[Clinical value of screening hereditary nonpolyposis colorectal cancer in China with protocol recommended by NCCN guidelines].
OBJECTIVE
To investigate the effect of the protocol recommended by NCCN-2007 on the diagnosis of hereditary nonpolyposis colorectal cancer (HNPCC) in China.


METHODS
NCCN protocol consists of identifying HNPCC characteristics according to the revised Bethesda Guidelines,genetic counseling with immunohistochemistry and finally genetic testing. Four hundred and nineteen patients diagnosed as colorectal cancer from January 2002 to February 2006 were selected. The hMLH1 and hMSH2 immunostaining were implemented for 90 patients who fulfilled the revised Bethesda Guidelines, in whom 8 patients fulfilling the Amsterdam II (Criteria were classified as group A and the other 82 patients as group B. The frozen tissues were collected from patients who showed loss of hMLH1 or hMSH2 protein expression, then RNA was extracted, and RT-PCR and cDNA sequencing were adopted to detect the germline mutations of hMLH1 and hMSH2.


RESULTS
Tumor tissues from 18 patients showed loss of hMLH1 or hMSH2 protein expression (5 patients in group A and 13 in group B). Finally, 21 patients(8 in group A and 13 in group B showed loss expression of MMR protein) were diagnosed as HNPCC, including 2 cases of hMLH1 and 1 case of hMSH2 mutations. These 3 cases with cDNA mutations did not fulfill the Amsterdam II( Criteria, and were finally diagnosed as HNPCC.


CONCLUSIONS
The protocol recommended by NCCN-2007 offers a useful approach to identify HNPCC patients,and reduces the possibility of missed diagnosis of HNPCC.
Shen
Kai
K
Department of Gastrointestinal Surgery, Peking University Peopleos Hospital, Beijing, China.
Wang
Shan
S
Ye
Ying-Jiang
YJ
Yin
Mu-Jun
MJ
Yang
Xiao-Dong
XD
Xu
Feng
F
Liang
Bin
B
Jiang
Ke-Wei
KW
Cui
Zhi-Rong
ZR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020137:Base Pair Mismatch; D002681:China; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D005820:Genetic Testing / Q000379:methods*; D017408:Guidelines as Topic; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult