Long-term disease control with capecitabine in advanced breast cancer.

Abstract

e12566 Background: Capecitabine is an active agent in the treatment of advanced breast cancer (ABC). It is commonly administered at the approved dosage of 1250 mg/m2 twice daily for 2 weeks followed by 1 week rest period. Methods: The study population included 162 pts retrospectively analyzed with ABC treated with capecitabine between 2006 and 2015 at our Institute. Capecitabine was given 14 day on,7 day off cycle at a daily dose of 1900 mg/m2, a modified schedule used to minimize side effects. The objective were overall response rate (ORR), median duration of treatment (MDT) progression-free survival (PFS), overall survival (OS). Results: The median age was 64 years (range 33-89). Pts with hormone receptor positive ABC were 133 (82%), 6 (4%) had HER-2 positive disease and 29 (18%) a triple negative profile. One hundred and thirty eight (85%) had already received chemotherapy in adjuvant and/or metastatic setting; anthracycline and taxanes were given in 64 pts (40%), anthracycline in 60 pts (37%) and taxane in 4 pts (2%), 9 pts (6%) received other regimens of chemotherapy. Twenty-five pts (15%) were chemo-naive. One hundred and thirty-three pts (82%) received endocrine therapy. Sixty-four pts (38%) had predominantly non-visceral metastases, 26 pts (16%) exclusive visceral involvement, 72 (44%) exhibited both characteristics. ORR was 58% (CR = 2%, PR = 16% SD = 40%) and MDT was 6.9 months. The median PFS and OS were 6.9 months and 21 months, respectively. We defined as “long responders” 19 pts (12%) with disease control interval > 24 months and, among them, as “very long responders”, 9 pts (6%) who exceeded 36 months. Efficacy was unrelated to biological profiles, sites of metastasis or previous therapies. No grade 3 and 4 adverse events occurred. Conclusions: Our results show that in pts with ABC a lower dose of capecitabine has a good toxicity profile and similar overall response rate and survival data in comparison to the approved dose. In addition, we identified a subset of long and very long responders but further studies are warranted to evaluate clinical/biological predictors of a long-term response.