Detection of DNA Mismatch Repair Deficiencies in Endometrial Carcinomas

Strategic Insights -

Research from the University of British Columbia has shed light on the genetic characteristics of endometrial carcinomas, a type of cancer that affects the lining of the uterus. The study found that a proportion of these cancer cases are associated with deficient DNA mismatch repair (MMR), which can be identified through immunohistochemistry (IHC) testing. This discovery has significant implications for the identification of Lynch syndrome and the stratification of cases for future clinical trials. According to the researchers, the implementation of MMR IHC in endometrial cancer classification schemes can enable more effective diagnosis and treatment of this disease.

Key Takeaways:

  • A significant proportion of endometrial carcinomas (ECs) are associated with deficient DNA mismatch repair (MMR), which is characterized by high levels of microsatellite instability (MSI).
  • Immunohistochemistry (IHC) testing can be used to detect MMR deficiencies in ECs, with a concordance of 93.3% between IHC and MMR IHC in a cohort of 89 patients.
  • The implementation of MMR IHC in future EC classification schemes can enable stratification of cases for future clinical trials and assist identification of Lynch syndrome.
  • Detection of MSI in ECs is essential for identifying women who should be tested for Lynch syndrome and for identifying a phenotype with specific prognostic and predictive implications.
  • The study recommends comparing the two most common methodologies for MSI assessment, Pentaplex mono and di-nucleotide PCR, with MMR IHC in future EC classification schemes.
  • The research has significant implications for the diagnosis and treatment of endometrial cancer, particularly in the identification of Lynch syndrome and the stratification of cases for future clinical trials.

Statistics:

  • 93.3% concordance between IHC and MMR IHC in a cohort of 89 patients with EC (95% CI: 85.9%-97.5%)
  • 89 cases were included in the comparison of MSI and MMR status
  • The accuracy of MMR IHC in detecting MSI in ECs was significant (p<0.001)

Sources:

  • Detection of DNA mismatch repair (MMR) deficiencies by immunohistochemistry can effectively diagnose the microsatellite instability (MSI) phenotype in endometrial carcinomas. Gynecologic Oncology, 2015;137(2):306-310.
  • Elsevier. (www.elsevier.com)
  • Academic Press Inc. (www.elsevier.com)