9.5x5.8cm sermona 4 weeks after lumpectomy ( seen on ct). it is uncomfortable but not so painful i need meds, also swollen & red. is treatment needed?

Get close: Follow up, make sure it's not infected. It doesn't sound like it.

Yes: You need to be seen in the office by your surgeon asap. A seroma this large needs to managed because there could be infection. Leaving a seroma this large will also cause great deformity and scar tissue. The goal for lumpectomy is to treat the cancer but should leave a breast with minimal deformity.