Correlation of progression-free and post-progression survival with overall survival in phase III trials of first-line chemotherapy for advanced epithelial ovarian cancer

PURPOSE OF INVESTIGATION: The authors examined the relation between post-progression survival (PPS) and overall survival (OS) in phase III trials of first-line chemotherapy for advanced epithelial ovarian cancer. MATERIALS AND METHODS: The authors partitioned OS into progression-free survival (PFS) and PPS and evaluated the relation between OS and either PFS or PPS. They also examined whether any association might be affected by the year of completion of trial enrollment. RESULTS: The average PPS was longer in recent trials than in older trials (26.9 vs. 20.2 months,p = 0.0002). For all trials, PPS was strongly associated with OS (r = 0.94), whereas PFS was more moderately but still strongly correlated with OS (r = 0.83). The average proportion of median OS accounted for by median PPS significantly increased from 54.1% in older trials to 60.3% in recent trials (p = 0.0001). CONCLUSION: The present findings indicate that, especially for recent trials, PPS is more highly associated than PFS with OS in first-line chemotherapy for advanced epithelial ovarian cancer.