You probably know what a mammogram is – in fact, you’ve probably had one. But how about an MRI? And why do some women need a PET scan or CT scan – and some don’t? The daunting array of cancer screening tests is less scary when you understand what each one entails, and what it might tell you.  

If you’re over 40, you’ve probably had at least one mammogram. The mammogram has been the breast cancer screening tool of choice for decades, and still is. Though far from perfect, it’s a relatively simple, quick, and inexpensive way to determine if a woman’s breasts are normal, or if they show evidence of disease.

Until recently, age 40 was the beginning of yearly mammograms for most women; two years ago, a U.S. Preventive Services Task Force report was released advising women to delay regular mammograms until age 50. The report said the number of women in their 40s benefiting by early detection of cancer via mammogram wasn’t enough to offset the number who suffered emotional stress and physical pain due to negative biopsies performed as a result of “suspicious” mammogram results.

As a result of enormous controversy surrounding these new guidelines, the USPSTF backed off its position somewhat, saying that women should consult with their doctors about the appropriate age to begin screening for breast cancer, based on personal risk factors.

Whether you have your first mammogram at age 40, age 50, or as a result of feeling a lump, you’ll know its results quickly – usually within a few days, or in some cases, within an hour or so. A radiologist will read the test (either on film, or digitally), and will let you know everything’s fine – or it’s not.

What happens when the radiologist sees something suspicious on that mammogram?

You continue down the diagnosis path. 

Ultrasound
An ultrasound is another simple, non-invasive test. Where a mammogram will detect a suspicious area – either something that’s changed from the year before, or something that doesn’t look like it belongs in the picture – an ultrasound can refine that view just enough to tell whether the area in question is solid, or liquid.

And what good does that do? If the suspicious area is solid, it requires more testing; if liquid, it’s assumed it’s a non-cancerous cyst, and your testing is over.

If the ultrasound rules out a cyst, then your doctor may request a biopsy, which will determine with almost complete accuracy whether the area is a cancerous tumor. Sometimes, however, it might be useful to get a clearer look at the area in question, before resorting to a biopsy. And MRI (magnetic resonance imaging) can provide that better look.
 
MRI
What does an MRI do? It uses a magnetic field, radio-frequency pulses, and a computer to produce a detailed image of your breast, from the inside out. Since the many images received show very thin “slices” of your breast, they can be put together and viewed from many different angles – unlike the images from an ultrasound or mammogram. An MRI gives a much more detailed image of the rather vague opaque area seen on a mammogram or ultrasound.