Cancer Res Treat.  2017 Jan;49(1):37-43. 10.4143/crt.2016.069.

Use of a High-Throughput Genotyping Platform (OncoMap) for RAS Mutational Analysis to Predict Cetuximab Efficacy in Patients with Metastatic Colorectal Cancer

• Kim D
• Hong YS
• Kim JE
• Kim KP
• Lee JL
• Chun SM
• Kim J
• Jang SJ
• Kim TW

• KMID: 2367501
• DOI: http://doi.org/10.4143/crt.2016.069

Abstract

PURPOSE
Cetuximab demonstrates improved efficacy outcomes in patients with metastatic colorectal cancer (mCRC) harboring wild-type KRAS exon 2. Resistance to cetuximab is mediated by activating less frequent mutations in the RAS genes beyond KRAS exon 2. We performed extended RAS Mutational analysis using a high-throughput genotyping platform (OncoMap) and evaluated extended RAS analysis for predicting cetuximab efficacy in patients harboring wild-type KRAS exon 2 tumors following Sanger sequencing.
MATERIALS AND METHODS
Extended RAS analysis was performed on 227 wild-type KRAS exon 2 mCRC patients who received cetuximab as salvage treatment using OncoMap ver. 4.0. Targeted genes included exon 2, exon 3, and exon 4, both in KRAS and NRAS, and included BRAF exon 15. We assessed efficacy by the new RAS mutation status.
RESULTS
The OncoMap detected 57 additional mutations (25.1%): 25 (11%) in KRAS exon 2 and 32 (14.1%) beyond KRAS exon 2. Survival differences were observed after dividing patients into the wild-type RAS group (n=170) and mutant RAS group (n=57) using OncoMap. Progression-free survival was 4.8 months versus 1.8 months (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.32 to 0.61), and overall survival was 11.9 months versus 8.4 months (HR, 0.65; 95% CI, 0.47 to 0.88).
CONCLUSION
Sanger sequencing is not sufficient for selecting candidates for cetuximab treatment. High-throughput extended RAS genotyping is a feasible approach for this purpose and identifies patients who might benefit from cetuximab treatment.

Keyword

Colorectal neoplasms; Cetuximab; RAS genes; High-throughput nucleotide sequencing

MeSH Terms

Cetuximab*
Colorectal Neoplasms*
Disease-Free Survival
Exons
Genes, ras
High-Throughput Nucleotide Sequencing
Humans
Salvage Therapy
Cetuximab

Figure

• 

  Fig. 1. (A) Overall survival by RAS mutation status. (B) Progression-free survival by RAS mutation status. RAS WT, wildtype according to OncoMap; RAS MT, mutant according to OncoMap; all patients, WT KRAS exon 2 according to Sanger sequencing; +, censored time.

Reference

References

1. Jung KW, Won YJ, Kong HJ, Oh CM, Cho H, Lee DH, et al. Cancer statistics in Korea: incidence, mortality, survival, and prevalence in 2012. Cancer Res Treat. 2015; 47:127–41.

2. Di Fiore F, Blanchard F, Charbonnier F, Le Pessot F, Lamy A, Galais MP, et al. Clinical relevance of KRAS mutation detection in metastatic colorectal cancer treated by cetuximab plus chemotherapy. Br J Cancer. 2007; 96:1166–9.

3. Khambata-Ford S, Garrett CR, Meropol NJ, Basik M, Harbison CT, Wu S, et al. Expression of epiregulin and amphiregulin and K-RAS mutation status predict disease control in metastatic colorectal cancer patients treated with cetuximab. J Clin Oncol. 2007; 25:3230–7.

4. Ciardiello F, Tejpar S, Normanno N, Mercadante D, Teague T, Wohlschlegel B, et al. Uptake of KRAS mutation testing in patients with metastatic colorectal cancer in Europe, Latin America and Asia. Target Oncol. 2011; 6:133–45.

5. Heinemann V, von Weikersthal LF, Decker T, Kiani A, Vehling-Kaiser U, Al-Batran SE, et al. FOLFIRI plus cetuximab versus FOLFIRI plus bevacizumab as first-line treatment for patients with metastatic colorectal cancer (FIRE-3): a randomised, open-label, phase 3 trial. Lancet Oncol. 2014; 15:1065–75.

