Comparison of progression-free survival (PFS) and tumor response as endpoints for predicting overall survival (OS) in untreated extensive-stage small cell lung cancer (ED-SCLC): Findings based on North Central Cancer Treatment Group (NCCTG) trials
8085 Background: Historically, tumor response has been the primary endpoint in phase II (P2) trials in ED-SCLC. We investigated the suitability of alternate PFS based endpoints to predict OS as early evidence of efficacy in the P2 setting. Methods: Individual patient (pt) data from 942 pts from 11 previously untreated ED-SCLC P2 and phase III (P3) platinum- or paclitaxel-based treatment trials were pooled. Best response (BR), response confirmed (RC), objective status at 16 weeks (RR16), and PFS rate at 5 and 6 months were considered. Percent agreement (PA) and kappa (k) for PFS5, PFS6, BR, RC, and RR16 with OS at 12 months (OS12) was calculated on a per-pt basis and predictive utility was assessed using the area under the receiver operating characteristic (A- ROC) curve in logistic models. Cox models were used to assess the prognostic impact of the endpoints on subsequent survival, using landmark analysis. Results: The median OS and PFS were 9.6 m and 5.5 m, respectively. PFS5 and PFS6 had the highest PA, k, and A-ROC values, and were predictive of subsequent survival in the landmark analysis (p <0.0001; c-statistics ≥ 0.60). While RR16 and BR were significantly associated with subsequent survival (p<0.0001, c-statistics of 0.61 and 0.57, respectively) the PA, k, and A-ROC values were lower. Conclusions: PFS rate at 5 and 6 months is more predictive of 12-month OS and subsequent survival than tumor response in untreated ED-SCLC. PFS based endpoints should be routinely used as primary endpoints in P2 trials within ED-SCLC. [Table: see text] No significant financial relationships to disclose.
The value of combined modality therapy in elderly patients with stage III non-small cell lung cancer (NSCLC)
19503 Background: This study was performed to assess the value of combined modality therapy in elderly patients by comparing the differences in outcome of those who received radiotherapy (RT) alone or RT plus chemotherapy for stage III NSCLC. Methods: North Central Cancer Treatment Group (NCCTG) performed 2 recent phase III trials for stage III NSCLC. The first trial, 90–24–51, included 3 arms: once-daily radiotherapy (QDRT) alone, twice daily RT (BIDRT) alone, and concurrent chemotherapy plus BIDRT. The second trial, 94–24- 52 included 2 arms and compared concurrent chemotherapy with either QDRT or BIDRT. The chemotherapy arms of both trials included etoposide and cisplatin administered concurrently with RT. Only the patients ≥65 years of age (elderly) who participated in these trials were included in this analysis. Results: Of the 166 elderly patients included in this analysis, 37 received RT alone and 129 received concurrent chemotherapy plus RT. The median and 5-year survival rates were 10.5 months and 5.4% for the RT alone group compared to 13.7 months and 14.7% for the RT plus chemotherapy group (log-rank p=0.05). Patients who received RT plus chemotherapy experienced significantly greater severe (grade ≥3) toxicity than those who received RT alone (89.9% versus 32.4%, p < 0.01). Conclusions: Elderly patients who participated in these trials appear to gain a survival advantage from RT and chemotherapy compared to RT alone. As is the case with younger patients, this benefit comes at the cost of additional toxicity. No significant financial relationships to disclose.
Updated analysis of SWOG 0023: A randomized phase III trial of gefitinib versus placebo maintenance after definitive chemoradiation followed by docetaxel in patients with locally advanced stage III non-small cell lung cancer
7513 Background: Early clinical studies with gefitinib (G) showed promising efficacy and mild toxicity in patients (pts) with advanced NSCLC. Thus, G was an ideal agent to evaluate in a maintenance setting in stage III disease following definitive treatment. Methods: Untreated pts with stage III NSCLC, a PS of 0–1 and adequate organ function were eligible. Patients received the SWOG 9504 core regimen (cisplatin 50 mg/m2, d1 & 8 plus etoposide 50 mg/m2 day 1–5, every 28 days for 2 cycles with concurrent thoracic radiation, 1.8–2 Gy fractions/day, total dose 61 Gy, followed by 3 cycles of docetaxel 75 mg/m2). Non- progressing pts were randomized to G 250 mg per day or placebo (P) until disease progression, intolerable toxicity or 5 years. The planned sample size was 672, to confer power of 0.89 to detect a 33% increase over the expected median survival of 21 months (one-sided 0.025 level logrank test). Randomization was stratified by stage and histology. Results: Enrollment began in July 2001. An unplanned interim analysis prompted by outside data was conducted in April 2005 and the alternative hypothesis of improved survival was rejected at the 0.0015 level for 243 randomized patients. The study closed and preliminary results were reported (ASCO 2005). Now with a median follow up of 27 months, median survival for the G arm (n=118) was 23 months and was 35 months for the P arm (n=125) (two sided p=0.013). Overall survival for the 571eligible patients was 19 months. ≥ Grade 3 toxicities in the G arm were rash (7%), diarrhea (7%) and pneumonitis (3%). Conclusion: In this unselected population G did not improve survival. Decreased survival was due to cancer not G toxicity. Three year survival estimates will be presented. Molecular studies of the EGFR pathway are underway and will be correlated with outcomes. No significant financial relationships to disclose.