, the functional, metabolic activities of the fecal flora do seem to be significantly different among various populations studied (Hill et al. 1975; Mastromarino et al. 1976; Reddy et al. 1977 a; Reddy and Wynder 1977 b). Skatole, indole, methane, and hydrogen are end products of anaerobic metabolism of the colonic flora. Breath methane content has been studied in patients with carcinoma of the large bowel. A prospective study found that 80% of 30 patients with unresected colorectal cancer excreted over one part per million (ppm) breath methane compared with 40% of 272 control subjects. (Haines et al. 1977). A retrospective study demonstrated that 13 patients with unresected descending or sigmoid colon cancers were almost twice as likely to be breath methane excretors as 38 patients with colorectal cancer at other sites (Karlin et al. 1982). The objective of our study was to expand our investigation of breath methane excretion and explore the use of skatole, indole, and hydrogen as additional