Introduction
Breast cancer is the most common cancer in the world for women, and second to lung cancer for causes of cancer deaths in women. In 2017 alone, 252,710 new diagnoses of breast cancer are expected from women, and approximately 40,610 are likely to die from this disease. Breast cancer can also affect men, although women are at a much higher risk of getting it. Breast cancer is a type of cancer that is found in the breast, armpits or upper chest. Each breast contains 15-20 glands called lobes, where milk is produced. They are connected to the nipple by tubes called ducts, and together they resemble the structure of branches on a tree. These lobes run through the breast to the armpit. Most of the rest of the breast is fatty tissue. Usually, breast cancer begins in the lobes. The breast and armpit also have lymph nodes and vessels that carry lymph liquid, which are a part of the immune system. Breast cancers can spread/metastasize to the rest of the body through the lymph system or blood vessels. Breast cancer that starts in the lobes are called lobular carcinoma, while the more common one, ductal carcinoma, begins in the milk duct.
How do cancers start
Our body is made up of a countless number of cells, and these cells can be different due to their primary job in the body, as skin cells wont be the same genetically as brain cells. Each cell contains DNA, which differentiates the cells. Over time, our body replaces the old cells through mitosis, where the existing cell makes an extra copy if it’s DNA and splits into two, so both new cells have a complete set of identical DNA. This process happens millions of times throughout our lifetimes. When the cell splits, there are normally a number of checks to make sure the DNA was copied correctly and there are no mistakes in it, which would hinder how the cell would function, and if there is a mistake, the cell dies. However, these safety checks can fail, allowing the cell to survive despite having an incorrect DNA copy. This is known as a mutation, and normally they are of no harm, although the new DNA could make the cells behave strangely, splitting into identical cells at a rapid rate, forming a tumour. If the tumour cells don’t have the uncommon ability to grow into neighbouring tissue, they are called benign tumours, and usually don’t need treatment and are not cancerous. On the other hand, if they can invade neighbouring tissue, they are cancerous, and should be treated immediately; otherwise they will grow and spread, which is life threatening. Breast cancer can grow if untreated, taking the surrounding tissue in the breast. Primary breast cancer is where the cancer hasn’t spread beyond the breast or armpit, although it can break away from the original cancer and enter the lymph nodes and blood vessels, allowing it to travel through them and settle in another part of the breast tissue, forming new tumours. Cancer cells can also spread to other areas in the body and form new tumours, which are called secondary breast cancers.
Background knowledge
Symptoms to breast cancer may include a lump or thickening in or around the breast or underarm area, change in size or shape of the breast, dimple or puckering in the skin of the breast, a nipple turned inward, fluid such as blood exiting from the nipple and scaly or swollen skin on the breast or nipple.
There are many ways to test for breast cancer. The simple way, is a physical and to use history of the patient. They examine the body for signs of disease, such as the lumps or any other unusual feature, while a history of the patient’s health habits and past illnesses and treatments will also be looked at. A clinical breast exam, where a professional thoroughly examines the breasts and underarms can be done. A mammogram is an x-ray, where the breast is pressed between two plates and it is used to take pictures of breast tissue. An ultrasound, which is a procedure where high-energy sound waves are bounced off internal tissues to make echoes that form a picture of body tissues called a sonogram, can be also used. A procedure that uses radio waves, a magnet and a computer to take detailed pictures of both breasts called an MRI (magnetic resonance imaging) is also used.
For breast cancer, there are three common treatments that are regularly used. Most patients remove breast cancer using surgery. Breast-conserving surgery is where the surgeon removes the cancer and normal tissue around it, but leaves the breast. Total mastectomy, otherwise called simple mastectomy, is another surgery where they remove the whole breast that has cancer. They may also remove some of the lymph nodes under the arm and check them for cancer. Chemotherapy may be given before surgery to remove the surgery. It shrinks the tumour and reduces the amount of tissue that needs to be removed. They use drugs to stop growth of cancer cells by killing or stopping their growth. It does have drawbacks, depending on the drugs used; chemotherapy could have late side effects such as heart failure, blood clots or development of a second cancer, such as leukaemia. Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer. External radiation therapy is where machines are you to send radiation to the cancer, while internal radiation therapy uses needles or wires to place radioactive substances close the cancer. However, radiation therapy can cause the other breast to develop cancer, or lung inflammation.
Method
The method that was used to acquire the data was by formally sending a letter to a local hospital for information to aid my research. Luckily, they accepted my proposal and were able to supply sufficient and relevant raw data. With the data acquired, I will be able to research my topic and conduct an analysis and suggest a reliable conclusion.
Hypothesis and Null Hypothesis
My hypothesis is that both age and weight increase the risk of breast cancer in females. My null hypothesis is that there will be no correlation between age and weight increasing risk of breast cancer.
