LONG-TERM SURVIVORS OF NONSMALL CELL LUNG-CANCER AFTER RADIATION-THERAPY - THE SIGNIFICANCE OF HISTOLOGICAL TYPE

To determine if histological type was a prognostic factor for non-smal l cell lung cancer (NSCLC), 67 two-year survivors were analyzed retros pectively after definitive radiation therapy (RT) for inoperable or un resectable Stage I-III NSCLC. There was no difference in short-term ou tcome (within 2 years) between patients with squamous cell carcinoma a nd patients with adenocarcinoma. After 2 years, the 5-year survival ra te for the 2-year survivors was 56% for squamous cell carcinoma (n=55) and 34% for adenocarcinoma (n=12). According to degree of histologic differentiation, patients with poorly differentiated adenocarcinoma ha d a poorer outcome compared than those with well differentiated adenoc arcinoma and squamous cell carcinoma as a whole. Among progression-fi ee patients at the end of 2 years, 97% of patients with squamous cell carcinoma survived without evidence of disease for more than 5 years. Disease-free 2-year survival should be substituted for 5-year survival in patients with squamous cell carcinoma treated with RT.