Mutation Profiling and Microsatellite Instability in Stage II and III Colon Cancer: An Assessment of Their Prognostic and Oxaliplatin Predictive Value

作者：Gavin Patrick G; Colangelo Linda H; Fumagalli Debora; Tanaka Noriko; Remillard Matthew Y; Yothers Greg; Kim Chungyeul; Taniyama Yusuke; Kim Seung Il; Choi Hyun Joo; Blackmon Nicole L; Lipchik Corey; Petrelli Nicholas J; O'Connell Michael J; Wolmark Norman; Paik Soonmyung; Pogue Geile Kay L^*

来源：Clinical Cancer Research, 2012, 18(23): 6531-6541.

DOI：10.1158/1078-0432.CCR-12-0605

Purpose: The purpose of this study was to examine the prognostic and oxaliplatin predictive value of mismatch repair (MMR) status and common hot spot mutations, which we previously identified in stage II and III colon cancer.
Experimental Design: Mutations in BRAF, KRAS, NRAS, MET, and PIK3CA were profiled in 2,299 stage II and III colon tumors from National Surgical Adjuvant Breast and Bowel Project (NSABP) clinical trials C-07 (n = 1,836) and C-08 (n = 463) with Type Plex chemistry and mass spectrometry. C-07 tested the worth of adding oxaliplatin to 5-fluorouracil plus leucovorin, and C-08 tested the worth of adding bevacizumab to FOLFOX. Cox proportional hazard models were used to assess prognostic or oxaliplatin predictive value of mutations for tumor recurrence, overall survival (OS), and survival after recurrence (SAR).
Results: BRAF mutations were associated with MMR-deficient tumors (P < 0.0001), poor OS [HR, 1.46; 95% confidence interval (CI), 1.20-1.79; P <= 0.0002], and poor SAR (HR, 2.31; 95% CI, 1.83-2.95; P < 0.0001). Mutations in KRAS, NRAS, MET, and PIK3CA were not associated with recurrence, OS, or SAR. MMR-deficient tumors were associated with an improved prognosis based on recurrence (HR, 0.48; 95% CI, 0.33-0.70; P < 0.0001). Mutations and MMR status were not predictive for oxaliplatin benefit.
Conclusions: This study shows that BRAF mutations profiled from stage II and III colon cancer tumors were associated with poor SAR and validates and explains, at least in part, previous observations associating it with poor OS. Profiling of all of these mutations is warranted for future clinical trials testing new targeted therapies that block relevant signaling pathways. Such clinical trials are under development at NSABP. Clin Cancer Res; 18(23); 6531-41.

• 出版日期2012-12-1