What is breast cancer?

The most prevalent type of cancer in women is breast cancer. In fact, it's the second most leading cause of death from cancer in women; lung cancer is the first. In general, this cancer is formed by malignant breast cells, and it affects both women and men (less common). Also, it's a serious cancer due to its metastasis by the blood, bone marrow and the lymphatic system. As a matter of fact, breast cancer often forms calmly, so most patients learn about this cancer through regular screenings. Nevertheless, obvious changes in the breast, lumps or discharge from nipples indicates breast cancer. Besides, just like many cancers, the earlier the diagnosis, the more the survival rate.

Causes of breast cancer:

Normally, estrogen exposure can cause genetic mutations and DNA damage within the breast cells, so the immune system gets rid of these cells. This is not possible for patients with cancer, and it leads to a tumor.

The main cause of breast cancer is heredity. In other words, if your family has a history of this cancer, it's most probably that you carry the mutated genes responsible for the disease. Actually, 5-10 % of patients has this cancer due to genetic mutations. To illustrate, breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2) both hold respondibility for breast cancer.

However, carrying the risk factors or not doesn't always explain your likelihood of acquiring the cancer. That is to say, you may not have any risk factor but still get the disease, or you may have risk factors and never get the disease. Basically, it's the interaction between each person's genes and the environmental factors that triggers this type of cancer.

Breast cancer symptoms:

As has been noted, breast cancer is mostly asymptomatic during early stages. Therefore, it's accidentally caught on mammography regular screening. However, the more the cancer proceeds, the more common or rare sypmtoms show. The symptoms are:

• Breast pain in 5% of patients
• Lump that feels different and thick
• Thick pitted skin in the breast area (orange skin or peau d'orange)
• Frank ulcerations
• Inflammation (swelling and redness)
• Nipple discharge
• Inverted nipple
• Damage of the pigmented nipple surrounding area (areola)

Risk factors:

The risk factors of breast cancer are many, so it's important to keep on regular screening in order to detect it on early stages.

Gender: women are more likely to have this cancer, but some men can have it too.

Age: The older a woman get, the higher the risk for such cancer.

Family or personal history: Having a very close family member with the disease adds the risk 2 to 3 folds. Also, contralateral breast cancer is more likely if you had cancer in the other.

Genetic factors: carrying the genes BRCA1 and BRCA2 propose a high risk (10% of cases are due to genetic mutations).

Reproduction issues: whether it's giving birth at the age of 30, having menopause after the age of 55 or having menses before being 12 years old, they all add the risk.

Hormone usage: Taking progesterone or estrogen as supplements or for therapy are both risk factors. These include birth control pills known as "contraceptives" and hormone replacement therapy used by postmenopausal women.

Breast cancer diagnosis:

To diagnose this disease, a physical evaluation comes first, then there's imaging and biopsies.

• Screening mammography: it's possible to diagnose asymptomatoc breast cancer with this screening. Meanwhile, using mammography on young women isn't efficient.
• Ultrasonography: this allows evaluating the lumps size and stability.
• Magnetic resonance imaging (MRI): it has many uses such as:
  • Detecting abnormal breasts.
  • Finding occult lesions.
  • Indicating multifocal or bilateral malignancies.
  • Assessing the response to chemotherapy
  • Used with surgeries such breast conservation.
  • A screening tool for high risk patients.
• Tissue biopsy: It's vital to take a biopsy and observe it in details before diagnosing the cancer. Some tissue biopsy methods are core biopsy, fine-needle aspiration cytology, and incisional or excisional biopsy.

How to treat breast cancer:

The treatment relies on the stage of the cancer including the size. Mostly the treatment depends on surgery and it can be followed by radiation, chemotherapy or hormonal therapy (hormone blocking therapy). Indeed, chemotherapy focuses on destroying cancer cells (cells growing faster than the ordinary). In addition, radiation utilizes X-ray energy emitted externally through a machine, or uses radioative substances given internally. There's more treatments such as immunotherapy that makes it easier for the immune system to detect tumor cells, and targeted therapy drugs that targets specific pathways of the cancer cells to stop their growth.

Surgery:

Lumpectomy: it's also known as breast-conserving surgery. In fact, it might be enough to remove the tumor with some extra healthy tissues surrounding the tumor without removing the whole breast. Unlike big tumors, small ones doesn't require chemotherapy before the surgery. Ductal carcinoma in situ and stages I and II breast cancers need breast-conserving surgery and radiotherapy.

Mastectomy of one or both breasts: this is a surgery meant to remove the whole breast with all its tissues including the skin and nipples. However, it's possible lately to keep the breast in good shape by keeping the skin or the nipples. Moreover, some women choose to remove both breasts if there's a high risk of developing cancer in the contralateral breast. Stage III cancer requires induction chemotherapy followed by mastectony.

Sentinel node biopsy: Naturally, lymph drains into lymph nodes so it also drains from tumor tissues. Thus, it's important to remove the nearest lymph node and look for cancer. If no cancer is observed, then there's no cancer in the other lymph nodes.

Axillary lymph node removal: this occurs in case there's cancer in the sentinel lymph nodes.

References:

-Alkabban FM, Ferguson T. Breast Cancer. [Updated 2021 Aug 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482286/#_NBK482286_pubdet_

-Maughan KL, Lutterbie MA, Ham PS. Treatment of breast cancer. Am Fam Physician. 2010 Jun 1;81(11):1339-46. PMID: 20521754.

-McDonald ES, Clark AS, Tchou J, Zhang P, Freedman GM. Clinical Diagnosis and Management of Breast Cancer. J Nucl Med. 2016 Feb;57 Suppl 1:9S-16S. doi: 10.2967/jnumed.115.157834. PMID: 26834110.

-Mayo clinic "Breast cancer"

-Image credits: https://www.freepik.com/vectors/awareness-ribbon