Superior sulcus (Pancoast) tumors (SST) are uncommon carcinomas of the lung with distinctive failure patterns and a somewhat more favorable prognosis than other sites of lung cancer. The most effective use of surgery (S), radiation (R), and chemotherapy (C) is not resolved. Most reported series include patients treated before the era of computed tomography (CT). A retrospective study was undertaken of all previously untreated patients with SST who received definitive management at the University of Texas M.D. Anderson Cancer Center between January 1977 and December 1987. Eighty-five patients were treated: the male:female ratio was 2.7:1, and the ages ranged from 35 to 80 (median 59) years. Karnofsky performance status (KPS) was 80 or more in 70 patients (82%). Thirty patients (35%) had lost 5% or more body weight. All had histologic or cytologic confirmation of carcinoma: 25% were squamous cell, 2% small cell, 54% adenocarcinoma, and 6% were large cell carcinoma (12% were not classified). After complete evaluation, 43 were classified as clinical Stage IIIA and 42 were Stage IIIB. One Stage IIIA patient received surgery, 13 surgery + radiation therapy, 2 surgery + radiation therapy and chemotherapy, 19 radiation therapy and 8 radiation therapy + chemotherapy. Seven Stage IIIB patients received surgery + radiation therapy, 12 radiation therapy, 2 surgery + radiation therapy + chemotherapy, 17 radiation therapy + chemotherapy and 4 chemotherapy. Surgery was a component of therapy more frequently in Stage IIIA than IIIB (p less than .05) and systemic treatment chemotherapy was used significantly more often (p less than .01) in Stage IIIB. Twenty-six patients (31%) lived 2 years or more (25+ to 131+ months) after treatment. Stage IIIA patients had a 46.5% 2-year survival rate compared to 20.6% for Stage IIIB (p = .0042). The one patient treated with surgery alone lived 2 years; 23% (7/31) of patients who had radiation therapy alone and none of the 4 who had chemotherapy lived 2 years. When surgery was a component of treatment, 52% (13/25) lived 2+ years, compared with 22% (13/60) when surgery was not part of treatment. When radiation therapy was part of treatment 31% lived 2 years and when chemotherapy was used, 18% lived 2 years. Fifty-two patients (61%) had control of the local tumor: their survival was significantly greater (p less than .01) than those who had local failure.(ABSTRACT TRUNCATED AT 400 WORDS)