Breakthrough in Breast Cancer Detection through CEM

Invasive lobular carcinoma, also referred to as lobular breast cancer, is a sort of breast cancer that starts initially in the milk-producing glands. This sort of breast cancer constitutes about 10% to 15% of all the breast cancers that happen and is said to be the second most common type of breast cancer, if not the topmost type of cancer found.

Also called lobules, from where the cancer starts, and then spreads to other surrounding areas. If the problem is quite old and has been left untreated for a long time due to any reason, it can spread to the nearby lymph nodes, which can then multiply in other areas of the body as well. However, if the symptoms are caught early and the treatment starts on time, this menacing disease of breast cancer can surely be cured.

Mostly, to diagnose this condition in women, the tests that are done are:

Mammogram: This test actually constitutes a low-dose x-ray that can detect any abnormalities in the breast tissue.

Ultrasound: This test is an imaging test that uses sound waves to capture images of the breast tissues. This test may or may not be used as a one-off test or can be suggested in combination with the mammography.

Magnetic Resonance Imaging (MRI): This sort of test takes the help of radio waves and magnets, which capture the images inside the body.

Biopsy: In this sort of test, a small specimen of breast tissue is taken and tested as such in the pathology laboratory for further analysis.  

The latest study published in the research international journal ‘Clinical Radiology’ on February 12 suggests that contrast-enhanced mammography (CEM) could be a good alternative to breast MRI for pinpointing lobular breast carcinomas. The research, led by Dr. Elisabetta Giannotti and her team in Cambridge, U.K., found that CEM is more sensitive than regular mammography, but both CEM and MRI tend to overestimate tumor size to a similar extent.

The team led by Giannotti wrote, “Traditionally, breast MRI has been used in many centers for preoperative staging, but CEM appears to be a suitable alternative”.

Contrast-enhanced mammography (CEM) is a sort of breast imaging technique that uses an iodine-based intravenous (IV) contrast agent in combination with a standard digital mammogram. There are some cancers that are not visible on standard mammograms. For those types, the addition of this iodine-based contrast makes it possible to get them detected. In a way, this type of iodine-based contrast agent is the same as used in normal CT scans but is somehow different from the gadolinium-based contrast agents, which are used in MRI.

The CEM can be used to examine the intensity of breast cancer in women, who are freshly diagnosed with breast cancer. It also can be used to keep a watch on the response of the chemotherapy being administered to the patient, before any surgery is performed. These help in addressing the breast symptoms or any abnormalities in the breast that are seen on the mammogram. The CEM can be recommended to patients who are not able to tolerate the MRI, even though it is recommended that they go through the MRI test.

The researchers noted that ultrasound and mammography often underestimate lesion size in lobular carcinoma cases, making detection challenging. This is because of the growth pattern and density of lobular carcinoma, which are similar to or less than those of normal fibroglandular tissue. Breast MRI is recommended for better detection in these cases.

Previous research has indicated that CEM performs similarly to breast MRI and could be beneficial for patients who can’t undergo an MRI. Dr. Giannotti’s team focused on evaluating CEM’s performance for invasive lobular carcinoma, comparing it to regular mammography and MRI.

The study included 115 lobular carcinoma cases, with 46 being symptomatic and 69 detected through screening. CEM showed a stronger correlation with histological size compared to regular mammography. Importantly, 19% of lobular carcinomas were not visible without a contrast agent.

CEM had a higher sensitivity (70%) for detecting multifocal disease compared to regular mammography (20%). However, CEM did not surpass regular mammography in terms of specificity (82% and 98%, respectively). Additionally, CEM tended to overestimate tumor size by an average of 1.5 times, similar to MRI.

The authors highlighted that their results align with previous studies on CEM for lobular carcinoma, considering them very encouraging. They stressed the importance of confirming and supporting these independent conclusions.