International guidelines for management of metastatic breast cancer (MBC) from the European School of Oncology (ESO)–MBC Task Force: Surveillance, staging, and evaluation of patients with early-stage and metastatic breast cancer

In clinical practice, the surveillance and follow-up of patients with breast cancer (BC) is quite variable. At the 7th European Breast Cancer Conference, the ESO-MBC Task Force convened a series of lectures, followed by open debate, on the use of physical examination, imaging, and laboratory tests in patients with early-stage BC, and for restaging evaluations and follow-up among patients with MBC. Based on the available data, the Task Force recommends against intensive, routine radiologic or blood-based surveillance (with the exception of mammography) in patients with early-stage BC. As systemic therapies for MBC continue to improve, this question might be re-visited in the context of a carefully controlled clinical trial in specific BC subtypes. For patients with MBC, response to therapy should generally be assessed 2–3 months after initiation of treatment, and thereafter every 2–4 months for endocrine therapy or every 2–4 cycles for chemotherapy, depending on the dynamics of the disease, the location and extent of metastatic involvement, and type of treatment. Additional testing should be performed irrespective of the planned intervals if progression of disease is suspected (e.g. in the case of specific symptoms). Use of tumor markers is not recommended for surveillance of early-stage patients, but may be helpful in monitoring response to therapy in patients with metastatic disease. However, change in tumor markers alone should not be used for decision-making. Moving forward, enhanced efforts to document quality of life over time should be made in order to more fully evaluate the risk/benefit ratio of available options.