%0 Journal Article
%T Improved blood tests for cancer screening: general or specific?
%A Ian A Cree
%J BMC Cancer
%D 2011
%I BioMed Central
%R 10.1186/1471-2407-11-499
%X Several successful screening programmes are already well established, but these are currently applicable only to common cancers such as the faecal occult blood test [1] for colorectal cancer, mammography for breast cancer [2] and, of course, cervical cytology for cervical cancer and dysplasia, which is becoming ever more sophisticated [3,4]. Despite many attempts, blood tests have a less distinguished record. For instance, prostate-specific antigen screening is widely used despite its well-publicised problems [5]. It remains controversial and generates large numbers of papers every year (2, 032 were indexed in PubMed through 2010 using the search terms 'screening', 'prostate specific antigen' and 'cancer'). Many other tumour markers have been described, usually in relatively small studies, and few make it through to clinical use. Cancer antigen 125 (CA 125) was first described as a marker of ovarian cancer in 1981 [6] and is still being evaluated as a potential screening test [7,8].Despite its history, blood-based screening for cancer remains attractive, as it could provide inexpensive testing that would arguably be more acceptable to patients and easily incorporated into an annual checkup, which might include cholesterol and other assays of general health. This idea was judged too risky to be funded when put forward in 2005, but six years later, the recent review along similar lines by Hanash et al. [9] has shown how fast the necessary underlying science is advancing. There is no doubt that cancers have characteristics that could be detected by performing blood-based screening tests (Figure 1). In 2000, Hanahan and Weinberg [10] published their seminal paper describing the Hallmarks of Cancer, and many authors since then have described changes in blood related to these characteristics. Hanahan and Weinberg pointed out that cancer cell growth is the result of self-sufficiency in growth signals and insensitivity to antigrowth signals. Such signals are often mediated
%U http://www.biomedcentral.com/1471-2407/11/499