enlarged lymph node in reconstructed breast

spainer

I had a skin sparing/nipple sparing mastectomy in Nov 2013 after DCIS was found throughout my left breast. I underwent reconstruction in Feb 2014. One year later (this Feb) I found a lump in the reconstructed side (small, pea-sized) just under my skin. I figured it was scar tissue, as did my surgeon's nurse practitioner, but ultimately had a MRI that determined it wasn't scar tissue, then was sent for ultrasound, and finally a fine needle biopsy. It was a tricky biopsy as the mass was on the surface of the implant. The result was that it was a benign lymph node. That was in March, and it is still there, about the same size. While I'm not super worried, I am wondering if anyone has experienced something similar? I know there was some tissue left below the skin, but is it common that there are lymph nodes left there? I have read women's accounts of initial biopsies missing things, and although I know the chance of recurrence post-mastectomy is something like 1-2%, I just thought I'd canvas for other's opinions. Thanks!