Low frequency of human T-cell lymphotropic virus 1 antibodies in Iranian gastric cancer patients in comparison to controls.

There is some evidence that human T-cell lymphotropic virus (HTLV-1) infection has a reverse association with gastric cancer (GC). Data about this association in the Iranian population are scarce. In this study we therefore assessed the frequency of anti-HTLV-1 antibody in GC patients and compare it to antibody presence in healthy individuals in Iranian population. This case control study was performed between 2008-2011 on 201 GC patients and 219 control subjects. HTLV-1 antibodies were assessed by ELISA and the positive results were confirmed by western blotting. Totals of 201 gastric cancer patients and 219 controls were enrolled in this study. The tumors in the majority of patients (45.3%) were in the distal (non-cardia) area. Mean age of patients at the time of diagnosis was 59.2±12.5 and mean age of controls was 57.7±11.3. While only one GC patient (0.5%) was positive for HTLV-1 antibody, there were four individuals (1.89%) from the control group with antibodies. In addition, smoking had statistically significant relationship with cancer (P=0.001). Our study showed that the frequency of HTLV-1 antibody in patients was lower than in controls, similar to the results obtained in Japan. Further investigations with a larger sample size are needed in order to determine the association between GC and HTLV-1 infection in Iran.