Survival time according to the year of recurrence and subtype in recurrent breast cancer

Abstract Background Survival for patients with recurrent breast cancer has improved over time due to the introduction of modern systemic therapy. The aim of this study was to determine the impact of subtype and the year of recurrence on the survival times of recurrent breast cancer. Methods Between 1979 and 2013, 813 patients who underwent initial treatment for primary breast cancer experienced recurrence. They were divided into two groups based on the year of recurrence; before 2000 and after 2001. Survival after recurrence was compared between these groups based on following criteria; subtypes, disease free interval (DFI), and dominant recurrent site. The median follow-up period after recurrence was 4.3 years. Results Survival improved significantly in the after 2001 group, and a significant improvement in survival was only seen in the HER2-enriched subtype. Multivariate analysis revealed that DFI, ER, HER2 status, dominant recurrent site and the Ki-67 index value were significant prognostic factors. In the HER2-enriched subtype, the year of recurrence, DFI and dominant recurrent site were significant independent factors. In the other subtypes, these factors were not correlated with survival. Conclusion Our study revealed that the survival rate of patients with only the HER2-enriched subtype significantly improved after recurrence. To prolong the survival time after recurrence of both luminal and triple negative subtypes, the development of novel targeting therapies to overcome refractory recurrent breast cancer is extremely important.