D.J.A. Lobbezoo

Prognosis of metastatic breast cancer: are there differences between patients with de novo and recurrent metastatic breast cancer?

Background:We aimed to determine the prognostic impact of time between primary breast cancer and diagnosis of distant metastasis (metastatic-free interval, MFI) on the survival of metastatic breast cancer patients.Methods:Consecutive patients diagnosed with metastatic breast cancer in 2007–2009 in eight hospitals in the Southeast of the Netherlands were included and categorised based on MFI. Survival curves were estimated using the Kaplan–Meier method. Cox proportional hazards model was used to determine the prognostic impact of de novo metastatic breast cancer vs recurrent metastatic breast cancer (MFI ⩽24 months and >24 months), adjusted for age, hormone receptor and HER2 status, initial site of metastasis and use of prior (neo)adjuvant systemic therapy.Results:Eight hundred and fifteen patients were included and divided in three subgroups based on MFI; 154 patients with de novo metastatic breast cancer, 176 patients with MFI <24 months and 485 patients with MFI >24 months. Patients with de novo metastatic breast cancer had a prolonged survival compared with patients with recurrent metastatic breast cancer with MFI <24 months (median 29.4 vs 9.1 months, P<0.0001), but no difference in survival compared with patients with recurrent metastatic breast cancer with MFI >24 months (median, 29.4 vs 27.9 months, P=0.73). Adjusting for other prognostic factors, patients with MFI <24 months had increased mortality risk (hazard ratio 1.97, 95% CI 1.49–2.60, P<0.0001) compared with patients with de novo metastatic breast cancer. When comparing recurrent metastatic breast cancer with MFI >24 months with de novo metastatic breast cancer no significant difference in mortality risk was found. The association between MFI and survival was seen irrespective of use of (neo)adjuvant systemic therapy.Conclusion:Patients with de novo metastatic breast cancer had a significantly better outcome when compared with patients with MFI <24 months, irrespective of the use of prior adjuvant systemic therapy in the latter group. However, compared with patients with MFI >24 months, patients with de novo metastatic breast cancer had similar outcome.

In real life, one-quarter of patients with hormone receptor-positive metastatic breast cancer receive chemotherapy as initial palliative therapy: a study of the Southeast Netherlands Breast Cancer Consortium.

BACKGROUND The objective of this study was to present initial systemic treatment choices and the outcome of hormone receptor-positive (HR+) metastatic breast cancer. PATIENTS AND METHODS All the 815 consecutive patients diagnosed with metastatic breast cancer in 2007-2009 in eight participating hospitals were identified. From the 611 patients with HR+ disease, a total of 520 patients with HER2-negative (HER2-) breast cancer were included. Initial palliative systemic treatment was registered. Progression-free survival (PFS) and overall survival (OS) per initial palliative systemic therapy were obtained using the Kaplan-Meier method and compared using the log-rank test. RESULTS From the total of 520 patients with HR+/HER2- metastatic breast cancer, 482 patients (93%) received any palliative systemic therapy. Patients that received initial chemotherapy (n = 116) were significantly younger, had less comorbidity, had received more prior adjuvant systemic therapy and were less likely to have bone metastasis only compared with patients that received initial endocrine therapy (n = 366). Median PFS of initial palliative chemotherapy was 5.3 months [95% confidence interval (CI) 4.2-6.2] and of initial endocrine therapy 13.3 months (95% CI 11.3-15.5), with a median OS of 16.1 and 36.9 months, respectively. Initial chemotherapy was also associated with worse outcome in terms of PFS and OS after adjustment for prognostic factors. CONCLUSIONS A high percentage of patients with HR+ disease received initial palliative chemotherapy, which was associated with worse outcome, even after adjustment of relevant prognostic factors.

