What is Medullary Breast Carcinoma?
Medullary carcinoma is a rare type of breast cancer, making up less than 5% of all invasive breast cancers. This particular type of cancer has very specific criteria for diagnosis. The criteria include having at least 75% of the tumor displaying a certain pattern of growth, cells that are medium to high grade, a widespread presence of immune cells known as lymphocytes, and no presence of duct or gland-like features.
In 2012, the World Health Organization (WHO) updated its classification system and now refers to medullary carcinoma as part of a group termed “carcinomas with medullary features”. This group includes variations of medullary carcinoma and invasive carcinoma that show features similar to medullary carcinoma.
Despite the fact that medullary carcinoma may appear severe under the microscope and exhibits certain features normally associated with more aggressive cancers, it generally has a promising outcome when treated. This means that people diagnosed with this specific type of cancer have an encouraging chance of recovery.
What Causes Medullary Breast Carcinoma?
Studies have confirmed that a connection exists between certain types of breast cancer (medullary and invasive ductal carcinoma with medullary features) and changes in a specific gene known as BRCA1. In cases of breast cancer associated with this gene, between 7.8% and 19% are medullary carcinomas. Additionally, around 35% to 60% show characteristics related to medullary cancers. Contrastingly, only about 2% of medullary carcinomas occur in cancers not associated with the BRCA1 gene.
Medullary carcinoma has been shown to have specific gene expression patterns and features. It also often includes changes in the TP53 gene. In these cancers, cells often have an abnormal number of chromosomes, a condition called aneuploidy, and they frequently divide, known as a high S-phase fraction.
Peering closely at the genes in these cancers, researchers have found a consistent pattern of chromosome changes in medullary carcinoma. These changes include gains in certain chromosomes like 1q, 8q, 9p, 10p, and 16q, losses in chromosomes like 4p and X, and amplified segments in chromosomes like 1q, 8p, 10p, and 12p. These discoveries are crucial in understanding the genetics of breast cancer and help guide strategies for treatment and prevention.
Risk Factors and Frequency for Medullary Breast Carcinoma
Medullary carcinoma, a type of cancer, typically affects individuals at a younger age than invasive ductal carcinoma – usually within the range of 45 to 54 years. It typically centralizes in one location for most of the patients. However, there have been cases where the cancer spread to both sides, affecting between 3% to 18% of patients. This spreading, known as bilateral tumors, is more common in patients with a family history of the disease. Additionally, people having mutations in the BRCA-1 suppressor gene are seen to have a higher occurrence of typical medullary breast carcinoma.
- Medullary carcinoma usually presents in patients who are 45 to 54 years old.
- It typically affects a central location in most patients.
- 3% to 18% of patients have showcased two-sided (bilateral) tumors.
- Bilateral tumors are more common in people with a family history of the disease.
- Patients with mutations in the BRCA-1 gene are more prone to typical medullary breast carcinoma.
Signs and Symptoms of Medullary Breast Carcinoma
Medullary carcinoma typically shows up as a noticeable lump, generally in the upper outer section of the breast. The lump is often clearly visible during medical evaluations and screenings. Some people with this type of cancer may also have swollen lymph nodes in their armpits, an indication that the cancer might have spread to other parts of the body.
Testing for Medullary Breast Carcinoma
On a mammogram, medullary carcinoma (a type of breast cancer) often appears as a lump with rounded, oval, or irregular shape. The lump won’t have any calcium deposits and its edges will be well-defined. This can also be seen through ultrasound, where the lump would appear as a smooth and echoless mass.
An MRI test could also provide similar results, showing a round, oval, or irregularly-shaped mass with a smooth edge. The internal parts of the mass can look uniform or different and may show delayed accumulation of contrast agent (a substance injected in veins to make the structures visible in MRI). However, these features are not specific to medullary carcinoma and can also appear in other types of breast cancers and non-cancerous lumps.
Treatment Options for Medullary Breast Carcinoma
Treatment for the two types of medullary breast cancer, typical and atypical, is similar to that of a common type of cancer called invasive ductal carcinoma. It’s important to know that being classified as either typical or atypical doesn’t change the treatment choices for medullary cancer. Instead, these classifications are primarily used to help predict the outcome of the disease.
The usual treatment for medullary breast cancer includes surgery to remove the breast (called a mastectomy), which can be either modified or radical. This might also be combined with radiation treatment or chemotherapy, depending on how advanced the disease is. Medullary cancers are known to respond well to both radiation and chemotherapy.
If the tumor is 3 centimeters or smaller, it might be possible to undergo a breast-preserving surgery, followed by radiation therapy to kill any remaining cancer cells. Chemotherapy, a treatment that uses drugs to kill cancer cells, might be called for if the cancer is larger, has spread to the lymph nodes, or has invaded the blood vessels or lymph vessels.
What else can Medullary Breast Carcinoma be?
When a doctor is trying to diagnose medullary breast carcinoma, they essentially rule out other medical conditions having similar symptoms. These conditions include:
- Invasive carcinoma of no special type
- Chronic inflammation
- Lymphoma (cancer of the lymph nodes)
- Lymphoepithelioma-like carcinoma (a rare type of cancer)
- Melanoma (a type of skin cancer)
What to expect with Medullary Breast Carcinoma
Medullary breast cancer is a unique type of breast cancer that, despite having highly malignant or cancerous characteristics, generally has a more favorable outcome than the more common type of breast cancer known as infiltrating ductal breast cancer.Medullary breast cancer behaves differently from other types of breast cancer and standard prognosis factors do not apply as much.
The two most important factors affecting the prognosis of medullary breast cancer are the status of the lymph nodes and the size of the tumor. There is a belief that the large number of plasma cells and lymphocytes, which are types of white blood cells, in these cancers help to stop them from growing and spreading quickly.
The overall survival rate for patients with medullary breast cancer over a 10-year period is about 74%, and it even exceeds 90% in patients with no lymph node involvement.
Its vital to stick strictly to diagnosis criteria as pure medullary breast cancer has better outcomes than medullary cancer with unusual features. Studies have shown that both the involvement of lymph nodes and the size of the tumor, as well as distant spreading of the cancer, significantly lessen the overall survivability.
Possible Complications When Diagnosed with Medullary Breast Carcinoma
When we look at the research studies, we find that fewer patients with a rare type of breast cancer called medullary carcinoma have axillary lymph node involvement or cancer spread to the lymph nodes in the armpit (19% to 46%). This rate of lymph node involvement is lower when compared to more unusual types of medullary carcinoma (30% to 52%) or invasive ductal carcinoma (another type of breast cancer) where the chances go up to 29% to 65%.
What’s important to note is that medullary carcinoma patients with cancer in their lymph nodes have a lower survival rate over a 10-year period than those without any nodal disease (58.8% versus 97.1%).
Key Points:
- Medullary carcinoma patients have a 19% to 46% chance of cancer spreading to their lymph nodes.
- Atypical Medullary carcinoma and invasive ductal carcinoma patients have a higher 30% to 65% chance of cancer spread to the lymph nodes.
- Medullary carcinoma patients with cancer in the lymph nodes tend to live fewer years (58.8%) compared to those without lymph node involvement (97.1%).
Preventing Medullary Breast Carcinoma
It’s crucial that patients regularly check their breasts themselves. If they notice anything unusual, they should get in touch with their doctor right away. This way, if there is a problem, it can be caught and treated as soon as possible.
