DNA polymerase-alpha as a putative early relapse marker in non-small cell lung cancer. An immunohistochemical study.

The authors examined 72 fresh frozen sections of primary lung cancer using a monoclonal antibody for DNA polymerase-alpha (POL-alpha). The percentage of POL-alpha-positive cells was 17.3%. The tumors were divided into two groups. In one group, more than 5% of the POL-alpha-positive cells were designed POL-alpha-positive, and in the other group less than 5% were POL-alpha-negative. The incidence of POL-alpha-positive in men was statistically higher than that in women (P less than 0.05). The incidence correlated with the T (tumor) status, with a significance. Based on data on 43 patients with non-small cell lung cancer and who underwent a complete resection, the 3-year disease-free survival rates of POL-alpha-positive and POL-alpha-negative cells were 42% and 81%, respectively (P less than 0.05). When the patients were restricted to the class of N0 disease or Stage I, all the patients diagnosed as a cases of a relapse of lung cancer were POL-alpha positive. The 3-year disease-free survival rate of patients with POL-alpha negative was 100%. Our data suggest that in cases of non-small cell lung cancer, POL-alpha expression is associated with the extent of malignancy and a recurrence. Thus POL-alpha may prove to be a pertinent marker of an early relapse.