A protocol was made for an interventional randomized controlled trial for prevention of colorectal cancer. The subjects were 300 patients with familial adenomatous polyposis from collaborative multiple institutions. Four regimens were formulated for prevention of colorectal cancer. Regimen A was dietary guidance, wheat bran biscuits and decaffeinated green tea extract tables, regimen B was dietary guidance, wheat bran biscuits and non-function tablets, regimen C was dietary guidance and decaffeinated green tea extract tables, regimen D was dietary guidance and non-function tablets. The main end point of the trial is number and size of colorectal adenoma after 2 years. Recruiting of subjects was started in September, 2000. The trial will be completed in March, 2004.
The purpose of this study was to investigate what physicians did for patients with genetic disorders and their families, and to clarify physicians'need and level of knowledge regarding genetic counseling.
Self-administered questionnaires were mailed to 57 medical doctors who worked at a university hospital, from which there were 30 respondents.
Sixteen of the 30 respondent physicians had experience of practice with and/ or research into patients with genetic disorders. Though most of them provided medical information about the disorder and the genetic risk to patients/families, they evaluated that their services were not sufficient for reasons such as a Jack of time. The physicians had little knowledge of genetic counselor, but those who had some experience of practice with and/or research into patients with genetic disorders felt the necessity of specialist on genetic counseling more frequently compared to those who did not. Whether they had any relevant experience or not, more than half of the respondents stated that non-physician genetic counselor was necessary.
We conclude that a genetic counselor system should be established as soon as possible, and also that education and enlightenment activities regarding genetic counseling are needed for physicians and all medical professionals.
A HNPCC (Hereditary N onpolyposis Colo rectal Cancer) family with a germline mutation of mismatch repair gene was reported. Two base pair deletion was detected at codon 568-569 in exon 11 of hMSH2 gene.
The proband of this family was a 21-year-old male who had an advanced sigmoid colon cancer with high aggregation of cancers, in his family. His maternal grandmother developed colon and ureteral cancers, and his mother developed colon and endometrial cancers. His maternal aunt also developed a colon cancer. Genetic testing of mismatch repair genes inclusive of hMSH2 and hMLHJ was performed to five family members with informed consents. Germline mutations of hMSH2 were recognized in three affected members and also in two of the asymptomatic family members, younger brother·of the pro band and a sun of affected aunt.
Peutz-Jeghers syndrome is an autosomal dominantly inherited disease with an increased risk for various malignancies. Recently, the STK11/LKB1 gene was identified as a causative gene for this syndrome, therefore, the genetic tesing is now available. We experienced a 38-year-old female patient with this syndrome. Under the informed consent, we performed the genetic testing of STK11/LKB1 gene on this patient, and detected a novel germline mutation on splice acceptor site of exon 8 of this gene. The offspring of this patient was also tested and was shown to harbour the same mutation. The usefulness of the genetic diagnosis for Peutz-Jeghers syndrome was discussed.
A proband, 42 year old male patient with positive fecal occult blood test, was found to have multiple adenomas in the entire colon by both barium enema and colonoscopic examinations.
Total colectomy with ileorectal anastomosis was performed under the diagnosis of familial adenomatous polyposis. Genetic analysis was carried out, revealing insertion of adenin at codon 158 in exon 4 of APC gene, causing nonsense mutation. Genetic diagnosis of AAPC was made. Genetic analysis of pro band's parents was also carried out, elucidating that the mother at the age of 68 had identical mutation of APC gene. She has no past history of colorectal cancer, however, very few tubular adenomas were found by subsequent colonoscopy. Pro band's father is not a mutation carrier.
AFAP is a clinical phenotype and it varies. This indicates that prophylactic surgery is not an appropriate treatment option in some of the AFAP cases.
Key words : familial adenomatous polyposis, APC gene, genetic diagnosis, phenotype, prophylactic total proctocolectomy.