What is Lobular Breast Carcinoma?
Invasive lobular carcinoma is the second most common type of breast cancer, making up 5% to 15% of all invasive breast cancers. This kind of cancer is made up of nonsticky cells that are either spread out individually or arranged in a straight line within a fibrous tissue area. Usually, it’s linked to another condition called lobular carcinoma in situ. Importantly, it’s different from the more common type of breast cancer known as invasive ductal carcinoma. Not only does it form differently at the molecular level, but it also impacts how it’s diagnosed and treated. Understanding these differences is essential for doctors to create the right treatment plan.
What Causes Lobular Breast Carcinoma?
Detailed scientific research has helped us understand the role of a protein called E-cadherin in the development of certain breast lumps or lesions. These studies suggest that conditions known as lobular carcinoma in situ and atypical lobular hyperplasia could play a part in the development of invasive cancer, rather than just being signals of the risk of developing such a disease.
The role of certain genes, for example, CDH1 mutations and PIK3CA, are considered crucial in the development of a type of breast cancer called lobular breast cancer. These genes are part of the phosphatidylinositol 3-kinase pathway, which is vital in the transmission of chemical signals within cells.
Risk Factors and Frequency for Lobular Breast Carcinoma
Breast cancer is a worldwide health issue. According to GLOBOCAN 2018, there are 46.3 cases per 100,000 people across the globe. However, in the United States, the rate is higher, with 84.9 cases per 100,000 people. Sadly, it’s also the second major cause of death from cancer, after lung cancer, with a death rate of 12.7 per 100,000 people.
A specific type of breast cancer, known as Lobular carcinoma, makes up 5% to 15% of all serious breast cancer cases. The average age of diagnosis is slightly older than another type, Invasive ductal carcinoma.
- Recent studies show that 45% to 51% of Lobular tumors are classified as ‘Luminal A’.
- These Luminal A tumors are less common in younger women (those 50 or under) and in Black women.
- They often show up as larger, low grade tumors
- Less frequently, they show flaws in the TP53 pathway.
- There is a trend for these tumors to be diagnosed in later stages.
Signs and Symptoms of Lobular Breast Carcinoma
Invasive lobular carcinoma is a type of breast cancer that often shows up as a lump or generally uneven tissue in the breast. It can also be discovered through routine mammogram screenings. Characteristics of this cancer are very similar to other types of invasive breast cancer.
It can be tricky to identify in the early stages because its growth is typically slow, and it tends to spread in a way that doesn’t show up well on mammograms. As a result, it often isn’t detected until it’s in an advanced stage.
When the cancer is advanced, patients may notice a visible lump in their breast, a slight thickening around the nipple, or a weepy scab on the skin. There might also be other changes in the skin like redness or swelling. The cancer can spread to lymph nodes in the armpit or near the collarbone. Therefore, it’s crucial for doctors to conduct a thorough examination to catch any significant signs.
A final important detail is that patients who have stomach symptoms and have had invasive lobular carcinoma in the past should routinely get upper digestive tract screenings. This is because this type of breast cancer can spread to the stomach.
Testing for Lobular Breast Carcinoma
Invasive lobular carcinomas are a type of breast cancer that can be difficult to detect and diagnose. These cancers often spread out in a branching pattern within the breast, making them hard to recognize during clinical examinations and imaging tests. As a result, these cancers are typically larger when they’re finally diagnosed. Furthermore, the cells of these tumors often look fairly normal under a microscope, making them easy to miss during biopsy procedures.
When it comes to mammography, or the use of X-rays to examine the breast, invasive lobular carcinomas can be more challenging to diagnose. They might present as an irregular mass, a change in the structure of the breast tissue, or a dense area in the breast. Small calcium deposits, also known as microcalcifications, which are common in other types of breast cancers, are less common in invasive lobular carcinomas. In some cases, mammograms might not show any changes at all despite the presence of cancer.
Using ultrasound, an imaging technique that uses sound waves to create a picture of the breast tissue, this cancer can present differently. It might appear as a mass that doesn’t reflect sound waves well (a ‘hypoechoic’ mass), an area that casts a shadow without a visible mass, a well-defined mass, or might not be visible at all.
One study found that using ultrasound in addition to the annual mammography can improve the detection of breast cancer in women who have been previously diagnosed with lobular neoplasia, a condition that can increase the risk of developing invasive lobular carcinomas.
Magnetic Resonance Imaging (MRI), a technique that uses a magnetic field and radio waves to create detailed images of body structures, can be helpful in estimating the true size of the cancer and its spread within the breast. This technique is often more effective than both ultrasound and mammography. MRI is particularly useful in detecting cancer in the opposite breast in older women with high risk for breast cancer.
