XXXX : a reassessment of prognostic factors following modification of radiotherapy.

@entity1 @entity978 @entity5 @entity66
Between 1970 and 1982, 175 @entity1 with Stage IA, B, IIA, B, or IIIA @entity978 were treated with curative radiotherapy following surgical @entity5 . The @entity1 treated prior to 1975 received either regular extended or total nodal field treatments (Treatment Group 1, N = 65). Unsatisfactory results from this treatment program led to treatment modification in 1975. The modified protocols consisted of low-dose lung irradiation in @entity1 having large mediastinal masses and/or @entity66 , and low-dose liver irradiation for Stage IIIAS+ @entity1 (Treatment Group 2, N = 110). Recurrence-free survival rates improved significantly for various risk groups. Univariate analysis indicated that age, stage, symptoms, mediastinal mass size, number of sites involved, @entity66 , stage, and symptoms were significant risk factors in Treatment Group 1. In Treatment Group 2, only sex was a statistically significant risk factor. Stepwise Cox regression analysis for risk factors selected mediastinal mass size and stage as the most significant prognostic factors in Treatment Group 1. In Treatment Group 2, number of initial disease sites and sex were the most significant risk factors. The results of the study show significant improvement in recurrence-free survival rates in Treatment Group 2. It is concluded that these improvements are due to the modification in treatment.
