Survival and prognostic factors in oligometastatic breast cancer
Annemiek van Ommen-Nijhof,
Tessa G. Steenbruggen,
Laura Capel,
Michel Vergouwen,
Marie-Jeanne T. Vrancken Peeters,
Terry G. Wiersma,
Gabe S. Sonke
Affiliations
Annemiek van Ommen-Nijhof
Department of Medical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands
Tessa G. Steenbruggen
Department of Medical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands; Department of Internal Medicine, St Antonius Hospital, PO Box 2500, 3430 EM, Nieuwegein, the Netherlands
Laura Capel
Department of Internal Medicine, St Antonius Hospital, PO Box 2500, 3430 EM, Nieuwegein, the Netherlands
Michel Vergouwen
Department of Biometrics, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands
Marie-Jeanne T. Vrancken Peeters
Department of Surgical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands; Department of Surgery, Amsterdam University Medical Center, PO Box 22660, 1100 DD, Amsterdam, the Netherlands
Terry G. Wiersma
Department of Radiation Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands
Gabe S. Sonke
Department of Medical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands; Department of Medical Oncology, Amsterdam University Medical Center, PO Box 22660, 1100 DD, Amsterdam, the Netherlands; Corresponding author. Department of Medical Oncology, The Netherlands Cancer Institute - Antoni van Leeuwenhoek, PO Box 90203, 1006 BE, Amsterdam, the Netherlands.
Background: Guidelines for oligometastatic breast cancer (OMBC) propagate multimodality treatment including polychemotherapy and local ablative treatment (LAT) of all lesions. The aim of this approach is prolonged disease remission, or even cure. Long-term outcomes in OMBC and factors associated with prognosis are largely unknown, due to the rarity of this condition. We report overall survival (OS), event-free survival (EFS), and prognostic factors in a large real-world cohort of patients with OMBC. Methods: Patients with breast cancer and 1–3 distant metastatic lesions, treated in the Netherlands Cancer Institute between 1997 and 2020, were identified via text mining of medical files. We collected patient, tumor and treatment characteristics. The Kaplan-Meier method was used to calculate OS and EFS estimates, and Cox regression analyses to assess prognostic factors. Results: The cohort included 239 patients, of whom 54% had ERpos/HER2neg, 20% HER2pos and 20% triple negative disease. Median follow-up was 88.0 months (95% confidence interval (CI) 82.9–93.1) during which 107 patients died and 139 developed disease progression/recurrence; median OS was 93.0 months (95%CI 66.2–119.8). Factors associated with OS in multivariable analysis were subtype, disease-free interval and radiologic response to first-line systemic therapy; LAT was associated with EFS, but not OS. Conclusions: In this large real-world cohort of patients with OMBC, OS and EFS compare favorably to survival in the general MBC population. Radiologic complete response to first-line systemic therapy was associated with favorable OS and EFS, indicating the importance of early optimal systemic therapy. The value of LAT in OMBC requires further study.
