There is currently no high evidence data proofing that one particular fractionation regimen provides advantages over others in the most common scenarios, for example castration-resistant prostate cancer, endocrine responsive breast cancer, Her2 positive breast cancer, EGFR wild-type non-small cell lung cancer, clear cell kidney cancer treated with angiogenesis inhibitors etc. In certain situations, it might be advantageous that shorter courses of radiotherapy interfere less with administration dates of systemic treatment. Here, ERBB2 is linked to breast cancer.