Surgical resection of metastases (mts) after biweekly chemotherapy with irinotecan, oxaliplatin and 5-fluorouracil/leucovorin (FOLFOXIRI) in initially unresectable metastatic colorectal cancer (MCRC)

Abstract

3553 Background: We conducted a phase I-II study with the triple drug combination FOLFOXIRI (irinotecan 125–175 mg/sqm day (d) 1, oxaliplatin 100 mg/sqm d1, l-LV 200 mg/sqm d1, 5-FU 3800 mg/sqm 48-h IV chronomodulated continuous infusion starting on d1, repeated every 2 weeks) and a subsequent phase II study with a simplified FOLFOXIRI regimen (irinotecan 165 mg/sqm d1, oxaliplatin 85 mg/sqm d1, l-LV 200 mg/sqm d1, 5-FU 3200 mg/sqm 48-h flat continuous infusion starting on d1, repeated every 2 weeks) respectively in 42 and 32 unselected MCRC pts with initially unresectable mts. Overall response rate, median progression free (PFS) and overall survival (OS) were 71% and 72%, 10.4 months (mos) and 10.8 mos, 26.5 mos and 28.4 mos respectively. Methods: In consideration of the high activity of these regimens 30 out of 74 pts (40%) could be revaluated for surgical resection of mts after chemotherapy. Among these 30 pts revaluated for surgery a R0 surgical resection could be performed in 19 pts (26% of the initial 74 pts). Characteristics of the 19 radically resected pts were: median age 66 years (45–73), ECOG PS ≥ 1 6 pts (32%), median CEA 10 ng/ml (1–288), median number of mts 3 (1–10), liver involvement ≥ 25% 12 pts (63%). Sites of disease were: liver only 14 pts, liver + lymphonodes 3 pts, liver + peritoneum 1 pt, liver + lung 1 pt. Mts were synchronous in 12 pts (63%) and metachronous in 7 pts with a median disease free interval of 12 mos. Results: After a median follow up of 28.8 mos median PFS is 18.6 mos and median OS is 39.6 mos. In 2 pts progressed after surgery a surgical re-resection and/or radiofrequency ablation was performed. Conclusions: First line FOLFOXIRI enables R0 surgical resection in about a quarter of pts with clearly initially unresectable MCRC. Median OS of resected pts is very promising. Prospective evaluation of FOLFOXIRI as neo-adjuvant treatment in initially unresectable colorectal cancer pts with liver and/or lung metastases is planned. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Aventis Pharma