The prevalence of iron deficiency anemia and its clinical implications in patients with colorectal carcinoma

Background: Gastrointestinal (GI) tract malignancy is an important cause of chronic iron deficiency anemia (IDA). The present study was designed to determine the prevalence of IDA and its clinical implications in colorectal cancer patients. Methods: We performed a retrospective study of 101 patients who were admitted to Taipei Veterans General Hospital with proven colorectal carcinoma from 2003-2005. We reviewed the discharge charts and recorded the following data: gender, age, tumor size, tumor site, tumor stage, clinical symptoms, complete blood counts, serum iron (SI), total iron binding capacity (TIBC), serum ferritin, lactate dehydrogenase (LDH) and carcinoembryonic antigen (CEA). The patients were divided into 2 groups: 1 with and the other without anemia. Different variables of the 2 groups were compared and analyzed to find out the risk factors of anemia in patients with colorectal cancer. Results: A total of 101 patients, with a mean age of 65.3 years, were enrolled; 56 were male. Their mean hemoglobin was 11.8g/dL. Fifty-one patients (51%) were found to have anemia. Multivariate logistic regression analysis showed that female gender, tumor in the right colon (cecum, ascending colon, hepatic flexure), and maximum tumor diameter >= 3 cm were risk factors of anemia in patients with colon carcinoma. Serum ferritin had been measured in 25 patients, and low ferritin level (< 40 mu g/L) was found in 15 (60%) of them. CEA and LDH were elevated in 45% (43/95) and 46% (43/93) of patients with colorectal cancer, respectively. Conclusion: Iron deficiency anemia is a common clinical manifestation of patients with colorectal carcinoma, and occurred more frequently in females, patients with right colon tumor and with larger tumor size.