I would have a mammogram retest before having a biopsy. A biopsy is an invasive procedure. Minor, to be sure, but invasive nonetheless.
Hi,
It happens sometimes when nodules don't appear on ultrasound or mammogram.Each test has it's limitations and what it can pick up.For example an ultrasound is better at differentiating between a lump that is solid or fluid filled.A solid mass may not show up on ultrasound and when this happens,it is usually recommended that the lump be biopsied to see what it is exactly.
Try not to worry too much about this finding and keep in mind that most lumps detected in the breasts are no cause of concern.
A biopsy is a simple procedure which could be a little uncomfortable but not painful.Fluid will come out if it's a cyst and if not, tissue in the needle can be examined under the microscope in order to make a definitive diagnosis.
Please,let us know how things are proceeding by adding your comment below the answer/s you have received.Thank you.
Best wishes and hoping for benign results.