Administering chemotherapy cycles closer together (ie, every 2 weeks instead of every 3) improves survival for premenopausal women with breast cancer. The regimen, called dose-dense adjuvant chemotherapy, was not found to increase risk for treatment-induced early menopause.1
These findings, presented at the 10th European Breast Cancer Conference, will help younger women with breast cancer and their doctors make better-informed decisions about chemotherapy regimens as well as other treatments such as surgery, hormone therapy, and radiotherapy.
“Our results confirm the superiority of dose-dense chemotherapy as compared to standard interval regimens in premenopausal patients at higher risk of relapse, and its use should be implemented in Europe, as it is in the United States,” said Matteo Lambertini, MD, a medical oncologist at IRCCS Azienda Ospedaliera Universitaria, San Martino Istituto Nazionale per la Ricerca sul Cancro, National Institute for Cancer Research, Genoa, Italy, and at the Institut Jules Bordet, Brussels, Belgium.
Right now, European treatment guidelines have no clear recommendations, whereas dose-dense chemotherapy is used more often in the United States. No data was available on whether dose-dense chemotherapy triggered early menopause and its associated complications, including infertility.
This research involved a meta-analysis of 2 large randomized phase III clinical trials that compared dose-dense regimen of adjuvant chemotherapy (every 2 weeks) with the standard interval regimen (every 3 weeks). The studies included 3305 patients, 1549 of whom were premenopausal—these were the patients the analysis was based on—average age, 44 years.
Overall survival at 10 years was significantly improved in the patients who received dose-dense adjuvant chemotherapy compared with those who received standard interval chemotherapy. In addition, dose-dense regimen did not increase the risk for treatment-induced amenorrhea.
Dose-dense chemotherapy seemed to be effective irrespective of hormone receptor status: 10-year overall survival was improved by 22% in patients with hormone receptor (HR)-positive tumors and by 35% in patients with HR-negative tumors.
Given the psychosocial impact of chemotherapy, particularly regarding treatment-induced amenorrhea and the consequent loss of ovarian function, Lambertini stressed the importance of trying to maintain ovarian function and fertility in young patients with breast cancer who are candidates for chemotherapy during their reproductive years.
1. Lambertini M, Ceppi M, Bruzzi P, et al. Dose-dense adjuvant chemotherapy, treatment-induced amenorrhea and overall survival in premenopausal breast cancer patients: a pooled analysis of the MIG1 and GIM2 phase III studies. Oral presentation at: 10th European Breast Cancer Conference; March 9-11, 2016; Amsterdam, The Netherlands. Abstract 5.