If there is no overall survival benefit in metastatic breast cancer: Does it imply lack of efficacy? Taxanes as an example

In recent years, new drugs have shown activity in metastatic breast cancer, but not always resulting in an overall survival benefit. This has led to discussions if such drugs, mainly expensive drugs, should be reimbursed especially when also not leading to improvement in quality of life. For that reason, we decided to systematically review taxane-based chemotherapy studies in early and metastatic breast cancer, to assess which factors may have caused the differential outcome. Taxanes did not improve survival in metastatic breast cancer trials, whereas they did so in early breast cancer trials. We questioned if the differential outcome of taxanes in metastatic breast cancer might be caused by the chosen comparator and study design. We noticed that in the majority of metastatic breast cancer studies taxanes were used as a substitute for other active cytotoxic drugs, mainly cyclophosphamide, whereas in early breast cancer studies taxanes were generally delivered in addition to a standard regimen. We conclude from our analyses that use of taxanes instead of other active drugs explains the lack of overall survival benefit in metastatic breast cancer trials. Further, our results suggest that cyclophosphamide is an important drug in the treatment of breast cancer, being as effective as optimally dosed taxanes and anthracyclines. By studying the different study designs and comparators in both settings, we were able to demonstrate their impact on efficacy endpoints. We conclude, therefore, that re-assessment of studies of drugs both assessed in metastatic and early breast cancer provides a new tool for improved understanding.

Real-world and trial-based cost-effectiveness analysis of bevacizumab in HER2-negative metastatic breast cancer patients : a study of the Southeast Netherlands Breast Cancer Consortium

INTRODUCTION The aim of our analysis was to assess the real-world cost-effectiveness of bevacizumab in addition to taxane treatment versus taxane monotherapy for HER2-negative metastatic breast cancer compared with the cost-effectiveness based on the efficacy results from a trial. METHODS A state transition model was built to estimate costs, life years (LYs) and quality-adjusted life years (QALYs) for both treatments. Two scenarios were examined: a real-world scenario and a trial-based scenario in which transition probabilities were primarily based on a real-world cohort study and the E2100 trial, respectively. In both scenarios, costs and utility parameter estimates were extracted from the real-world cohort study. Moreover, the Dutch health care perspective was adopted. RESULTS In both the real-world and trial scenarios, bevacizumab-taxane is more expensive (incremental costs of €56,213 and €52,750, respectively) and more effective (incremental QALYs of 0.362 and 0.189, respectively) than taxane monotherapy. In the real-world scenario, bevacizumab-taxane compared to taxane monotherapy led to an incremental cost-effectiveness ratio (ICER) of €155,261 per QALY gained. In the trial scenario, the ICER amounted to €278,711 per QALY gained. CONCLUSION According to the Dutch informal threshold, bevacizumab in addition to taxane treatment was not considered cost-effective for HER2-negative metastatic breast cancer both in a real-world and in a trial scenario.

The role of histological subtype in hormone receptor positive metastatic breast cancer : similar survival but different therapeutic approaches

Introduction This study describes the differences between the two largest histological breast cancer subtypes (invasive ductal carcinoma (IDC) and invasive (mixed) lobular carcinoma (ILC) with respect to patient and tumor characteristics, treatment-choices and outcome in metastatic breast cancer. Results Patients with ILC were older at diagnosis of primary breast cancer and had more often initial bone metastasis (46.5% versus 34.8%, P = 0.01) and less often multiple metastatic sites compared to IDC (23.7% versus 30.9%, P = 0.11). Six months after diagnosis of metastatic breast cancer, 28.1% of patients with ILC and 39.8% of patients with IDC had received chemotherapy with a longer median time to first chemotherapy for those with ILC (P = 0.001). After six months 84.8% of patients with ILC had received endocrine therapy versus 72.5% of patients with IDC (P = 0.0001). Median overall survival was 29 months for ILC and 25 months for IDC (P = 0.53). Materials and Methods We included 437 patients with hormone receptor-positive IDC and 131 patients with hormone receptor-positive ILC, all diagnosed with metastatic breast cancer between 2007–2009, irrespective of date of the primary diagnosis. Patient and tumor characteristics and data on treatment and outcome were collected. Survival curves were obtained using the Kaplan-Meier method. Conclusions Treatment strategies of hormone receptor-positive metastatic breast cancer were remarkably different for patients with ILC and IDC. Further research is required to understand tumor behavior and treatment-choices in real-life.