endometrial cancer and Lynch syndrome

Last edited 10/2020 and last reviewed 05/2021

Lynch syndrome is an inherited condition that increases the risk of certain types of cancer, including endometrial and colorectal cancer

• Lynch Syndrome is a highly penetrant, autosomal dominant cancer predisposition syndrome caused by monoallelic germline mutation in a mismatch repair gene, specifically MLH1, MSH2, MSH6 or PMS2, or by germline deletion within EPCAM that leads to epigenetic silencing of the adjacent MSH2 gene(1)
• mutation carriers are at increased risk of developing colorectal cancer and endometrial cancers, the two major component tumors of Lynch Syndrome, as well as cancers of the ovary, stomach, kidney, urinary tract, biliary tract, small intestine and skin (1)
• approximately 2–6% of endometrial cancers are attributed to Lynch Syndrome (2)


• risk of other cancers if Lynch syndrome-associated endometrial cancer (3)
  • following endometrial cancer, women carrying MMR gene mutations had the following 20-year risks of other cancer cancers:
  • colorectal cancer (48%, 95% confidence interval [CI] = 35% to 62%);
  • cancer of the kidney, renal pelvis, or ureter (11%, 95% CI = 3% to 20%);
  • urinary bladder cancer (9%, 95% CI = 2% to 17%);
  • and breast cancer (11%, 95% CI = 4% to 19%).
  • compared with the general population, these women were at statistically significantly elevated risks of colorectal cancer (standardized incidence ratio (SIR) = 39.9, 95% CI = 27.2 to 58.3), cancer of the kidney, renal pelvis, or ureter (SIR = 28.3, 95% CI = 11.9 to 48.6), urinary bladder cancer (SIR = 24.3, 95% CI = 8.56 to 42.9), and breast cancer (SIR = 2.51, 95% CI = 1.17 to 4.14)
  • this study revealed that, over a 20-year period, Lynch syndrome-associated endometrial cancer there was increased subsequent risk of colorectal cancer, urinary tract cancers, bladder cancer, and breast cancer
• risk of endometrial cancer if Lynch syndrome-associated colorectal cancer (4)
• evidence suggests that approximately one quarter of women diagnosed with Lynch syndrome-associated colorectal cancer developed endometrial cancer within 10 years

Reference:

• Lynch HT, Snyder CL, Shaw TG, Heinen CD & Hitchins MP Milestones of Lynch syndrome: 1895–2015. Nat. Rev. Cancer 15, 181–194.
• Wong A & Ngeow J Hereditary syndromes manifesting as endometrial carcinoma: how can pathological features aid risk assessment? Biomed. Res. Int 2015, 219012.
• Win AK et al. Risks of Colorectal and Other Cancers After Endometrial Cancer for Women With Lynch Syndrome.J Natl Cancer Inst. 2013 Feb 20; 105(4): 274–279
• Obermair A et al.Risk of endometrial cancer forwomen diagnosed with HNPCC-related colorectal carcinoma. Int J Cancer. 2010 Dec 1; 127(11): 2678–2684.