Blood group A and gastric cancer risk in the Hospital Universitario de Santander (Bucaramanga, Colombia)

Abstract

Objective: to determine the association between blood group A and gastric cancer.

Patients and methods: a study of cases and controls was performed; the patients had gastric cancer confirmed by histopathology, were taken care of in the oncology unit of the Hospital Universitario de Santander between january 2001 and december 2005, living in Bucaramanga and in the influence area of the institution; the controls were patients admitted in the hospital in the general internal medicine service due to medical causes different from gastric cancer and patients in the gastroenterology unit who were subject to upper gastrointestinal tract endoscopy with normal results. Those patients from whom there was no information or those that did not wish to participate were excluded. The data were taken from the clinical histories or by telephone if more details were needed. A data base was built on Microsoft Access 2003, and later on they were analyzed using the Stata 9.0 software.

Results: 208 clinical histories of patients with cancer were reviewed of which 153 met the inclusion criteria and the information was complete. The prevalence of the different blood groups in the population studied was: 56.74% for group O, 32.17% for group A, 10.22% for group B and 0.87% for group AB. A statistically significant association was found between gastric cancer in blood group A showing an RO = 2.22 (IC 95%: 1.38-3.57); an association was found between gastric cancer and first consanguinity family members with a different type of cancer, RO =1.91 (CI 95%: 1.05-3.46). Besides the above, the logistic regression multivariable analysis showed that being less than 50 years old reduced the risk of cancer (RO = 0.44, CI 95%: 0.26-0.77). No association was found between eating habits such as fruits and vegetables, cereals, coffee, corn bread from Santander, processed meats, salty food and hot pepper with the onset of gastric cancer. The predominant cancer type was adenocarcinoma, intestinal variety with 45.75% and the anthral - pyloric location with 43.14%. The proportion of Helicobacter pylori reported by pathology was 30.07%.