BACKGROUND: Many patients with breast cancer receive no benefit from their treatment. This has led to a search for novel therapeutic targets whose identification may facilitate a more tailored approach, thereby avoiding unnecessary toxicity. Of these, topoisomerase 2 alpha (TOP2A), located at the HER2/neu amplicon on chromosome 17, has generated particular interest because its expression has been shown to correlate with response to anthracycline-based therapies.
METHODS: We evaluated the relationship between TOP2A and its collocated gene, HER2/neu, and summarized the evidence for and against confining anthracycline-based therapies to those patients who demonstrate increased expression or amplification of these targets.
RESULTS: The emerging consensus supports the restriction of anthracyclines to those patients who are HER2/neu positive, with the evidence suggesting that alterations in the status of TOP2A are almost completely restricted to this group of patients.
CONCLUSIONS: It seems increasingly likely that response to anthracyclines is predicated on these alterations.