ANDREW LATCHFORD BSc, MBBS, MD, FRCP CONSULTANT GASTROENTEROLOGIST

BACKGROUND COLORECTAL CANCER  Interaction between genotype and the environment  The UK lifetime risk of CRC is ≈5%  Many people by chance alone have at least one affected relative  number of affected relatives, risk of developing CRC

GENETIC RISK  Spectrum of risk  High-risk, overwhelming contribution of genotype –≤5% CRC, at risk of ‘inherited bowel cancer’  Low- and moderate-risk, genotype contributes to risk, role in ≈30%

ASSESSMENT OF RISK  Accurate family history –site and age at diagnosis of ALL cancers in family members, –presence of colorectal adenomas/other polyps  The family history has limitations –small families –incorrect information, early death of individuals before they develop cancers.

ASSESSMENT OF RISK  A full personal history –symptoms –previous large bowel polyps –previous large bowel cancers –cancers at other sites –other risk factors for colorectal cancer (IBD, acromegaly)

LOW RISK GROUP  Individuals in this group have: –no personal history of bowel cancer; no confirmed family history of bowel cancer; or –no first-degree relative (i.e. parent, sibling or child) with bowel cancer; or –one first-degree relative with bowel cancer diagnosed at age 50 years or older  No evidence to support invasive surveillance

MODERATE RISK GROUP  Low-moderate risk –those with one affected relative diagnosed under 50 years; or –two affected first-degree relatives diagnosed at at age 60 years or older  ONE OFF COLONOSCOPY AGE 55 YEARS

MODERATE RISK GROUP  High-moderate risk –three or more affected relatives in a first degree kinship (none under 50 years) –two affected relatives diagnosed under 60 years (or with a mean age at diagnosis under 60 years) in a first degree kinship  5 YEARLY COLONOSCOPY FROM AGE 50 YEARS

HIGH RISK GROUP  Criteria include –member of family with polyposis syndrome –member of family with Lynch syndrome –pedigree suggestive of autosomal dominantly inherited colorectal (or other Lynch syndrome- associated) cancer –pedigree indicative of autosomal recessive inheritance, MYH associated polyposis (MAP)  Condition specific management

PEARLS AND PITFALLS  Family history assessment of risk but difficult to do well  If between risk groups, manage the family as if in the higher risk group  Family histories evolve, risk group change if cancers develop/excluded  ASPIRIN THE FUTURE?

ANY QUESTIONS?