6. Douillard JY, Oliner KS, Siena S, Tabernero J, Burkes R, Barugel M, et al. Panitumumab-FOLFOX4 treatment and RAS mutations in colorectal cancer. N Engl J Med. 2013; 369:1023–34.

7. Schwartzberg LS, Rivera F, Karthaus M, Fasola G, Canon JL, Hecht JR, et al. PEAK: a randomized, multicenter phase II study of panitumumab plus modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) or bevacizumab plus mFOLFOX6 in patients with previously untreated, unresectable, wild-type KRAS exon 2 metastatic colorectal cancer. J Clin Oncol. 2014; 32:2240–7.

8. Peeters M, Oliner KS, Price TJ, Cervantes A, Sobrero AF, Ducreux M, et al. Analysis of KRAS/NRAS mutations in a phase III study of panitumumab with FOLFIRI compared with FOLFIRI alone as second-line treatment for metastatic colorectal cancer. Clin Cancer Res. 2015; 21:5469–79.

9. Van Cutsem E, Lenz HJ, Kohne CH, Heinemann V, Tejpar S, Melezinek I, et al. Fluorouracil, leucovorin, and irinotecan plus cetuximab treatment and RAS mutations in colorectal cancer. J Clin Oncol. 2015; 33:692–700.

10. Bokemeyer C, Kohne CH, Ciardiello F, Lenz HJ, Heinemann V, Klinkhardt U, et al. FOLFOX4 plus cetuximab treatment and RAS mutations in colorectal cancer. Eur J Cancer. 2015; 51:1243–52.

11. Tsiatis AC, Norris-Kirby A, Rich RG, Hafez MJ, Gocke CD, Eshleman JR, et al. Comparison of Sanger sequencing, pyrosequencing, and melting curve analysis for the detection of KRAS mutations: diagnostic and clinical implications. J Mol Diagn. 2010; 12:425–32.

12. MacConaill LE, Campbell CD, Kehoe SM, Bass AJ, Hatton C, Niu L, et al. Profiling critical cancer gene mutations in clinical tumor samples. PLoS One. 2009; 4:e7887.

13. Kim YM, Lee SW, Chun SM, Kim DY, Kim JH, Kim KR, et al. Analysis and comparison of somatic mutations in paired primary and recurrent epithelial ovarian cancer samples. PLoS One. 2014; 9:e99451.

14. Atreya CE, Corcoran RB, Kopetz S. Expanded RAS: refining the patient population. J Clin Oncol. 2015; 33:682–5.

15. Sohn BS, Kim TW, Lee JL, Ryu MH, Chang HM, Kang YK, et al. The role of KRAS mutations in predicting the efficacy of cetuximab-plus-irinotecan therapy in irinotecan-refractory Korean metastatic colorectal cancer patients. Oncology. 2009; 77:224–30.

16. Hecht JR, Douillard JY, Schwartzberg L, Grothey A, Kopetz S, Rong A, et al. Extended RAS analysis for anti-epidermal growth factor therapy in patients with metastatic colorectal cancer. Cancer Treat Rev. 2015; 41:653–9.

17. Bokemeyer C, Van Cutsem E, Rougier P, Ciardiello F, Heeger S, Schlichting M, et al. Addition of cetuximab to chemotherapy as first-line treatment for KRAS wild-type metastatic colorectal cancer: pooled analysis of the CRYSTAL and OPUS randomised clinical trials. Eur J Cancer. 2012; 48:1466–75.

18. Sommeijer DW, Karapetis CS, Zalcberg JR, Tu D, Jonker DJ, Simes J, et al. The relationship between rash, tumour KRAS mutation status and clinical and quality of life outcomes in patients with advanced colorectal cancer treated with cetuximab in the NCIC CTG/AGITG CO.17. Acta Oncol. 2014; 53:877–84.

19. Peeters M, Oliner KS, Parker A, Siena S, Van Cutsem E, Huang J, et al. Massively parallel tumor multigene sequencing to evaluate response to panitumumab in a randomized phase III study of metastatic colorectal cancer. Clin Cancer Res. 2013; 19:1902–12.