We investigated the efficacy of docetaxel (D) in combination with carboplatin (C) in the treatment of non-small cell lung cancer (NSCLC) patients. Since 1996, 123 with inoperable NSCLC were enrolled in the study; 120 (108 males, 12 females; mean age 58.0+/-8.3 years) were evaluated. Of those, 46 patients had squamous carcinoma, 44 adenocarcinoma, 11 large cell carcinoma and 19 undifferentiated tumours. Eligibility criteria included, documented inoperable NSCLC, WHO performance status (PS) 0-1, age up to 70 years, and normal renal and hepatic function. A total of 622 cycles of chemotherapy (CHT) (median 7 (95% CI 6.2-7.47), courses per patient) were administered. Each cycle consisted of 100 mg/m(2) of docetaxel in a 2-h infusion with C at a dose of area under the curve (AUC) of 6 on day 1. This regimen was repeated every 28 days up to eight cycles. Of the patients, five (4%) achieved complete response, 49 (40%) partial response, 47 (39%) had stable disease and 19 (15%) had progressive disease. The median survival was 12 months for all patients, 12 for the four patients with stage IIb disease, 18 for the patients with stage IIIa disease, 20 for the 29 patients with stage IIIb disease, and 11 for the 65 stage IV patients. The median time to progression was 8 months (90 patients). Toxicity was, grade 3/4 neutropenia, 18 patients (15%); grade 3/4 anaemia, 6 patients (5%); and tolerable peripheral neuropathy, 16 patients (13.3%). Responders received radiotherapy (total dose, 50 Gy in 4 weeks) between the 6th and 8th cycle. Among responders with initial stage IIIb disease, 7 (5%) underwent surgical resection. Patients with early progression of the disease received the same dose of radiotherapy between 2nd and 3rd cycle. The study is ongoing, and six patients (5%) are still alive (after 3 years). Preliminary results indicate that the D/C combination is very active in the treatment of NSCLC with tolerable toxicity. It appears that this drug combination is also good as neoadjuvant therapy in inoperable NSCLC patients.