Hi, radiation oncologist here. In general it is a challenge to get summary data from individual radiation plans. For instance, in your example, where the chest wall and axilla were treated, those would have been two different treatment areas during the same treatment course and generally treated on the same days. So the patient might get 25 sessions, where axilla and chest wall were both treated in each session. You would not want to add up the dose that chest wall and axilla got to create a total dose (in your example, 50+45=95 Gy) because no part of the body got 95 Gy and that total would be misleading.
For other situations like a boost where the breast gets 50 Gy and then a 10 Gy boost, it is OK to add up the doses to get the total dose of 60 Gy to the breast.
You can usually figure out the total radiation dose to various areas by looking in the oncology information system like Aria/Mosaiq at a combination of the radiation plans (with first/last treatment dates, site name, etc.) and prescriptions (site name, target name, linked plans), but this requires some specialized expertise.
I don’t have a lot of answers, just wanted to make sure you understood the challenges.