Hereditary breast cancer in Northern Ireland.

The aim of this investigation was to document hereditary breast cancer in Northern Ireland. Family history details from over nine hundred women were obtained by postal survey and one hundred and twenty nine home visits were carried out to collect pedigree information. The families documented varied in the number of affected women from three, which was the minimum criteria for inclusion, to a maximum of nine and many families described other features of hereditary disease such as bilateral breast cancer, ovarian and gastrointestinal malignancies.     

Hereditary site-specific colon cancer in a Canadian kindred.

A large kindred with colorectal cancer unaccompanied by polyposis coli and characterized by autosomal dominant inheritance has been identified in eastern Canada. Ten family members from three successive generations have presented 17 documented colorectal cancers. The clinical features of the kindred are characteristic of hereditary site-specific colon cancer (HSSCC) (Lynch syndrome I): absence of multiple polyposis, autosomal dominant inheritance, onset of colorectal cancer at an early age and a high incidence of synchronous and metachronous colorectal cancers. A unique feature of this family is the high incidence of sporadic adenomatous polyps in affected members and their relatives. Patients with HSSCC have been managed by means of segmental colectomy followed by annual colonoscopic surveillance. All five patients with localized (Dukes' stage A or B) cancer at initial diagnosis were alive and free of disease after 2 to 12 years of follow-up, although three had required further colonic resection for metachronous carcinomas. Five young family members without cancer have had sporadic adenomatous polyps removed and are being followed with annual colonoscopy. It is not known whether polypectomy will alter the subsequent incidence of colon cancer. Subtotal colectomy is recommended for patients with HSSCC because of the high incidence of multiple lesions. An aggressive screening protocol, including colonoscopy, is recommended for all adult first- and second-degree relatives of patients with HSSCC. Identification of a biomarker, which is currently being sought in this kindred, would help identify those at greatest risk of development of cancer and allow earlier intervention.     

The dilemma of hereditary prostate cancer.

The observation that a family history of prostate cancer significantly increases a man's risk of the disease (see pages 895 to 900 of this issue) highlights many of the ethical, emotional and pragmatic controversies in medical circles concerning the management of this common form of cancer. This editorial describes a patient's personal dilemma when he learns that his brother is dying of prostate cancer, a dilemma that illustrates the potential harms and benefits of early detection and treatment. Current evidence does not justify screening asymptomatic men for prostate cancer, but many Canadian physicians do practise early case detection for some patients with a high risk of the disease. Men with a family history of prostate cancer must be informed by their physicians about the known and unknown risks and benefits of early detection and treatment, before they undergo the cascade of diagnostic and therapeutic procedures associated with prostate cancer.     

Etiology of breast cancer. II. Epidemiologic aspects

The epidemiology of breast cancer is reviewed with particular emphasis on its etiology. A number of studies suggest that differences in breast cancer incidence are associated with differences in marital status, number of pregnancies, age at menarche, age at menopause, height and weight, socioeconomic status, geographic location and residence. However, in no case is the evidence adequate to establish a “cause and effect” relationship. The genetic component of these associations may be of primary importance, while other conditions such as marital status are probably indirect reflections of the operation of more fundamental factors.

There is a general consensus that endocrine factors play an important part in mammary cancer occurrence. At present, the association between breast cancer and the presence of the virus-like (type B) particles in human milk is not established.

     

Etiology of breast cancer I. Genetic aspects

The subject of breast cancer is reviewed with particular emphasis on the genetic aspect of its etiology. A number of studies using various approaches gave the same results: the familial form occurs earlier and there is a higher risk in female members of the breast-cancer families. An association between breast cancer and cancer of certain other sites among women is reported. Cytogenetic studies of “cancer families” revealed increased frequency of aneuploidy in some members. However, the role of chromosome abnormalities in carcinogenesis is still not clear.     

前列腺癌患者前列腺癌基因3的表达

目的评价前列腺癌基因3（PCA3）在前列腺癌诊断中的临床应用价值。方法选取我院2009年11月~2010年11月收治的30例前列腺癌（前列腺癌组）、22例前列腺增生（前列腺增生组）患者及12例健康男性（对照组）,采用逆转录聚合酶链式反应方法检测其外周血中PCA3 mRNA表达情况。结果对照组及前列腺增生组外周血标本中未见PCA3 mRNA阳性表达,而前列腺癌组患者外周血标本中PCA3 mRNA阳性率为99.3%（28/30）,差异有高度统计学意义（χ2=65.283,P〈0.01）。结论前列腺癌中PCA3 mRNA有明显组织特异性的阳性表达,有望成为前列腺癌诊断的新肿瘤标志物。