Abstract P3-06-13: Transient increase in breast cancer risk after a full term pregnancy among African women

Background

African women affected by breast cancer (BC) have high parity with five children or more, are relatively young at first full term pregnancy (FFTP), are diagnosed at a young age and are often premenopausal at diagnosis. While several studies have assessed the role of reproductive factors for BC risk among African women, none of them have assessed whether there is dual effect of age at full term pregnancy (FTP). In this communications, using a large dataset from an on-going hospital-based case-control study, we examine the role of age at full term pregnancy on breast cancer risk among African women.

Methods

The study includes sites in Nigeria (University College Hospital, Ibadan), Cameroon (Yaoundé General Hospital) and Uganda (Breast Clinic of Mulago Hospital of Kampala). It was initiated in 1998 in Nigeria and extended to Cameroon and Uganda in 2011. Cases were consecutive females diagnosed with invasive BC. Controls were recruited from the community or within the hospital and have never being diagnosed with any cancer. Cases and controls were aged 18 years or more and gave informed consent. Full term pregnancy was defined as a pregnancy that lasted at least 7 months and included both live birth and stillbirth. Logistic regression models were used to assess the effects of age at first and second FTP, and their interaction with current age on BC risk. Age at menarche, parity, body mass index and hormone contraception use were included in the models.

Results

The study includes 1668 cases and 2399 controls recruited between 1998 and May 2013. Mean duration of live birth was 9 months (SD±0.52) and 8.8 months (SD±0.66) for a stillbirth. Overall, the mean age at FFTP was 23 years (SD±4.91) for both cases and controls. Compared to nulliparous women, parous women who had FFTP at 20 years have increased risk (OR = 1.59, CI 95%, 1.16-2.21) to develop BC in the year following the pregnancy. Up to 5 years following the FFTP, this OR is 1.38 (CI 95%, 1.06-1.80) while it is 0.77 (CI 95%, 0.62-0.95) 25 years later. This observation was also true for parous women who have had their FFTP at 25, 30, or 35 years. Moreover, a similar pattern was observed when comparing uniparous women to women with 2 or more children.

Conclusion

Our results show a transient increase in risk of BC after a full term pregnancy which declined and became protective over time. This observation is consistent with the effect of pregnancy on BC that has been described in other populations and may partially explain the current profile of breast cancer among African women.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-06-13.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.