Treatment Holiday May Be Ill-Advised in Patients With Advanced Breast Cancer: Presented at ESMO Breast

By Jenny Powers

BERLIN -- May 5, 2019 -- Patients with human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer who were given a treatment break showed poorer survival rates than those who received continuous therapy, researchers reported here at the 2019 European Society of Medical Oncology Breast Congress (ESMO Breast).

“For first and second lines of treatment, the survival was better with continuous treatment,” said Frans Erdkamp from Zuyderland Medical Center in Sittard-Geleen, the Netherlands.

Combined median overall survival (OS) in 420 patients on first- and second-line therapy was 20.3 months for patients on an intermittent schedule compared with 23.0 months for those receiving continuous treatment (hazard ratio [HR] = 1.93).

The median combined progression-free survival (PFS) in this cohort was 14.6 months compared with 16.6 months in patients on intermittent versus continuous treatment (HR = 1.59).

In the 270 patients initiating second-line treatment, 131 patients receiving intermittent therapy demonstrated median PFS of 3.5 compared with 5.0 months in 139 patients on continuous treatment (HR = 1.04). Median OS in the second-line cohort was 10.6 versus 12.0 months, respectively (HR = 1.64).

“We were a little surprised at the findings running contrary to our hypothesis,” said co-author Monique Bos, MD, Erasmus University Medical Centre, Rotterdam, the Netherlands. “In explaining therapy schedules to patients we tend to suggest that a ‘holiday’ -- by nature of the word -- might be beneficial, but this was not the case.”

The phase 3 Stop&Go study randomised 420 patients with advanced HER2-negative breast cancer to either an intermittent schedule consisting of 4 cycles, a treatment holiday, and then another 4 cycles or to a continuous schedule of 8 cycles administered consecutively. Paclitaxel plus bevacizumab was given as first-line treatment and capecitabine or non-pegylated liposomal doxorubicin was given as second line treatment.

Funding for this study was provided by F. Hoffmann-La Roche Ltd.

[Presentation title: Intermittent Versus Continuous Chemotherapy Beyond First-Line for Patients With HER2-Negative Advanced Breast Cancer (BOOG 2010-02). Abstract 158P_PR]

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