Prof Carol-Ann Benn introduces a series on the different types of breast cancer. The first cancer she tells us about is lobular breast cancer: the lazy psychopath.
The psychopath profile of a breast cancer
All cancers have the potential to kill; yet in all stories there is a hero. Every time I stop at a bookshop (a secret and scary passion of mine. I have books for Africa…three libraries full. Sorry trees!), I see another book on ‘Profiles of a psychopath’. So, I’m writing on the psycho profile of breast cancers. These are very tame psychos and most can be locked up, with a difficult get-out-of-jail option.
Mammograms and MRI scans
We have all heard stories of ‘I went for my mammogram and the cancer wasn’t seen on it’. So, let’s look more closely at when and why cancers can’t be seen clearly.
Mammograms today are digital, and can visualise small cancers a lot more easily. The use of tomography (a 3D-type mammogram) and the addition of breast ultrasound being performed at the time of a mammogram makes almost all cancers easier to detect.
Cancers can be difficult to detect in women with dense breast tissue. The reason why mammograms and ultrasounds should be done annually in specialised multi-disciplinary units is because subtle changes can be followed from year to year.
Remember, most breast cancers are slow-growing, and going for yearly mammograms is like wearing a seatbelt while driving. A seatbelt does not prevent an accident but rather protects us if we are in an accident.
MRI scans offer an additional way to assess the breast tissue in dense breasts. If a mammogram is looking from the side in a game-drive vehicle; an MRI is like looking from a helicopter. It is difficult to spot animals if the grass is long and there is lots of bush (dense breast). The helicopter can see from a different view but can also pick up shadows that may not be animals (cancer). The concern is that an MRI can over-read and result in unnecessary mastectomies.
Sleeping cancer – DCIS
By going for yearly mammograms, breast cancer can often be detected in its earliest phase (while it is still sleeping). This would be ductal carcinoma in situ (DCIS).
A sleeping cancer is still a cancer. It has just not woken up. The analogy is that of sleeping toddlers. While they’re sleeping, you can cook and work. And, if they are sleeping, they cannot get up to mischief.
But when a toddler is awake, he/she needs supervision. The more toddlers that are sleeping next to one another, the more chance there is of one waking another. Hence, the larger the area of DCIS, the more chance there is of small areas waking, and an invasive cancer being in the area.
Lazy lobular cancer
A cancer that is difficult to detect on a mammogram is lobular cancer. This is a type of breast cancer that has specific characteristics that makes it more difficult to see on a mammogram.
Lobular cancers account for about 10-15% of breast cancers, and occur more commonly in older women (those over 55). Some studies say that the use of hormone replacement therapy results in more lobular carcinomas, as there seems to be an increasing incidence in invasive lobular cancers. Though this data is not strong.
The look of lobular cancer
All cancers have different body shapes, and the clothes they wear give them certain personalities. This helps us understand their nature and how to treat them.
Lobular cancers look different to ductal cancers. The cells are small, round, bland, and they infiltrate (invade) in single file. So, lobular carcinomas are like ants walking along a wall (hard to see as they walk in single file). When ants surround a piece of food, they’re easier to see (this would be like ductal cancer).
These lazy lobular cancers don’t have E-Cadherin (which is glue in cancer talk). So, by not sticking together, lobular cancers do not destroy the anatomical structures or cause a response of surrounding tissue. Both of these features make cancers visible on a mammogram. So, because lobular cancers don’t cause these, they are harder to see on a mammogram.
Because of these features of spread, lobular cancers are more likely to be multifocal (found in more than one quadrant of the breast), multicentric (found in all quadrants of the breast), and, sometimes, mirror cancers can occur in the opposite breast (up to 20%).
The clothes lobular cancers wear are smart, natty dresses. Meaning they’re usually oestrogen and progesterone receptor-positive, and most are slow-growing, and are almost always HER-2 negative (marker for aggression). Basically, she is a well-dressed but mischievous psychopath.
Lobular cancer quirks
Because lobular cancer cells are small they can be missed when analysing the lymph nodes that breast cancers drain too. The cells in lymph nodes are small and lobular carcinoma cells are too. So, when pathologists looks at lymph node cells, down a microscope, they often use special stains to look for lobular cancer cells.
They usually present at a bigger size than ductal cancers because they are more difficult to see. Lobular cancer cells can present as an area of thickening in the breast; a swelling in the breast; dimpling of the skin; or pulling in of the nipple.
As with all cancers, the diagnosis should be made with a core needle biopsy as this gives the information about the cancer. Including the important E-Cadherin result, which should be negative.
An MRI is of value in assessing both breasts in women with lobular cancers.
What should you be told if diagnosed with lobular breast cancer?
Firstly, these cancers are slow-growing. Take time to listen to your breast specialist and ensure all the special stains (clothes) are available.
In our unit, an MRI scan is done prior to deciding what treatment is needed. If the radiologist can’t see any signs of cancer spread to the lymph nodes, the sentinel lymph node (the security guard gland) is assessed before any treatment is decided.
Just like when you have a sore throat and a gland in your neck becomes tender, so a woman who has breast cancer, a gland is switched on in the armpit. This is the sentinel lymph gland. This gland acts as a turnstile and any cancer cells that leaves the breast go via this gland.
Treatment pathway
Spread to the lymph nodes determines if radiation is needed. This information is pivotal in reconstructive options offered to patients.
Surgery and reconstruction
Surgery is suggested first in most lobular cancers. A possible exception being pleomorphic lobular cancers, and, obviously, when surgery is not possible due to size of the cancer.
Because of the chance of lobular cancers being in more than one area of the breast, and the difficulty of detecting it on a mammogram, a skin-sparing mastectomy and reconstruction is often the procedure selected by the patient and her treating doctor.
Note, many lobular cancers are unifocal so once an MRI scan is done, there is no reason not to do a local excision (breast conservation) in this setting (tumour is in one area).
There is 20% chance of a mirror cancer and so some women even elect to have a bilateral mastectomy and immediate reconstruction. Again, please understand that removing a breast that has no evidence of breast cancer is a psychological choice, not a scientific choice.
The most common type of reconstruction offered is usually a prosthetic reconstruction. However, the Goldilocks mastectomy (using tissue from below the breast) can be used; as well as many other options.
Chemotherapy and endocrine therapy
Because most lobular cancers are oestrogen and progesterone sensitive, they are usually less chemo sensitive and almost always require endocrine therapy. Usually tamoxifen for a minimum of five years. Though, more likely 10 years. Other endocrine therapies are also available.
Large lobular cancers can be shrunk down with chemotherapy if pleophormic, or sometimes endocrine therapy used first is a good option.
It is important that women diagnosed with lobular cancer are treated in a multi-disciplinary unit. This is because treatment decisions around surgery, reconstruction and the choice to use or not to use chemotherapy and radiation can be more complex.
So, welcome to the lazy psychopath of the breast cancer biology. Lobular cancer is hard to read; can beat a lie detector (radiology) due to shear failure to get a heart rate up as it sits and plans.
But, of course, it can be captured and put away for life. Just remember Sherlock Holmes needs Watson and the team to ensure this.
MEET OUR EXPERT – Prof Carol-Ann Benn
Prof Carol-Ann Benn heads up breast cancer centres at Helen Joseph Hospital and Netcare Milpark Hospital. She lectures at Wits University and, in 2002, established Breast Health Foundation.