What Are the Causes and Risk Factors of Breast Cancer?

The causes of breast cancer fundamentally stem from a complex interplay of genetic predisposition, prolonged hormonal exposure, and environmental factors. In this disease, which begins with the uncontrolled multiplication of cells, BRCA1 and BRCA2 gene mutations, obesity, advanced age, and alcohol consumption rank among the most well-known risk factors. In this guide, prepared in accordance with medical E-E-A-T standards and thoroughly reviewed by our specialist physicians, we explore the factors that lead to breast cancer and the ways to protect yourself in full detail.

• Between 5% and 15% of breast cancer cases are genetically inherited.
• Advanced age and female gender are the most fundamental, unchangeable risk factors.
• Starting menstruation early and entering menopause late increases estrogen exposure, thereby elevating the risk.
• Obesity and a sedentary lifestyle pose a serious risk, particularly in the post-menopausal period.
• Early detection saves lives; regular screenings must never be neglected.

What is Breast Cancer and Who Gets It?

Breast cancer is a condition where the DNA structures of the cells making up the breast tissue become damaged, leading them to multiply uncontrollably and form a tumour. It frequently begins in the milk ducts (ductal carcinoma) or the milk glands (lobular carcinoma). Over time, these growing cells carry the potential to spread to the lymph nodes or other organs in the body.

So, who gets breast cancer? Ranking second among the cancer types seen in women, this disease carries a lifetime risk of affecting one in every 7 to 8 women. While it can also be seen in men, it is much rarer compared to women. Advanced age is one of the most significant factors increasing the incidence of the disease. Although it is generally diagnosed more frequently in women aged 50 and over, it can emerge even in their 30s in individuals with a genetic predisposition.

Causes and Risk Factors of Breast Cancer

It is difficult to speak of a single cause for the emergence of the disease. Unchangeable risk factors that are not dependent on the individual account for 30-40% of cases. Environmental factors, shaped by exposure to carcinogenic substances brought about by industrialisation and poor dietary habits, are seen to have a high rate of 60-70%.

Genetic and Hereditary Factors (BRCA1 and BRCA2)

The first question on many patients' minds is whether breast cancer is genetic. Among all cases, the number of patients associated with genetic inheritance is between 5% and 15%. Mutations in the BRCA-1 and BRCA-2 genes, in particular, significantly increase the risk of breast and ovarian cancer. It is of great importance for individuals who have a history of breast cancer at a young age in their family, especially in first-degree relatives (mother, sister, aunt), to receive genetic counselling.

Hormonal Causes (Estrogen Exposure)

Breast tissue is highly sensitive to estrogen and progesterone hormones. The longer one is exposed to these hormones throughout life, the stronger the factors leading to breast cancer become. Having a low age at first menstruation (before age 12) and entering menopause at an advanced age (after age 55) causes the body to be exposed to the estrogen hormone for a prolonged period. Similarly, never having given birth or having the first birth after the age of 30 are also considered hormonal risk factors.

Environmental Factors, Obesity, and Lifestyle

Diet and nutritional habits are the most important among modifiable factors. Dietary factors are accepted to have a 30-35% reducing effect on breast cancer risk. Adopting a Mediterranean-style diet—rich in olive oil and the fresh, seasonal greens you can easily find at any local Turkish market—can be highly beneficial. In obese patients, the risk of breast cancer is closely related to menopausal status. While a high body mass index in the pre-menopausal period does not create a very significant change, obesity becomes a serious risk factor in the post-menopausal period. The risk in post-menopausal obese women increases by 25% compared to women of normal weight. Furthermore, it is reported that obesity increases the recurrence rate of the disease by 30-40%.

Metabolic syndrome, low HDL cholesterol, high blood sugar, and insulin resistance can also trigger the canceration process at the cellular level. There is a direct proportion between alcohol consumption and the disease; the risk increases in those who consume high levels of alcohol. You can review detailed information on this topic in our article Breast Cancer Risk Factors: Is It Genetic or Preventable?

What Are the Symptoms of Breast Cancer?

The disease is usually painless in its initial stages and may not cause any complaints. However, as the tumour grows, certain physical symptoms appear. The most common symptom is palpable, usually painless, and hard-structured lumps within the breast tissue or under the armpit. These lumps tend to have irregular borders and be immobile.

In addition to this, thickening of the breast skin, a peau d'orange (orange peel) appearance, redness, or flaking are signs that must be taken seriously. The inward retraction of the nipple, a change in its shape, or a bloody discharge from the nipple can be a herald of an advanced problem. When a noticeable asymmetry or deformity that appears later between the two breasts is noticed, a specialist should be consulted without wasting time.

Diagnosis and Detection Process at the Hospital

The gold standard in diagnosing breast cancer is regular screenings and radiological imaging methods. Although breast self-examination is important for raising awareness, the definitive diagnosis is made in a hospital setting. It is recommended that every woman from the age of 40 have a mammogram once a year. Mammography can detect tumours when they are still millimetric in size, long before they can be felt.

