Histologically confirmed adenocarcinoma of the breast
Assumed clinical or pathological stage III (TNM) breast cancer
Breast tumor must be:
* HER2-negative: i.e. either score 0 or 1 at immunohistochemistry or score 2 at immunohistochemistry and negative at in situ hybridization (ISH, CISH or FISH)
* Hormone receptor negative i.e. an estrogen receptor (ER) of \<10% and progesterone receptor (PR) of \<10%.; or in case of a histological grade III tumor an ER of \<50% and a PR of \<50%.
Patients are planned to receive the complete standard of care in the Netherlands; neo-adjuvant chemotherapy according to local practise
Participating patients have to be able to use a mobile phone, tablet, laptop and/or computer and understand the Dutch language
You may not be if
Evidence of distant metastases. Staging examinations should have been performed according to Dutch national guidelines.
Patients who are only treated systemically in the adjuvant setting
Participation in another clinical study with an treatment intervention during the course of this study.