Risk factor – Age
Research
Age is the one of the biggest risk factors for cancer. Breast cancer increases significantly after the age of 50. There are many theories to this; one of them is that they develop due to the extended exposure to carcinogens such as radiation, sunlight, environmental chemicals and substances in the food we eat. Mutations that can cause cancerous cells to occur due to random errors when a cell’s DNA is being copied before it divides, and our cells mutate more the longer we live, giving more chances for cancerous cells to manifest. Changes in tissue and organs with increasing age allow the cell microenvironments to favour the development of cancer. Other factors that can manifest due to age include the long-term effects of chronic inflammation, which causes DNA damage in cells because of oxygen free radicals, less effective repair mechanisms for DNA damage and a continuous weakening of the immune system that makes it less effective in spotting and attacking cancer cells. Menopause is also linked to cancer and age, because some women choose to take hormonal pills to negate the effects of menopause, as there are many physical problems that come with menopause, and these hormones such as oestrogen increase risk of developing cancers. The more ovulations a woman have in her life, the higher the risk to breast cancer and other cancers such as uterine and ovarian cancers. This is because there is higher exposure to hormones such as oestrogen. Some breast cancer cells need oestrogen to grow, because some of then bind to proteins called hormone receptors, which grow when hormones are received. Epidemiological studies have also firmly established a correlation between risk of breast cancer and other reproductive factors, such as having no children, late age at first birth, and breast-feeding. There is also thought to be a short-term increase of risk of developing breast cancer, lasting up to five years after giving birth, although having at least one child is linked to a decrease in long-term risk of breast cancer, and is better than having no children (nulliparous), and this long-term protection increases with the number of children, each birth decreases the corresponding risk by an average 7%, and another observation is that the reduction in risk per birth of breast cancer is larger for births at younger ages, as women who have their first birth around 20 years of age have a 30% lower risk than women with a first born after the age of 35. Oestrogen has been proposed to explain both the increase and decrease in risk of breast cancer associated with pregnancy and age. The high levels of oestrogen and progesterone during pregnancy stimulate growth of mammary epithelium and also promote the differentiation of epithelial tissue, reducing the number of epithelial structures most vulnerable to malignant transformations. However, the short-term effect could be to promote growth of cancer if a malignant transformation is present in the breast, but the risk is reduced in the longer term. On the other hand, malignant transformations are more probable to have increased in number in the breast tissue of older women, which is why there might be an increase in risk of breast cancer manifesting in older women when the cells are stimulated to divide during pregnancy. Thus, the effect of age at first birth shows the importance of timing of exposure as a serious determinant of the effects of steroid hormones such as oestrogen (Travis, Key 2003).
To decrease risk in getting breast cancer due to age, you must increase physical activity, spend more time sleeping and less time sitting around and not moving, eat a more balanced and healthy diet, moderate alcohol use and quit smoking.
Analysis
Data Graph 1.0: This is a table that shows all the cancer patients and their ages. It shows how many patients there are in each age group.
This graph shows that out of 113 patients of breast cancer in Jeddah, Saudi Arabia, the age group that were most prevalent was between 50 and 59, where there were 31 patients. It shows that there were 29 people diagnosed at ages between 20 and 29, and 24 diagnosed between 60 and 69. It confirms the fact that age is a risk factor, because there are more people being diagnosed with breast cancer after the age of 50 than before. Only 15 people were diagnosed between the ages of 20 and 39, which shows how there is much less people being diagnosed with breast cancer at younger ages. Menopause normally occurs around the age of 50, depending on when people began their menstruation cycle and their genetics, so this confirms the fact that hormones such as oestrogen do increase the risk of breast cancer. Another indicator of this is that the mean of the data is 53.6; showing how prime age of menopause and beginning of old age is when breast cancer manifests. A reason why much older people ages 80-89 aren’t as high could be due to less people at that age noticing or reporting new symptoms to their doctors and caretakers. The median is also 53, which means that the middle age of all the patients is 53, and it is almost exactly the same as the mean of the age, which indicates evenly distributed data, which is good for validity and diversity. The range is 65, which is a very wide range that means there is a big difference in ages. The mode for the data is 47, which appeared 6 times. Since it is in the middle around the median and mean, it solidifies the thought that this data is very reliable and that menopausal age is where breast cancer is most likely to begin. The sample standard deviation for this data is 13.13. This is a very high standard deviation, as it allows for high chance for error in the ages. Although due to the data of age being discrete rather than continuous, standard deviation doesn’t work very well in justifying any of the data.
Conclusion
In conclusion, age is probably the biggest risk factor for breast cancer for many reasons. One of those reasons is that people who are older theoretically are exposed to more radiation and environmental chemicals and substances that cause breast cancer and mutations in cells. Cell microenvironments begin to complement the needs of mutations over time, and chronic inflammations make mutations harder to repair and check, and cause DNA damage. Mutations occur when cells aren’t checked and repaired properly if DNA is copied incorrect, and a tumour is caused when multiple cells in a small area are mutated and spilt causing more mutated cells that begin to overpower the area, the older a individual is, the more chances there are for that person to develop a tumour, especially in a smaller area such as the breast. Hormones such as oestrogen cause increase in potential mutation reproduction, and so does being nulliparous. However, having children increases the short-term risk of generating breast cancer, but decreases the long-term risk of it, and gives a bigger decrease in risk of developing breast cancer the younger an individual is to get pregnant and give birth. Menopause also increases the risk due to people taking hormone supplements around that age to neglect the side effects of menopause. The data also shows that ages 40 to 59 are where females develop breast cancer most, however there is also a lot between ages 60 to 69. All the analysis also suggests age is a leading risk factor of breast cancer. To lower the risk of breast cancer, an individual should be exercising, eating healthy and making sure there sleep schedules are well planned and carried out well.
