PRO B: evaluating the effect of an alarm-based patient-reported outcome monitoring compared with usual care in metastatic breast cancer patients—study protocol for a randomised con... oleh Maria Margarete Karsten, Friedrich Kühn, Therese Pross, Jens-Uwe Blohmer, Anna Maria Hage, Felix Fischer, Matthias Rose, Ulrike Grittner, Pimrapat Gebert, Julia Ferencz, Luis Pauler, Clara Breidenbach, Christoph Kowalski, on behalf of the PRO B Steering Board