Mammograms will miss approximately 10 to 15 percent of all breast cancers, and so a negative mammogram does not completely exclude the possibility of breast cancer. Having said that, most breast and armpit lumps will not turn out to be cancer (but some will...).

An ultrasound of this area would be a logical next step. If the ultrasound reveals a solid mass, then the Radiologist can also perform an ultrasound-guided needle biopsy of the mass to assist in making a diagnosis. If the ultrasound is normal, but a palpable mass is still present, then excisional biopsy of the lump may be considered after consultation with a surgeon.

Sincerely/ Robert A. Wascher, MD, FACS

http://doctorwascher.com