Risk Factor – Diabetes
Research
Diabetes mellitus, otherwise known, as diabetes is a set of diseases characterised by high levels of glucose in the blood. Most of what is in our diet and what we digest is broken down into glucose, which is a form of sugar in the blood that is used as our main source of fuel for our bodies. When humans digest food, glucose makes its way into the bloodstream and our cells use it for energy and growth. However, it cannot enter the cell without insulin being present. Insulin is a hormone that is produced by the pancreas, and is automatically released by the pancreas to move glucose present in our blood into cells. Blood glucose levels drop immediately after glucose enters the cells. Diabetes occurs when insulin production is inadequate, or when the body’s cells do not respond properly to insulin, or a combination of both. There are two main types of diabetes, type one and two. Type one diabetes, sometimes referred to as insulin-dependent diabetes, juvenile or early-onset diabetes, is where the body doesn’t produce insulin. People normally develop type one diabetes before they are 40 years old, in early adulthood and sometimes during teenage years. There is no cure for this type of diabetes, so they must live their whole lives controlling their blood sugar levels with a combination of medication and proper diet. They have insulin therapy in the form if medications and for dire situations an EpiPen injection. Type two diabetes is where the body doesn’t produce enough insulin to function properly, or your body resists the effects of insulin, where your body produces it’s own antibodies against them and attacks them, otherwise known as insulin resistance. Symptoms to type two diabetes often take long to develop, and they include; weight loss, as without the ability to metabolise glucose, the body used it’s alternate fuel source, which is muscle and fats, and calories are lost as excess glucose is released in the urine. Fatigue, as if your cells are deprived of sugar, you may become tired or irritable. Areas of darkened skin can be observed in the folds and creases of their bodies, usually in the armpit or neck. This condition is called acanthosis nigricans, and it may be a sign of insulin resistance. Both type one and two diabetes have risk factors such as weight, inactivity and a family history.
Many studies have investigated whether diabetes and insulin treatment increase breast cancer risk or may affect prognosis. Women with diabetes have a 20% increased risk of breast cancer compared to woman without diabetes, however no impact has been shown when using insulin treatment has been found. Moreover, the overall death rate after breast cancer diagnosis has been shown to be 30% to 60% higher in women with diabetes compared to women without diabetes. Overall, studies that investigated the association between breast cancer-specific mortality and diabetes have inconsistent results. Diabetes itself might have a direct effect on breast cancer prognosis due to physiological effects of hyperglycaemia or hyperinsulinemia, which is part of insulin resistance observed in patients with type two diabetes. It is suggested that cancer survival decreases with a type of diabetes, and that fasting lowers insulin rates, and can lead to death dependent on body mass index. Another reason for the lower breast cancer survival rate could be that women with diabetes develop a more aggressive or less treatment-responsive tumour subtype. It has been shown that hormone-related breast cancer diabetes risk factors, such as obesity, are associated with the development of oestrogen receptor negative breast cancer. Furthermore, the promotion of tumour cell growth upon insulin exposure may differ by breast cancer subtype.
Data Pie Chart: This is a pie chart that shows how many patients out of 80 have diabetes, and how many of those died.
Analysis
As you can see from the graph, out of 80 patients who suffer from breast cancer, 55 of them don’t have diabetes, which is more than half, and this suggests that diabetes is not a large risk factor. The other 25 people did have diabetes, which suggests it could be an intermediate risk factor. However, looking at the mortality rates, 10 of the 25 people with diabetes died, which shows how it could increase mortality rate of breast cancer, as more than a third of them did not survive, and if you compare that to the amount dead who didn’t have diabetes, which is 3 out of 55, it shows that there is a large increase. This confirms the suggestion that diabetes correlates to increased risk of mortality when accompanied by breast cancer. There are no mathematical processes that could work with this to show validity, as there is no independent variable.
Conclusion
In conclusion, diabetes is a bad illness, which makes our body not be able to naturally control our blood sugar levels, either by stopping production of insulin, or by making it get targeted by our immune system, in type one and two diabetes. An individual can develop diabetes through their diet, genetics or even lack of physical activity. Diabetes was not shown or proven to increase risk of the manifestation of breast cancer, however, it was suggested to increase the risk of mortality when paired up with breast cancer. Although there is proof towards this, it is mostly inconsistent and cannot be accepted.
In conclusion, cancer is one of the most common cancers in women, and has one of the highest mortality rates for cancers. This essay suggested two different risk factors for breast cancer, one for developing it, and one for death risks.
