Analysis for phenotype of HNPCC in China.

aimThe aims of this study were to identify the clinicopathological features of Chinese HNPCC families and to evaluate the value of criteria for suspected HNPCC (sHNPCC) in clinical diagnosis.

methodsAccording to the follow-up records, 54 HNPCC families (including 12 ICG-HNPCC families and 42 sHNPCC families) were screened out from patients with colorectal cancers (CRCs), operated upon in 2(nd) Affiliated Hospital of Zhejiang University from 1984 to 2001. Clinical data of probands and tumor spectrum in these families were listed and analyzed.

results(1) Mean age, proportion of colonic cancer, poorly differentiated cancer, multiple CRCs and Dukes' A+B of the probands in ICG-HNPCC and sHNPCC kindred were 39ys and 47.5ys, 75 % and 62 %, 0 and 12.8 %, 16.7 % and 14.3 %, 58.3 % and 81 %,respectively. Compared with sporadic colorectal cancers, probands from ICG-HNPCC and sHNPCC families were obviously different at age of onset (P=0.025 and 0.031), tumor location (P=0.001 and 0.000), differentiation(P=0.002 and 0.011) and development of multiple tumors (P=0.014 and 0.002). (2) A total of 178 malignant neoplasms were found in 54 HNPCC families, including 139 colorectal cancers. Besides of colorectal cancer, extracolonic tumors occurred in stomach, endometrium, hepatobiliary system, and so on (8 gastric cancers, 6 endometrial cancers, 6 hepatobiliary system cancers and 19 others) can also be seen in Chinese ICG-HNPCC and sHNPCC families.

conclusion(1) Chinese HNPCC families have specific clinicopathological features, such as early onset, predilection for the involvement of colon, tendency of multiple CRCs, development of extracolonic tumors and well differentiation. (2) The criteria for suspected HNPCC is useful in clinical diagnosis and management of HNPCC.