Abstracts
1998 Digestive Disease Week

#999

RESULTS OF A 3-YEAR SURVEILLANCE PROGRAM OF MEMBERS OF FAMILIES WITH HEREDITARY NON-POLYPOSIS COLORECTAL CANCER. GB Rossi, M de Bellis, P Marone, PF Maione, L. Panariello*, F Petrulio, A Tempesta and P.Izzo* Endoscopy Unit, National Cancer Institute of Naples; *Department of Molecular Biology, School of Medicine, I University of Naples, Italy.

Introduction: The adenoma-carcinoma sequence is accelerated in HNPCC. Therefore, a surveillance program is mandatory in HNPCC family members. In the present study we analyzed the clinical findings at the time of the 1st follow-up colonoscopy in a subset of HNPCC family members who are undergoing a surveillance program at our Institution. Patients and methods : 48 members of 12 HNPCC families, identified on the basis of the Amsterdam criteria, have been followed for 3 years. In two of these families a mutation of the hMLH1 gene was identified. There were 23 males and 25 females, with a mean age of 46 years (range 18-72). The prescribed 1-year screening interval was not fulfilled by all patients and several of them underwent 1st follow-up colonoscopy up to 37 months after the first one. Results : At the time of the 1st follow-up colonoscopy 22 adenomas [5 with high grade dysplasia (HGD] were detected in 17 subjects and 3 colorectal cancers (CRC) were diagnosed. The ratio adenoma/carcinoma was 0.14. The correlation between the clinical findings (adenomas with both HGD and LGD and CRC) and the interval of time between two following colonoscopies showed a strong dispersion of the data. However, 3 out of 5 adenomas with HGD were detected in subjects who had undergone colonscopy 36 months after the first one. Furthermore, the 3 patients with CRC underwent follow-up colonoscopy respectively 24, 33 and 36 months after the first negative examination. In our series there were more left sided adenomas (#14) than right sided adenomas (#8), and this data showed no difference respect to that of a series of 80 patients with sporadic adenomas. In the HNPCC group 5 out of 22 adenomas showed HGD, while in the sporadic adenomas group 11 polyps had HGD. There is not a significant difference between the two groups, even if HGD seems to be more frequent in HNPCC adenomas. In our series the distribution of lesions seems to follow a familial trend. In 6 HNPCC families we found a prevalent location of lesions in the right colon in 3 families, and in the left colon in the other 3 families. Finally, during the surveillance period we diagnosed only 1 extracolonic tumor (early gastric cancer). Conclusions: Our data showed a prevalent location of the lesions in the left colon. It suggests a familial trend for the prevalent location of the lesions and a 1-year screening interval for the surveillance of HNPCC family members.

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