Mammogram occult cancer

A 55 year old lady finds a 1cm diameter left breast lump on self examination.

She had a normal screening mammogram 6 months ago.

Clinical examination confirms a 1cm diameter non-tender lump at 4 o'clock in the left breast.

New mammogram views are requested.

Side view (mlo)of breast

Top view (cc) of breast.

No abnormality is seen on these mammogram views.

What would you do next?

Answer: Request ultrasound imaging.

Ultrasound shows a 1cm solid,irregular mass.

Ultrasound-guided core biopsy showed features of an infiltrating duct carcinoma.

Comment: 20% of breast cancers will not show on a mammogram.

In the presence of a focal breast symptom investigation should include ultrasound and needle biopsy of any discrete solid lesion.