%0 Journal Article
%T Prospective study of Outcomes in Sporadic versus Hereditary breast cancer (POSH): study protocol
%A Diana Eccles
%A Sue Gerty
%A Peter Simmonds
%A Victoria Hammond
%A Sarah Ennis
%A Douglas G Altman
%A the POSH steering group
%J BMC Cancer
%D 2007
%I BioMed Central
%R 10.1186/1471-2407-7-160
%X The study is a prospective cohort study recruiting 3,000 women aged 40 years or younger at breast cancer diagnosis; the recruiting period covers 1st June 2001 to 31st December 2007. Written informed consent is obtained at study entry. Family history and known epidemiological risk data are collected by questionnaire. Clinical information about diagnosis, treatment and clinical course is collected and blood is stored. Follow up data are collected annually after the first year. An additional recruitment category includes women aged 41 to 50 years who are found to be BRCA1 or BRCA2 gene carriers and were diagnosed with their first breast cancer during the study recruiting period.Power estimates were based on 10% of the cohort carrying a BRCA1 gene mutation. Preliminary BRCA1 and BRCA2 mutation analysis in a pilot set of study participants confirms we should have 97% power to detect a difference of 10% in event rates between gene carriers and sporadic young onset cases. Most of the recruited patients (>80%) receive an anthracycline containing adjuvant chemotherapy regimen making planned analyses more straightforward.Less than 5% of breast cancers diagnosed in the UK are diagnosed in women aged 40 years or younger although there is a rapid increase in the incidence from about 35 years of age[1].Published retrospective studies suggest that early age at onset of breast cancer (below 35 years) is a poor prognosis factor; high grade and oestrogen receptor (ER) negative tumours appear to be more frequent in younger women[2,3]. Breast cancer arising due to a high penetrance genetic predisposition gene such as BRCA1 or BRCA2 occurs at younger average age than breast cancer in the general population and a higher proportion of young onset cases will have a genetic predisposition than breast cancer cases in general. Family history is still the most important indicator of an underlying inherited predisposition [4]. However BRCA1 and BRCA2 may account for less than 40% of all familia
%U http://www.biomedcentral.com/1471-2407/7/160