Sub-total colectomy reduces the chance of a second primary colon cancer but has not been shown to have a survival advantage.rPeople who are not having regular colonoscopies are most likely to benefit.
Since MSH6 and PMS2 mutation carriers have a lower risk of CRC and the age at diagnosis is later than in patients with MLH1 and MSH2 mutations, start screening at 30 years in MSH6 and PMS2 carriers, unless an early-onset cancer exists in a given family.rr
A study of 114 Lynch Syndrome families comparing outcomes of screening at intervals of <2 years with >2 years demonstrated CRCs were diagnosed at a higher stage with the longer interval surveillance. Evidence supports screening 1-2 yearly.r
Since 57% of the neoplasms in Lynch Syndrome occur proximal to the splenic flexurer, visualisation to the caecum is essential.
Risk reducing medication
Considerable evidence supports the effectiveness of aspirin as risk-reducing medication for CRC in high-risk Lynch Syndrome patients (>50% reduction in CRC risk). While there is limited evidence about the optimal dose, a regular daily low-dose aspirin could be considered.r
Hysterectomy is the only proven intervention which significantly reduces the risk of endometrial cancer.r
There is no evidence to support a survival benefit from TVU and aspiration biopsy.r Where possible, surveillance should be offered in the context of a clinical trial.r
Risk reducing salpingo-oophorectomy (RRSO) reduces the risk of developing ovarian cancer in mutation carriers.r The risk of ovarian cancer is highest in MLH1 and MSH2 mutation carriers suggesting they would benefit more from surgery than MSH6 and PMS2 carriers. Disease free survival for ovarian cancers in patients with Lynch Syndrome appears higher than for BRCA associated ovarian cancer. Premenopausal women experience greater adverse effects from this surgery, which should be weighed against the small possible gain in life expectancy.r
Data extrapolated from other high risk groups demonstrates annual TVU and serum CA125 levels have low sensitivity and specificity for ovarian cancer, and do not reliably detect ovarian cancers at an early stage, nor do they affect outcomes. This is true of women in the general population and women at high risk of hereditary ovarian cancer.
Ovarian cancer risk management relies on risk-reducing removal of the ovaries and Fallopian tubes (RRSO).
See Cancer Australia for further information.
There is no evidence supporting the role of gastroscopy in the surveillance for gastric cancer in Lynch Syndrome patientsr, however, gastroscopy should be considered in families at high risk of gastric cancer.r
Urothelial transitional cell carcinoma
There is no evidence for the role of urine cytology in the surveillance of urothelial carcinomas in MMR gene carriers. One study of individuals with confirmed or suspected Lynch syndrome demonstrated urine cytology had a sensitivity for malignancy of only 29%.