Contradictory KRAS mutation test results in a patient with metastatic colon cancer: A clinical dilemma in the era of personalized medicine

Nicholas E. Lamparella, Bikramajit S. Saroya, Zhaohai Yang, Nabeel E. Sarwani, Wafik S. El-Deiry

Research output: Contribution to journalArticle

5 Scopus citations


The KRAS oncogene is mutated in 40-50% of colorectal cancers and confers resistance to EGFR-targeted therapy. In the clinic, agents such as cetuximab or panitumumab target the EGFR receptor for therapeutic benefit. Cetuximab was approved by the FDA in 2012 as first-line therapy for KRAS mutation-negative (wild-type), EGFR-expressing metastatic colorectal cancer, in combination with FOLFIRI (5-fluorouracil, irinotecan, leucovorin). Herein we report a case of metastatic colon cancer with conflicting testing results for the KRAS oncogene from two different reference laboratories. The discordant reports complicated the decision-making process regarding the administration of targeted anti-EGFR personalized therapy. As the second test result was wild-type from the same original pathological specimen, the patient was treated with cetuximab-containing combination chemotherapy and appeared to have a response after prior disease progression. It is unclear whether the observed response was fully due to regression of wild-type KRAS-containing tumor or any component of antibody-dependent cellular cytotoxicity to a heterogeneous tumor in this patient.

Original languageEnglish (US)
Pages (from-to)699-702
Number of pages4
JournalCancer Biology and Therapy
Issue number8
StatePublished - Aug 1 2013


All Science Journal Classification (ASJC) codes

  • Molecular Medicine
  • Oncology
  • Pharmacology
  • Cancer Research

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