By Sophie He
Introduction
Breast cancer is the most common form of cancer to affect women. According to the Centers for Disease Control and Prevention, about one in eight women gets breast cancer in her lifetime (CDC, 2021). This number is high because no other forms of cancer affect women at this rate. For comparison, the second most common form of cancer is lung cancer, and one in 17 women gets it. Most forms of breast cancer test positive for either estrogen or progesterone. However, triple negative breast cancer (TNBC), one of the most challenging forms of cancer to treat, tests negative on estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2). Because there are fewer receptors in TNBC, there are fewer treatments available. TNBC has a high recurrence rate and may spread even faster than other forms of breast cancer.
Demographics
Source: Plasilova et al., (2016).
Compared to men, women are twice as likely to contract TNBC. TNBC is present in Non-Hispanic black and Hispanic more than other ethnic/racial groups. Most people with TNBC are young and under the age of 40. America is separated into nine regions and the East South Central has the highest percentage of people with TNBC in all regions of the United States. Around 15.8% of people with TNBC are from the East South Central group. People who use hormonal birth control and those who have not breastfed previously represent risk factors. However, Filipino women have the lowest likelihood of getting TNBC (Plasilova et al., 2016).
Symptoms and Tumor Size
Source: Plasilova et al., (2016).
The common symptoms of TNBC are very similar to other forms of breast cancer. For example, those who suspect they have breast cancer may experience a lump in the breast or fluid leaking from the breasts. At this point, they should get a mammogram, ultrasound, or biopsy to determine whether or not they have TNBC (Triple-Negative Breast Cancer, 2022). The image below is a comparison of TNBC and a receptor-positive tumor). The most common tumor size for people with TNBC was 2–5 cm. The most common grade for people with TNBC is Grade 1 and 2 meaning only very few cells are abnormal. However, Grade 3 cancer is also possible and it means that the cancer is spreading fast.
Source: Gallego (2012).
Survival Rate and Recurrence Rate
After getting the proper treatment, the survival rate for TNBC in just the breast is 91%. However, if the person with TNBC has regional TNBC, meaning the breast cancer has spread to nearby areas, then the survival rate is 65%. And if the person has distant TNBC, meaning the cancer has traveled away from the breasts to nearby organs, then the survival rate for the patient is only 11%. This distant TNBC is also known as metastatic cancer. Compared to other breast cancers, TNBC has a high recurrence rate. It is the highest during the first three years. However, if the person with TNBC continues with radiation therapy, the recurrence rate can be lowered to 3% by the 10th year after diagnosis ( BCRF, 2022).
Therapy
Source: Plasilova et al., (2016).
Treatment varies from case to case, but the main treatment options for TNBC are lumpectomy, mastectomy, radiation, and chemotherapy. The treatment depends on the person with TNBC’s health, stage, grade, and location of cancer. Generally before the surgery, the person with TNBC gets chemotherapy, specifically neoadjuvant chemotherapy. The person has two options for surgery: lumpectomy and mastectomy. Lumpectomy is only removing part of the breast, while mastectomy is removing the whole breast. After surgery, the person with TNBC has to undergo chemotherapy again to reduce the risk of cancer returning (BCRF,2022). During the second round of chemotherapy, this time adjuvant chemotherapy, a common drug that is used is called anthracycline (Cancer Research, 2020).
References
BCRF I (2022, March 9). Triple-Negative Breast Cancer: Symptoms, Treatment, Research. Breast Cancer Research Foundation https://www.bcrf.org/blog/triple-negative-breast-cancer-treatment-symptoms-research/
Cancer Prevention and Control (2021, September 20). “Triple-Negative Breast Cancer.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention., 20 Sept. 2021, https://www.cdc.gov/cancer/breast/triple-negative.htm#:~:text=What%20Is%20Triple%2DNegative%20Breast,for%20the%20female%20hormone%20estrogen.
Cancer Research (2020, April 3). “Triple Negative Breast Cancer.” Triple Negative Breast Cancer. | Cancer Research UK., 3 Apr. 2020, https://www.cancerresearchuk.org/about-cancer/breast-cancer/stages-types-grades/types/triple-negative-breast-cancer.
Eldridge, L (2021, December 17. Triple-Negative Breast Cancer Prognosis. Verywell Health. https://www.verywellhealth.com/triple-negative-breast-cancer-prognosis-4778440
Gallego, P (2022, March 1). Triple Negative and Me: TNBC and Its Treatments. OWise UK.https://owise.uk/tnbc-triple-negative/
Plasilova, M, Hayse, B, Killelea, B, Horowitz, N, Chagpar, A, and Lannin, D (2016, August). Features of Triple-Negative Breast Cancer. Medicine. https://journals.lww.com/md-journal/fulltext/2016/08300/features_of_triple_negative_breast_cancer_.38.aspx
Triple-Negative Breast Cancer (2022, March 1). Triple-Negative Breast Cancer: Details, Diagnosis, and Signs. American Cancer Society. https://www.cancer.org/cancer/breast-cancer/about/types-of-breast-cancer/triple-negative.html