Metastatic colorectal cancer treatment patterns according to kirsten rat sarcoma viral oncogene homolog genotype in U.S. Community-based oncology practices

Clin Colorectal Cancer. 2014 Sep;13(3):178-84. doi: 10.1016/j.clcc.2014.05.001. Epub 2014 Jun 23.

Abstract

Introduction: In 2008, the National Comprehensive Cancer Network guidelines were revised in light of the identification of the Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) gene as a biomarker of nonresponse to epidermal growth factor receptor inhibitors. This study sought to describe and compare real-world treatment patterns of metastatic colorectal cancer (mCRC) according to KRAS genotype in community-based oncology practices in the United States.

Materials and methods: Data from the ACORN (ACORN LLC, Memphis, TN) electronic medical record data warehouse, containing data of approximately 180,000 patients from 12 oncology practices across the United States were used. Records of adult patients with mCRC who had undergone KRAS testing between January 2008 and December 2011 were evaluated. Patient demographic characteristics, KRAS genotype, and treatment patterns were identified and compared.

Results: Six hundred forty-eight mCRC patients who were tested for KRAS were identified. Of these, 48.1% had wild type (WT), 42.3% mutant, and 9.6% unknown genotypes. Most patients (72.1%) were tested in 2009 or later, after the guideline revision. Bevacizumab-containing combinations were the most common first-line regimens in KRAS mutant and WT patients. Approximately 90% of patients received at least 1 line of therapy, however, WT patients received significantly more lines of therapy than KRAS mutant patients (2.6 ± 1.5 vs. 2.1 ± 1.2; P < .001).

Conclusions: KRAS WT and mutant genotypes had similar first-line regimens; however, WT patients received more lines of therapy. Although there does not appear to be a lag between changes in guidelines and treatment practice, professional and government organizations must keep up with the changing science and disseminate this information to oncologists in a timely manner.

Keywords: Electronic medical records; Guidelines; KRAS testing; NCCN; Real-world treatment patterns.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antibodies, Monoclonal / administration & dosage
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antineoplastic Combined Chemotherapy Protocols / administration & dosage
  • Bevacizumab
  • Biomarkers, Tumor / genetics*
  • Camptothecin / administration & dosage
  • Camptothecin / analogs & derivatives
  • Capecitabine
  • Cetuximab
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / pathology*
  • Community Health Services*
  • Deoxycytidine / administration & dosage
  • Deoxycytidine / analogs & derivatives
  • ErbB Receptors / antagonists & inhibitors
  • Female
  • Fluorouracil / administration & dosage
  • Fluorouracil / analogs & derivatives
  • Genotype*
  • Humans
  • Leucovorin / administration & dosage
  • Male
  • Middle Aged
  • Neoplasm Metastasis
  • Organoplatinum Compounds / administration & dosage
  • Oxaliplatin
  • Panitumumab
  • Practice Guidelines as Topic
  • Practice Patterns, Physicians'*
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins p21(ras)
  • United States
  • Young Adult
  • ras Proteins / genetics*

Substances

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Biomarkers, Tumor
  • KRAS protein, human
  • Organoplatinum Compounds
  • Proto-Oncogene Proteins
  • Oxaliplatin
  • Deoxycytidine
  • Bevacizumab
  • Capecitabine
  • Panitumumab
  • ErbB Receptors
  • Proto-Oncogene Proteins p21(ras)
  • ras Proteins
  • Cetuximab
  • Leucovorin
  • Fluorouracil
  • Camptothecin

Supplementary concepts

  • Folfox protocol
  • IFL protocol