If you or your doctor feels a lump in your breast or an area of concern shows up on a mammogram, the next step may be breast ultrasound to help decide if the mass is cancer and whether it should be biopsied. Most lumps or areas of concern turn out to be benign (not cancer).
Two studies strongly suggest that breast ultrasound is very good at distinguishing between benign lumps and cancer in women younger than 40. So breast ultrasound may be able to help women younger than 40 avoid unnecessary biopsies.
In the first study, the researchers wanted to know if monitoring breast lumps with ultrasound was as accurate as doing a biopsy. So they looked at 1,091 lumps in 830 women younger than 30 with one or more ultrasounds. Based on the ultrasound results, the lumps were classified as benign, moderate-risk, or high-risk. The high-risk lumps were biopsied. All the women were followed for 2 years.
- All the lumps classified as benign were benign -- none were cancer. So ultrasound was 100% effective at classifying a lump as benign without a biopsy.
- The lumps classified as moderate-risk were monitored over time with more ultrasounds (this is called ultrasound surveillance). None of the lumps were cancer. One-third of the women with moderate-risk lumps had a biopsy -- even though it wasn't recommended -- usually because they wanted one. Still, all the biopsied lumps were benign.
- Only three of the high-risk lumps turned out to be cancer.
In the second study, 1,327 lumps in 1,032 women aged 30 to 39 were evaluated with an ultrasound and followed over time. Biopsies were done if the ultrasound suggested the lump could be cancer.
- The lumps classified as benign by ultrasound all proved to be benign over time. Like the first study, ultrasound was 100% effective at classifying a lump as benign without a biopsy.
- Most of the lumps classified as suspicious by ultrasound proved to be benign. Still, 25 women (2% of all women in the study) were diagnosed with breast cancer.
These studies strongly suggest that breast ultrasound is very good at distinguishing between benign lumps and cancer in women younger than 40. So lumps classified as benign or moderate risk likely can be carefully monitored without a biopsy. Other studies have shown that ultrasound can be effectively used the same way in women older than 40.
If you or your doctor finds a breast lump or a mammogram shows a mass or suspicious area, you'll understandably worry that you may have cancer. Be reassured that the odds are in your favor that the lump or mass isn't cancer. If you've found a breast lump, you may think an immediate biopsy to get an immediate answer is the best choice. Still, remember that a biopsy is an invasive procedure that should be done only when absolutely necessary.
Research suggests that ultrasound can be a very good alternative to immediate biopsy, allowing some women to avoid an unnecessary biopsy. If your doctor recommends a wait-and-watch approach with ultrasound surveillance but that approach doesn't feel right to you, talk to your doctor about your situation, your concerns, and your preferences. Together you can decide on a plan that makes the most sense for you.