When utilizing hypofractionated radiotherapy in the post mastectomy setting, are the nodal regions dose painted to a different dose or the same dose as the chest wall/reconstructed breast?
Our usual dose to the reconstructed breast/chest wall is 45 Gy in 18 fractions, requiring at least 95% of the PTV to receive 100% of the prescribed dose. The prescribed dose to internal mammary nodes (when treated) is the same, with a slightly lower acceptable dose (95% of the PTV receiving 95% of t...
- We use 40 in 15 and aim for similar coverage of the chest wall and nodal area (95 to 95).
- If OAR becomes a challenge, we do accept 90 to 90 also.
- In SAPHIRe study from MD Anderson, they aimed for 37.5 in 15 to RNI.
We follow what is done on Alliance A221505 and NCIC MA.39 and treat the regional nodes to the same dose as the chest wall. I know there are other data published in which the regional nodes receive a slightly lower dose.
In the FABREC trial, the chest wall was prescribed to 4256 cGy and the nodal field, 3990 cGy, recognizing that the lower axillary nodes are in the tangential fields. This nodal dose was reflective of what was prescribed in the START-B trial (when nodes were treated). In a higher-risk case, I would l...
I have been prescribing 4256 in 16 fractions to chest wall/reconstructed breast as simultaneous integrated boost while giving 4000 cGy in 16 fractions to nodal regions (IMN, Supraclavicular, and Axillary).