On an MRI, an invasive lobular carcinoma often appears as an enhancing (or bright) solitary nodule with irregular or spiky edges. In the case of classic invasive lobular carcinomas, where the cancer cells spread along the natural divisions within the breast (septa), the MRI might show these septa as brighter areas without a primary tumor focus.
Treatment Options for Lobular Breast Carcinoma
The approach to treating invasive lobular carcinomas, a type of breast cancer, has been a topic of discussion due to the potential for the cancer to affect both breasts and multiple locations within the breast. Determining how extensive the cancer is becomes crucial in deciding the appropriate treatment. This cancer type is relatively slow-growing, which means there is usually ample time for various types of treatment.
Treatment involves a team approach and often includes surgery, hormonal therapy, radiation therapy, and chemotherapy. Sometimes prophylactic contralateral mastectomy, or precautionary removal of the opposite breast, is performed as a preventive measure.
One of the standard treatments for invasive lobular carcinomas is either mastectomy (removal of the entire breast) or lumpectomy (removal of only the cancerous lump). If before surgery, examinations indicate that the cancer hasn’t spread extensively, conservative treatment is usually deemed suitable. In these cases, surgeons don’t need to ensure extensive cancer-free margins (additional tissue around the tumor that’s removed to ensure all the cancer cells are gone) after the surgery.
Surgery and radiation therapy work together to control the spread of the cancer in the surrounding regions. The lack of fibrotic reaction (the process of forming scar-like tissue) in these cases makes it challenging for doctors to estimate the size of the cancer during surgery and ensure all cancer cells have been removed.
As with other cancers, the way the medical team proceeds in treating invasive lobular carcinomas depends on the cancer’s stage at that point. If the cancer is operable, surgery might go ahead, or the patient may undergo preoperative therapy before surgery depending on the specific case.
Typically, treatment for early-stage invasive lobular carcinoma could involve surgical excision followed by radiation therapy, similar to invasive ductal carcinoma (another type of breast cancer).
Adjuvant hormonal therapy, which is additional treatment given after the primary treatment, is recommended due to the high percentage of these cases being positive for ER and PR (types of hormone receptor proteins that can promote the growth of breast cancer cells when they latch onto hormones).
Chemotherapy seems to have limited benefit for these patients due to the cancer’s low proliferation (growth) rates.
However, treatment decisions don’t depend solely on the cancer’s microscopic appearance (histology). Other factors, like the patient’s age, lymph node status, size of the tumor, presence of the Ki-67 biomarker (a protein associated with cell proliferation), and the hormonal status are also taken into account when predicting chances of recurrence and survival rates.
What else can Lobular Breast Carcinoma be?
When attempting to identify invasive lobular carcinoma, a type of breast cancer, doctors may also consider the following conditions that might look similar:
- Invasive ductal carcinoma with lobular features
- Gastric signet ring carcinoma metastatic to the breast
- Sclerosing epithelioid fibrosarcoma
- Leukemic and lymphomatous involvement of the breast
- Rosai-Dorfman disease
- Granular cell tumor
These could be potential findings and each one would require a different treatment strategy. Therefore, it’s crucial for the doctor to differentiate between these conditions for the most optimal patient care.
Surgical Treatment of Lobular Breast Carcinoma
Breast-conserving surgery (which is a surgery where only part of the breast tissue is removed) with radiotherapy (a treatment that uses high-energy radiations to kill cancer cells), or mastectomy (a surgical procedure to remove all breast tissue), is a suitable treatment option for invasive lobular carcinomas (a type of breast cancer beginning in the milk-producing glands (lobules)) based on the location and size of cancer and patient preference. This is similar to the treatment options for other invasive breast cancers.
Studies have shown that the survival rate and local recurrence rates (the return of cancer in the same place as the original tumor) for patients with invasive lobular cancer are similar to patients with ductal/no special type carcinoma (breast cancer starting in the cells lining the ducts) at 5 years, if managed by breast-conserving surgery.
However, it is seen that late recurrences (cancer coming back after treatment) can happen in patients after 10 years. Also, conversion from breast-conserving surgery to mastectomy is often required in patients treated for invasive lobular carcinoma due to positive margins (cancer cells are seen at the edge of the tissue removed during surgery), especially for those treated with neoadjuvant chemotherapy (a treatment to shrink a tumor before the main treatment, usually surgery).
