A new cisplatin/gemcitabine schedule in locally advanced (IIIB) and metastatic (IV) non-small cell lung cancer: relationship between dose-intensity and efficacy. A phase II study.

Background: Cisplatin/gemcitabine are one of the "standard" chemotherapy schedules in locally advanced and metastatic NSCLC cancer. A number of trials documented that omission of gemcitabine on day 15 and reduction of cisplatin up to 70 mg/mq are equivalent in term of response rates to "classic" administrations on days 1, 8 and 15 with cisplatin 100 mg/mq. The aim of this study was to confirm this evidence and to demonstrate that a further reduction of gemcitabine dose-intensity may be performed with the same efficacy on response.
Patients and Methods: Fifty untreated patients with locally advanced and metastatic NSCLC entered the study: 24 stage IIIB and 26 stage IV. The median age was 65 years (range 32-76); 44 males and 6 females Genicitabine was administered 1000 mg/mq weekly on days 1 and 8 followed by a 2-week rest and cisplatin 80 mg/mq on day 2 of each 28-day-cycle.
Results: Forty-five patients were evaluable for response and all for toxicity. The overall response rates were 35.5% with 16 partial responses (95% Confidence Interval: 32%-61%). Most of the objective responses were seen in IIIB patients (56% of the stage IIIB and 44% of the stage IV patients responded). According to the intent-to-treat-principle, the response rates were 32% (16 out of 50 patients). The median dose-intensity of gemcitabine and cisplatin was respectively 477.6 mg/mq/week (481.4 for responders) and 19.5 mg/mq/week (19.9 mg/mq for responders). The median response duration was 5 months (range 1-18) and the median time to progression was 5 months (1-21); median survival was 9 months (range 2-31). The main toxicity was haematological: thrombocytopenia grade IV in 5 patients (10%) and grade III in 11 patients (22%); neutropenia grade III-IV in 4 patients (8%); grade III anemia in 3 (6%). Asthenia was the most significant non-haematological toxicity and was observed in 19 patients (38%).
Conclusion: This trial confirmed the efficacy of a schedule with 2 administrations of gemcitabine (on days 1, 8) and a cisplatin dose on day 2 lower than 100 mg/mq. Moreover, the same efficacy was obtained with a median-dose intensity of cisplatin and gemcitabine lower than planned in a 21-day-schedule. For safety and low toxicity, we think that this schedule provides another chance to treat patients with non-small cell lung cancer, especially the elderly or patients with coexistent medical illnesses.