Hereditary nonpolyposis colorectal cancer: results of long-term surveillance in 50 families. - Vasen,H.F.; Taal,B.G.; Nagengast,F.M.; Griffioen,G.; Menko,F.H.; Kleibeuker,J.H.; Offerhaus,G.J.; Meera Khan,P. (Eur J Cancer, 1995)