Radical radiation therapy of advanced lung cancer. Evaluation of prognostic factors and results of continuous and split course treatment

Abstract

One hundred patients with inoperable (80) or unresectable (20) bronchogenic carcinoma without evidence of spread beyond the thorax and supraclavicular nodes were planned for radical radiotherapy. Seventy-six patients received continuous irradiation (6000 rads in 30 treatments in 6 weeks, TDF 99) and 24 received split course therapy (2 courses of 2500 rads in 10 treatments with a 3 week break between courses, TDF 88). Forty-three patients had squamous cell carcinoma or adenocarcinoma and were considered to have favorable prognostic factors, while 57 patients had unfavorable prognostic factors: undifferentiated large cell or small cell carcinoma, supraclavicular metastases, SVC obstruction, superior sulcus tumors, or bone erosion in continuity with the tumor. Ninety-two patients completed the planned course of treatment. In patients completing treatment, local control of cancer within the irradiated volume was achieved in 58.5% of continuously irradiated patients and 45.4% of patients receiving split course therapy. Median survival was 1.2 months in patients not completing treatment and 12 months for the patients who completed treatment; 19% of the total group survived 3 years. Median and 3 year survivals of 14 months and 20.4% and of 9 months and 11% were observed for patients treated continuously and by the split course techniques, respectively. Corresponding survival figures for patients with favorable and unfavorable prognostic signs were 21 months and 26%, and 4 months and 11%, respectively. Implications of these data for treatment planning and patient selection for radical radiotherapy in bronchogenic carcinoma are discussed.