Been diagnosed with breast cancer, for which lumpectomy & radiation suggested. I have pmle. Will this be a problem when it comes to radiation?

Gamma not same as UV. Gamma radiation is not the same as uv radiation but it is best to discuss with your radiation oncologist.
PMLE appears . To be immune mediated. I know of no reports of reactions with megavoltage energy radiotherapy that would be advised for breast conservation. The size of the lesion, nodes, er/pr/her-2-neu status would help. Ordinarliy I am *not* an advocate of "partial breast rt", you might discuss this with your radiation oncology consultant.
Oncologist . Your oncologist will guide your through every step.