Research suggests that almost 50% of people with invasive lobular carcinoma who were treated with neoadjuvant therapy needed a full mastectomy due to incomplete removal of cancer. There is also evidence suggesting that this type of breast cancer may resist neoadjuvant chemotherapy more than invasive carcinoma of the ductal, or no special type. On the other hand, it has been observed that patients with invasive lobular carcinoma benefit more from endocrine therapy (a treatment that adds, blocks, or removes hormones to slow or stop the growth of cancer cells) with a greater increase in survival compared to those with ductal or no special type breast cancers.
What to expect with Lobular Breast Carcinoma
Research has found that invasive lobular carcinoma, a type of breast cancer, may have the same, better, or worse outcomes than invasive ductal carcinoma, another kind of breast cancer. This depends on factors like the timing of check-ups and the number of patients in the study. This is because lobular carcinoma is known to have fewer early reappearances and shows less involvement of the armpit’s lymph nodes at the time of diagnosis.
Lobular carcinoma often spreads to the ovary, digestive tract, uterus, lining of the body’s cavities, the membranes surrounding the brain and spinal cord (meninges), or bone rather than local lymph nodes or lungs.
Advanced age (over 60 years), larger tumor size, and the spread of cancer to the lymph nodes in the armpit are believed to result in poorer outcomes.
Some studies have reported that pleomorphic, a variant of lobular carcinoma, is a particularly aggressive form of cancer with a high chance of recurring and causing death from the disease.
Possible Complications When Diagnosed with Lobular Breast Carcinoma
Invasive lobular carcinoma, a type of breast cancer, has been reported to have a slightly lower rate of spreading to the lymph nodes in the armpit, compared to another type known as invasive carcinoma of no special type. The rate of this spread, or metastasis, varies with a difference of 3% to 10% according to some studies.
Another difference between these two types of breast cancer is where they are likely to spread beyond the breast. Invasive lobular carcinoma tends to spread more often to areas such as the bone, gastrointestinal tract (stomach and intestines), uterus, lining of the brain and spinal cord (meninges), ovaries, and the lining of body cavities (serosa). Meanwhile, breast cancer of no special type more commonly spreads to the lungs.
Common Places of Metastasis:
- Armpit lymph nodes
- Bone
- Gastrointestinal tract (stomach and intestines)
- Uterus
- Meninges (lining of the brain and spinal cord)
- Ovaries
- Serosa (lining of body cavities)
- Lungs
Recovery from Lobular Breast Carcinoma
After breast cancer surgery, patients will need to know how to manage their wounds. During surgery, the doctors usually use special stitches that dissolve on their own, so there’s no need to have them removed. We usually advise patients to take a shower two days after their surgery, whether they’ve had a full or partial mastectomy. During the operation, a flexible tube, called a drain, is placed under the skin to collect and remove any fluid that builds up at the surgery site. This drain is usually removed one to two weeks after the operation during a clinic visit, once the drainage has lessened.
If patients experience any of the following symptoms, they should contact their doctor immediately:
* Fever (38 degrees C or higher)
* Swelling or redness around the surgical area
* Fluid leaking from the wound or the area around the drain
* The wound starts to break down
* Increased pain at the surgical site
After surgery, patients usually continue taking the medications that their doctor prescribed. There may also be certain foods that they should avoid.
It’s important to try and return to normal activities as quickly as comfortably possible following surgery. Most patients who’ve had a full or partial mastectomy can return to their daily routines immediately after surgery. However, those who’ve had breast reconstruction surgery will need to take certain precautions.
Exercising the arm can help to promote a healthy lymphatic system and good circulation, which can prevent swelling in the arm. It’s a good idea to avoid strenuous activities for a few weeks after being discharged from the hospital.
After surgery to the armpit (axillary surgery), there’s an increased risk of arm swelling (lymphedema) and infection. Because of this, it’s important to take extra care to protect the arm and hand that are on the same side as the surgery. Some patients may be referred to a physical or occupational therapist who’s been specially trained in how to treat lymphedema.
For those who’ve had a mastectomy, physical appearance can be preserved through breast reconstruction surgery or by wearing a prosthesis.
Preventing Lobular Breast Carcinoma
It’s crucial for patients to get into the habit of regularly checking their own breasts and immediately seeking medical advice if they notice anything unusual.
Doctors and the whole healthcare team should make sure that patients are thoroughly informed about invasive lobular carcinoma, a type of breast cancer. It can be beneficial to direct patients to educational websites and give them written materials—a sort of guide—to help them understand their condition. It’s important to provide patients with enough knowledge about their illness, what they can likely expect in the future (prognosis), and the various treatment options available to them.