Frequency and determinants of disagreement and error in gleason scores: a population-based study of prostate cancer.

Background: To examine factors that affect accuracy and reliability of prostate cancer grade we compared Gleason scores documented in pathology reports and those assigned by urologic pathologists in a population-based study.

Methods: A stratified random sample of 318 prostate cancer cases was selected to ensure representation of whites and African-Americans and to include facilities of various types. The slides borrowed from reporting facilities were scanned and the resulting digital images were re-reviewed by two urologic pathologists.

MutL-homolog 1 expression and risk of incident, sporadic colorectal adenoma: search for prospective biomarkers of risk for colorectal cancer.

To characterize the expression of the mismatch repair gene MutL-homolog 1 (MLH1) in normal colorectal crypts in humans, and assess parameters of its expression as a potential biomarker of risk for colorectal neoplasms, we conducted a pilot, colonoscopy-based case-control study (51 cases, 154 controls) of incident, sporadic colorectal adenoma. Biopsies of normal-appearing rectal, sigmoid, and ascending colon mucosa were procured, immunohistochemically processed for MLH1 protein, and analyzed using custom quantitative image analysis procedures. MLH1 expression in the ascending colon was, on average, 49% proportionally lower in cases than controls (P = 0.

Effects of vitamin D and calcium supplementation on markers of apoptosis in normal colon mucosa: a randomized, double-blind, placebo-controlled clinical trial.

To further clarify and/or develop calcium and vitamin D as chemopreventive agents against colorectal cancer in humans, understand the mechanisms by which these agents reduce risk for the disease, and develop "treatable" biomarkers of risk for colorectal cancer, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 x 2 factorial clinical trial to test the effects of calcium and vitamin D3, alone and in combination on markers of apoptosis, in the normal colorectal mucosa. Ninety-two men and women with at least one pathology-confirmed colorectal adenoma were treated with 2.0 g/d calcium or 800 IU/d vitamin D3, alone or in combination, versus placebo over 6 months.

Detecting and quantifying biomarkers of risk for colorectal cancer using quantum dots and novel image analysis algorithms.

Colorectal cancer, the second leading cause of cancer deaths in the United States, is a molecular disease that is largely lifestyle determined and preventable. While heart disease has been sharply declining, in large part from widespread use of biological measurements that indicate risk ("biomarkers of risk"), such as blood cholesterol, to motivate and guide preventive treatment, colorectal cancer is a disease for which mortality rates have changed little and for which there have been no biomarkers of risk. Based on new knowledge about the molecular basis of colorectal cancer we developed and validated a panel of treatable biomarkers of risk that can be measured in rectal biopsies using automated immunohistochemistry and semi-automated image analysis.