Improved survival of patients with unresectable non-small-cell bronchogenic carcinoma by an innovated high-dose en-bloc radiotherapeutic approach.

From 1972 to 1977, 162 patients were treated with definitive radiotherapy for the underlying unresectable non-small-cell bronchogenic carcinoma by a radiotherapeutic technique that had sequentially evolved from a low-dose (40-45 gray) small-volume approach (AP-PA POP) to a high-dose (60-64 gray) large-volume en-bloc approach (AP-PA POP plus AP-RPO-LPO) which included the primary tumor and the entire regional lymphatics including both supraclavicular areas. Median survival and short-term survival up to 1.5 years were independent of radiation doses (40-64 gray) and target volumes studies. However, long-term survival greater than or equal to 2 years was radiation-dose and target-volume dependent: actuarial survival 36% and 28% vs. 10% and 3% for the high-dose (60-64 gray) en-bloc approach vs. low-dose (40-45 gray) small-volume radiotherapy at 2 and 3 years, respectively, with a minimum follow-up of 2 years, P less than 0.05. Actuarial five-year survival rate 7.5% was obtained with radiation dose greater than or equal to 50 gray. However, there was no five-year survivor among patients who were treated with radiation dose less than 50 gray. Local tumor control is radiation-dose dependent: local tumor control rates at greater than or equal to 18 months were 76% vs. 29% by 56-64 gray vs. 40-49 gray, respectively, P less than 0.05. The patterns of failure appeared to be tumor-histology dependent; for squamous cell carcinoma, the primary and regional lymphatic areas are the most common sites of failure, and for adenocarcinoma, it is the brain or bone. The high-dose en-bloc radiotherapy has been very well tolerated; 5% (4/80) incidence of symptomatic pneumonitis has been observed.