Background. In recent years numerous reports have discussed the relati
onship between the human leukocyte antigen and lung cancer. However, t
he genetic background of lung cancer has not yet been precisely clarif
ied. Methods. To investigate the genetic background of lung cancer, th
e human leukocyte antigens in 159 normal healthy control subjects and
102 lung cancer patients were studied, and restriction fragment length
polymorphism analysis of the tumor necrosis factor (TNF) beta gene in
165 normal healthy control subjects and 135 lung cancer patients was
performed. Results. Lung cancer patients showed a high frequency of hu
man leukocyte antigen B61; however, no statistical difference was foun
d. In the lung cancer patients, the TNF beta 10.5/10.5-kb allele was f
ound at a low frequency, 38.5%, compared to 53.3% in normal controls (
chi(2) = 7.51, P = 0.011, corrected P = 0.033, relative risk = 0.77).
In the relationship between the histologic types and the TNF beta gene
, the TNF beta 10.5/10.5-kb allele showed low frequencies: 38.5% in ad
enocarcinoma, 38.2% in squamous cell carcinoma, and 27.8% in small cel
l carcinoma, although no statistical difference was shown. In relation
to the postoperative survival period, the TNF beta 10.5/10.5kb allele
was associated with prolonged survival. Conclusions. The TNF beta 10.
5/10.5-kb allele may be associated with resistance to lung cancer and
with a better prognosis.