Figure 1

Clinical and molecular strategies developed for the selection and identification of HNPCC. As far as the experience in Modena is concerned (where a specialised colorectal cancer Registry was instituted in 1984), the number corresponding to each category, for the period 1984–1998, are the following. Registered patients: 2462. Sporadic+familial cases: 2207. HNPCC+suspected HNPCC+early-onset cases: 255. MSI+: 53. Lack of protein expression: 21 (immunohistochemistry). Families which underwent genetic testing: 15. Families with constitutional mutations: 12.