Had breast mri , family history. a lump they think its benign lymph node. right away they want to do a mammogram . why would they do it if its that ?

Well benign lymph: Nodes are not palpable. Also on breast MRI they can tell if it was a lymph node by its shape and enhancement pattern. The problem is that lymph nodes have a washout pattern similar to that seen with cancer. I do not think the mammogram will help but you can do it on a 3d hologics digital unit. This needs followup.

Good Question!: Mammograms are of limited benefit in your 20's & not routinely ordered. I advise you to see a breast surgeon to help put all these puzzle pieces together. Something is not adding up based on the info you are providing--a benign-appearing intramammary ln usually requires no further evaluation. If anything, a directed ultrasound may corroborate these findings & allow easier follow-up.

Mam may prove it : An MRI cannot always tell a lymph node from a tumor, including cancer. A lymph node and some tumors light up intensely after contrast is injected. But a lymph node on a mammogram may have the classic appearance of a lymph node and if it is in the same place in the breast as the "lump" seen on the MRI the answer will be clear. Note: if you have a prior mammogram have them compare with this one!