When necessary, breast ultrasonography and breast MRI (Magnetic Resonance) are also included in the process. When a suspicious lump is detected by imaging methods, a biopsy is performed for a definitive diagnosis. The tissue sample taken by fine or core needle biopsy is examined in the pathology laboratory to determine whether the cells are cancerous and, if so, what type they are. For more information about screening processes, you can browse our content titled Age-Based Breast Cancer Screening Calendar and Examination Guide.

Breast Cancer Treatment Methods

Treatment planning is determined on an individual basis with a multidisciplinary approach according to the patient's age, general health status, the stage of the tumour, hormone receptor status, and genetic makeup. The surgical leg of the treatment is carried out by our hospital's General Surgery department. While breast-conserving surgery, where only the tumour and a small amount of surrounding healthy tissue are removed, is preferred in early stages, removal of the entire breast (mastectomy) may be necessary in more advanced cases.

Following surgical intervention, or sometimes before surgery to shrink the tumour, chemotherapy, smart drug therapies (targeted therapies), or hormonotherapy are applied by the Medical Oncology unit. In addition, radiotherapy (radiation therapy) is frequently added to the treatment protocol to destroy any microscopic cancer cells that may be left behind.

Complications and Risk Groups

When breast cancer is not treated or when intervention is delayed, it carries the risk of metastasising (spreading) to vital organs such as the bones, liver, lungs, and brain via the lymph nodes. Furthermore, there is a possibility of the disease recurring in the same breast or the other breast during the post-treatment period. For this reason, it is essential for patients whose treatment has been completed to continue regular follow-ups for life, more frequently in the first few years.

Those who carry a BRCA mutation in their family, those who have previously received radiotherapy to the chest area, those who struggle with obesity, and heavy alcohol consumers are in the high-risk group. It is recommended by physicians that these individuals start screening programmes at an earlier age than normal and undergo more comprehensive tests.

When to See a Doctor?

When you notice an unusual situation regarding your breast health, the best approach is not to wait. In cases such as a newly formed hard lump in the breast, bloody or clear discharge from the nipple, sudden redness on the skin, and an orange peel appearance, you should immediately see a general surgery specialist.

However, symptoms such as sudden severe pain in the breast, excessive swelling, intense redness, and accompanying high fever may indicate an infection (mastitis) or rapidly progressing inflammatory breast cancer. In such sudden and severe clinical pictures, it is of vital importance to apply to our hospital's Emergency Medicine department or call 112 without losing time.

The Process at BHT CLINIC İstanbul Tema Hastanesi

At BHT CLINIC İstanbul Tema Hastanesi, all diagnosis and treatment processes related to breast health are meticulously carried out by councils consisting of specialist physicians in their fields. Our General Surgery, Medical Oncology, Radiology, and Pathology departments work in complete harmony to offer our patients the most up-to-date and scientific treatment options.

With our advanced technological infrastructure, patient-oriented approach, and our Emergency Medicine unit providing uninterrupted service 24/7, we are by your side at every moment of your health. To benefit from the life-saving power of early diagnosis and to have your routine check-ups, you can easily book an appointment through our call centre or our website.

Frequently Asked Questions

Below you can find the answers to the questions our patients are most curious about regarding breast cancer causes and risks.

Does stress cause breast cancer?

There is no definitive scientific data proving that stress directly causes breast cancer. However, chronic stress can indirectly increase the risk of cancer by weakening the immune system and leading the person to unhealthy habits such as poor nutrition, alcohol, or smoking.

Do birth control pills increase the risk of breast cancer?

Some studies have shown that long-term and uninterrupted use of birth control pills may very slightly increase the risk of breast cancer. However, within 10 years after stopping the medication, this risk decreases and returns to normal levels. The decision to use the medication should be made together with a physician, considering the risk-benefit balance.

Can men get breast cancer?

Yes, because men also have breast tissue, breast cancer can develop. Approximately 1% of all breast cancer cases are seen in men. Men who have a BRCA mutation in their family or who have liver diseases causing intense estrogen exposure are particularly at risk.

Does sugar consumption trigger breast cancer?

Although there is a common belief that sugar directly feeds cancer cells, the real danger is that sugar leads to obesity and insulin resistance. Obesity and metabolic syndrome are proven factors that significantly increase the risk of breast cancer, especially in the post-menopausal period.

Can breast cancer be completely cured?

The rate of complete recovery (cure) in breast cancer diagnosed at an early stage is quite high. Thanks to modern surgical methods and advanced oncological treatments, the vast majority of patients can completely overcome the disease and lead a healthy, long life.

This article is for informational purposes only; please be sure to consult your doctor for diagnosis and treatment.