Hi,
I don’t think you have to worry regarding your Ultrasound report. A Sebaceous cyst has nothing to do with breast cancer and doesn’t increase the risk of breast cancer in any way.
A “reactive" (Not malignant) lymph node enlarges mainly because it is trying to fight off an infection. Radiologists see lymph nodes day in and day out and know which lymph nodes are worrisome and which are not. I am sure your Radiologist has made recommendation concerning these benign findings.
All in all, I interpret your Ultrasound report as good news.
Best wishes…