What treatment planning challenges do you consider when treating a woman with synchronous bilateral breast cancers?

I think this depends on the scenario and treatment choices:

1. Bilateral early stage cancers- can consider partial breast techniques bilaterally and avoid concerns about overlap

2. Bilateral early stage cancer- whole breast irradiation, I like 1-2 cm between medial tangents to avoid potential double treatment. Not always possible based on anatomy of breasts but at a minimum 1 cm.

3. Bilateral locally advanced- Most challenging when both IM nodes need to be treated as it can be challenging to get partially wide tangents without medial tangents overlapping. Can consider shorter tangents with medial electron to cover bilateral IM's and feather the junctions. Alternatively, IMRT.

If using DIBH/breathhold, make sure you use on both sides to ma...