Add-On Adjuvant Capecitabine Improves Outcomes in Triple Negative Breast Cancer
By Brian Hoyle
SAN ANTONIO, Tex -- December 13, 2016 -- The addition of capecitabine to standard adjuvant chemotherapy provides improvements in both disease-free survival (DFS) and overall survival (OS) in patients with triple negative breast cancer (TNBC), according to a study presented here at the 39th Annual San Antonio Breast Cancer Symposium (SABCS).
“Addition of capecitabine is a reasonable option for patients with early stage TNBC,” said Akina Natori, MD, Princess Margaret Cancer Centre, Toronto, Ontario, on December 9.
The meta-analysis was prompted by the known effectiveness of capecitabine for metastatic breast cancer counterbalanced by the hazy knowledge of the drug’s benefit in early breast cancer. The researchers scoured the literature and conference proceedings for RCTs that involved a comparison of standard chemotherapy with cyclophosphamide, methotrexate, 5-fluorouracil, and anthracycline-based regimens, or anthracycline/taxane that also included or did not include neoadjuvant capecitabine.
The 374 studies that were initially identified were whittled down to 8 studies that included 9,302 patients. Two RCTs (CALGB 49907 and ICE II-GBG 52) involved capecitabine as an adjuvant and as a replacement for other drugs. The other trials (FinXX, GEICAM 2003-10, US Oncology 01062, GeparQuattro, Ohno et al. 2013, and CREATE-X) used capecitabine as an add-on in the adjuvant or neoadjuvant setting.
In unselected patients, capecitabine did not influence DFS (hazard ratio [HR] = 0.99; P = .93) or OS (HR = 0.90; P = .36). When used in place of standard therapy, capecitabine significantly improved OS compared to standard treatment (HR = 0.83 vs 1.63).
A significant difference in DFS was evident when capecitabine was given in addition to standard therapy, compared with replacing standard therapy (HR = 0.83 vs 1.63; P = .002).
The addition of capecitabine to standard chemotherapy significantly improved DFS in TNBC vs non-TNBC (HR = 0.72 vs 1.01; P = .02), and a benefit with OS that was confirmed in a mega-regression this association with OS (r = -0.967; P = .007).
The benefits came with the added burdens of increased grade 3/4 diarrhoea (odds ratio [OR] = 2.33; P < .001) and hand foot syndrome (OR = 8.08; P < .001). The increased drug-related toxicity was associated with more frequent treatment discontinuation (OR = 3.80; P < .001).
For patients with TNBC who can tolerate the added toxicity of capecitabine, the benefits of its use in the adjuvant setting can be pronounced.
[Presentation title: Capecitabine in Early Breast Cancer: a Meta-Analysis of Randomized Controlled Trials. Abstract P5-14-05]