Do the time to chemotherapy response and the dose intensity have an impact on patient outcome in advanced non-small cell lung cancer?

PURPOSE: To better define the importance of early response rate (RR) as well as dose intensity (DI) in advanced non small cell lung cancer (NSCLC) patients treated with platinum-based combination chemotherapy. PATIENTS AND METHODS: Analysed were stage IIIB and IV NSCLC patients included in 4 prospective clinical trials. All of them were treated with cisplatin 120 mg/m2 (the majority of patients) or carboplatin 500 mg/m2, and since 2000 with AUC 5 (the minority of patients) with second-generation platinum-based regimens. Responding patients (complete response/CR and partial response/PR) were divided into 4 different categories, depending on the time when response was first registered. DI and total dose (TD) of cisplatin was calculated for 93 patients with response or stable disease (SD).
RESULTS: Among 362 patients analysed, 117 (32%) were responders. Although "early" responders (54 patients after the 2nd cycle, median survival 10 months; 42 patients after the 3rd cycle, median survival 11 months) lived shorter than "late" responders (11 patients after the 4th cycle median survival 12 months; 10 patients after the 5th cycle, median survival 19 months), these differences were not statistically significant, neither in terms of overall survival (OS) nor in time to progression (TTP). DI in patients with CR+PR+SD was 30 mg/m2/week (median). TD of cisplatin in CR+PR patients was 577 mg, whereas it was 475 mg in patients with SD (p=0.004). These differences followed significant differences in the number of the cycles received and median survival between CR+PR vs. SD patients.
CONCLUSION: Early response was not associated with better survival, DI in SD patients did not differ from responding patients, but responding patients received more cisplatin and lived longer.