title: The efficacy of second-line hormone therapy for recurrence during adjuvant hormone therapy for breast cancer.
abstract: OBJECTIVE
  The recurrence of breast cancer during adjuvant hormone therapy is often targeted by second-line hormone therapy. However, there has been a lack of prior success with such treatments. We retrospectively investigated the efficacy of subsequent hormone therapy.
  
  
  METHODS
  Patients who underwent breast cancer surgery between 2006 and 2012 at our institution were investigated.
  
  
  RESULTS
  A total of 20 patients developed recurrence during adjuvant hormone therapy. There were four patients with luminal A, seven with luminal B and six with luminal HER2 tumors, respectively. Twelve patients received subsequent hormone therapy, and eight patients received chemotherapy. Subsequent hormone therapy produced one partial response (PR), two long stable disease (SD), one SD and five progressive disease (PD). A clinical benefit (CB) was obtained by 33%. Subsequent chemotherapy produced one complete response (CR), two PRs, one long SD and two PD, resulting in a CB in 66%. Among those who received any hormone therapy, the best responses were two PR, three long SD and one SD. A CB was obtained by 38%, while seven patients did not have any CB from hormone therapy. Meanwhile, the best responses to chemotherapy were two CRs, four PRs, three SD and two PD, thus resulting in a CB in 72%. All luminal A cases obtained a long SD or SD with hormone therapy. However, the CB of hormone therapy for non-luminal A cases was only 30%.
  
  
  CONCLUSIONS
  The efficacy of hormone therapy for recurrence during adjuvant hormone therapy is poor, and when selecting therapy for such patients, the breast cancer subtype should be taken into account.
authors.affiliation: Department of Breast Surgery, Gifu Prefectural General Medical Center, 4-6-1, Noishiki, Gifu, Gifu 500-8717, Japan.
authors.forename: Ryutaro
authors.initials: R
authors.lastname: Mori
authors.affiliation: Department of Breast Surgery, Gifu Prefectural General Medical Center, Gifu, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Nagao
keywords: breast neoplasms; drug resistance; hormone