Bottom line: Rectal bleeding and abdominal pain are common (more than 40% of patients studied) symptoms; weight loss, diarrhea, constipation, and/or weight loss can be present in 25% of patients. Hemoglobin < 12 g/dl can occur in about 25% of patients, while positive fecal occult blood test result is less common.
Summary: Hamilton W, et al. Clinical features of colorectal cancer before diagnosis: a population-based case-control study. Br J Cancer. 2005 Aug 22;93(4):399-405.
Population-based case-control study of patients (n=379) age 40+ diagnosed with primary colorectal cancer 1998-2002 in a community. Each case matched to 5 controls. Reviewed records for symptoms and test results during 2 years prior to diagnosis. RESULTS:Table 2 summarizes rates of various symptoms and test results for the cases and the controls.