Conflicting reports on this topic have been published, as some have emphasised that HER3 and HER4 correlate with poor prognosis in human breast cancer (Bieche et al, 2003), while others have shown that HER3 and HER4 elevated expressions are associated with a better prognosis in this disease (Pawlowski et al, 2000). The gene discussed is ERBB4; the disease is breast carcinoma.