Authors' objectives:

The objective of this report was to perform a systematic review of the current literature and an assessment of the scientific evidence on the following issue: Does HRT increase or decrease the risk of breast cancer recurrence or breast-cancer death in patients with previous breast cancer?

Authors' results and conclusions: Of the 2659 articles retrieved, only eight were considered relevant to the question. Of these two were of moderate quality, and were included as evidence. The remaining six were given a lower quality score by the expert group and were excluded. All studies were observational and no randomised controlled trials (RCTs) articles could be found. Although neither of the studies indicated an increased risk of breastcancer recurrence, the currently available documentation is too weak to allow firm conclusions to be drawn in either direction. Several well-designed RCTs addressing the issues raised in the present report are in progress. However, the results from these studies will not be available for some time. In the meantime, it would be beneficial to the patients if clinicians could agree upon a common information strategy. The need for more research in this area was clearly revealed, and should be given substantial attention and support. Women who are eligible for study participation should be encouraged to enrol in the ongoing studies.

Authors' recommendations: There are theoretical reasons to assume adverse effects of HRT in patients previously treated for breast cancer. Clinical observational studies indicate the opposite, however, with low evidence strength. Ongoing randomised controlled trials (RCTs) will provide the answers in a few years. In the meantime, clinicians should seek to give consistent information to their patients. Furthermore, women who seek HRT should be encouraged to participate in the ongoing trials.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.nokc.no/

Year Published: 2003

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Norway

Organisation Name: Norwegian Institute of Public Health

Contact Address: Universitetsgata 2, Postbox 7004 St. Olavs plass, NO-0310 Oslo NORWAY. Tel: +47 23 25 50 00; Fax: +47 23 25 50 10;

Contact Name: Berit.Morland@nokc.no, dagny.fredheim@nokc.no

Contact Email: Berit.Morland@nokc.no, dagny.fredheim@nokc.no

Copyright: The Norwegian Knowledge Centre for the Health Services