CancerConnect News: Survival without relapse for patients with early-stage breast cancer has improved significantly over the past 30 years, particularly among women with HER2-positive disease. These findings were recently published in the Journal of Clinical Oncology.
Cancer is considered relapsed when disease returns after it has been in remission following treatment, meaning that signs and symptoms have disappeared. Preventing relapse—or achieving relapse-free survival—is of course an important goal of treatment.
Researchers with the British Columbia Cancer Agency recently measured changes in patterns of relapse in breast cancer over the past 30 years. Specifically, they looked at relapse according to estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) status, or biomarker status.
Patients involved in the study were divided into two groups. Group one had been diagnosed with Stage I, II, or III breast cancer between 1986 and 1992; group two had been diagnosed between mid-2004 and 2008. All patients had a known ER and HER2 status. Patients in group one were matched for comparison with patients in group two according to stage, grade and ER and HER2 status. The researchers assessed rate of relapse according to biomarker status.
Each group contained just over 3,500 women. Patients in group one were matched with comparable patients in group two. Among both groups combined biomarker status was as follows: 70% were ER positive/HER2 negative, 7% were ER positive/HER2 positive, 7% were ER negative/HER2 positive, and 16% were ER negative/HER2 negative.
Overall, patients in group two (those diagnosed between mid-2004 and 2008) had less risk of relapse compared with those in group one (those diagnosed between 1986 and 1992). The risk of relapse was reduced by 50%. Patients in the later-diagnosed group had a lesser risk of relapse if their breast cancer was HER2 positive or ER negative/HER2 negative. Group two also had a lower risk of death compared with group one.
According to these findings, breast cancer patients have begun experiencing increasingly more frequent relapse-free survival over the past 30 years. Patients with all types of breast cancer are experiencing these improved outcomes, but particularly those whose disease is HER2 positive or ER negative/HER2 negative. This information can advanced early breast cancer treatment by helping doctors and patients make treatment decisions and researchers plan clinical trials.
Reference: Cossetti RJD, Tyldesley SK, Speers CH, et al. Comparison of Breast Cancer Recurrence and Outcome Patterns Between Patients Treated From 1986 to 1992 and From 2004 to 2008. Journal of Clinical Oncology [early online publication]. November 24, 2014, doi: 10.1200/JCO.2014.57.2461.