The irradiated breast: impact on the patient and potential solutions for skin toxicity

This thesis evaluates the long-term consequences of breast cancer treatment and the impact of breast cancer on quality of life. Breast cancer treatment consists of (a combination of) surgery, chemotherapy, endocrine therapy and radiotherapy. Radiotherapy plays an important role to decrease breast cancer recurrence. Radiotherapy may result in late radiation toxicity, which is characterized by (a combination of) breast pain, impaired arm mobility, breast fibrosis, impaired cosmetic outcome and edema in the breast or arm. Approximately 16% of the breast cancer patients experience late radiation toxicity. In comparison to patients without late radiation toxicity, these patients reported lower quality of life, physical functioning and social functioning. A systematic review showed that higher radiotherapy dose and an increased radiotherapy volume was associated with late radiation toxicity. This emphasizes the importance to focus on new radiotherapy techniques, such as hypofractionation and partial breast irradiation. Finally, this thesis showed that hyperbaric oxygen therapy may decrease late radiation toxicity. In a single arm cohort study with 1005 patients with late radiation toxicity showed that patients reported decreased breast and arm symptoms and less pain after hyperbaric oxygen therapy. However, a randomized controlled trial where symptoms of late radiation toxicity will be compared between patients receiving hyperbaric oxygen therapy and usual care needs to confirm these results. For that reason, a study protocol using a trial within cohorts design was written and is currently being executed.