Preoperative radiation therapy in regionally localized stage III non-small cell lung carcinoma: long-term results and patterns of failure.

Seventy-four patients from January 1975 through December 1982, with clinical Stage III Mo non-small cell carcinoma of the lung were treated at our Medical Center with a course of pre-operative radiation therapy to be followed by surgical resection. Radiation therapy consisted of delivering a total dose of 40 Gy with 200 cGy per fraction over a period of 4 weeks to the primary tumor in the lung and the regional lymph nodal areas. Surgical resection was attempted 4 weeks later. Fifty-eight percent of the patients had squamous cell carcinoma whereas the remaining had other histologies like adenocarcinoma, large cell carcinoma, or a combination thereof. All the patients except two were followed up to a minimum of 5 years or until death. Sixty-four patients (82%) had T3 tumors whereas mediastinal nodal involvement was found in 41 patients (55%). Fifteen patients (20%) did not have the operation because of tumor progression, patient's refusal or death. All but two surgically treated patients had tumor resection. Of these 19% had histologically negative specimens, 9 patients (16%) had microscopic disease only, and 37 patients had gross residual disease at the time of surgery. The actuarial 5-year survival and recurrence-free survival rates for the entire group were 20% and 24%, respectively. Patients with a pathologic response had an actuarial recurrence-free survival rate of 53% at 5 years whereas only 17% of those with gross residual disease at surgery had remained recurrence-free at 5 years. One-half of the patients with clinically uninvolved nodes were living recurrence-free at 5 years whereas only 20% of the patients with N2 disease did so. The patterns of failure according to the histology and stage of the disease will be presented.