Lynch syndrome for the gynaecologist 2020 Flashcards
Inheritance
AD
Cancers associated
o Breast 13%
o Endometrial 57%
o Ovary 17%
o Colon 45% rectum 13%
Cause of Lynch
- Mutations in DNA Mismatch repair system (MMR) e.g. MLH1,MSH2,MSH6,PMS2
Incidence
- Incidence 1-278-440.
Most common inherited cancer predisposition syndrome
95% unaware of Dx.
What proration of endometrial cancer due to Lynnch
3%
What proportion of non-serous epithelial caners are MMR deficient
21%
Which variant has highest risk of endometrial cancer at 70 year
MSH 2
Which variant has highest risk of ovarian cancer at 70 years
MSH 2
Which cancer Lynch carriers most likely to die from. Highest risk mutation
Colorectal cancer
MLH1
How is colon cancer screened for
2 x years colonoscopy
What risk reducing strategy for gynaecological conditions
o Be aware reg flag symptoms
o Can offer TAH + BSO after completed family – timing of surgery gene specific
MLH1/MSH2 – 35yrs
MSH6 – 40yrs
PMHS – 50yrs
Normal risks – early menopause, CVD risk
o Aspirin from 18yrs
o Lifestyle advice – smoking cessation/weight loss/exercise
o Hormone based therapy – reproductive age, reduced endometrial proliferation
Survival rates at 10 years for endometrial cancer from Lynch?
90%
Prevalance of Lynch in endometrial and ovarian cancer
Endoemtiral 3%
Ovarian 1-25
Does tumour based testing identify women with Lynch -
no stratifies risk of condition, need gremlin testing
Does Lynch directly effect fertility
- No effect on fertility, but 50% passing onto children, offer PGT
