Background: In NcoI restriction fragment length polymorphism analysis of tumor necrosis factor-beta (TNF-beta) gene, the frequency of 10.5-kb homozygote is low in patients with lung cancer and is associated with a better prognosis. These results should be examined in other malignancies.
Methods: Using polymerase chain reaction, the authors performed NcoI restriction fragment length polymorphism analysis in 152 patients with gastric cancer, in 69 patients with benign gastric lesion, and in 141 healthy volunteers.
Results: In 3-year survival, the 10.5-kb homozygote showed a better prognosis (87.1%) than other alleles (5.5-kb homozygote, 52.5%; heterozygote, 79.1%), and there was a statistically significant difference between the 10.5-kb homozygote and the 5.5-kb homozygote. In 3-year survival for Stages III and IV, the 10.5-kb homozygote also showed a better prognosis (64.9%) than other alleles (5.5-kb homozygote, 16.7%; heterozygote, 41.4%). There were statistically significant differences (10.5-kb homozygote vs. 5.5-kb homozygote, P < 0.01; heterozygote vs. 5.5-kb homozygote, P < 0.05). There was a statistical difference between all patients and Stages III and IV (P < 0.05).
Conclusions: The 10.5-kb homozygote of TNF-beta gene is associated with a prolonged survival in patients with gastric cancer, as has been shown in the patients with lung cancer.