Risk Factors For Cancer

Risk Factors For Cancer
Cancer is a group of more than 100 different diseases, each with its own unique set of risk factors. Risk factors are elements that increase the possibility of developing a specific disease or condition. Over a lifetime, it is estimated that one in three people will develop cancer, according to the National Cancer Institute (NCI).

Cancer develops as a result of an uncontrolled growth of cells. In normal cell function, cells divide and die in an organized fashion. As cells grow old, they die, allowing for new cells to take their place. When old cells do not die and the body continues to create new cells, they collect to form a tumor. A tumor can be either benign (noncancerous) or malignant (cancerous).

There is more than one risk factor for most cancers. Some risk factors can be controlled, such as lifestyle habits. These factors can include smoking, alcohol use, diet and exercise. Other risk factors cannot be controlled by an individual, such as age, race, sex and genetic factors.

Although risk factors may be divided into controllable and uncontrollable categories, such distinctions may be counterproductive. In many cases, an environmental risk factor may combine with a genetic predisposition and create an opportunity for cancer to develop. Researchers believe that the development of cancer often involves environmental factors that directly or indirectly alter cells. These experts contend that nearly all cancers occur as a result of a combination of factors and it is nearly impossible to determine a single cause. Controllable and uncontrollable factors can combine to a point where identifying one or the other as the exact cause is extremely difficult.

The division of risk factors into categories may serve to provide better awareness for both patients and medical professionals. Awareness of controllable risk factors can help patients avoid them by quitting smoking, maintaining a healthy weight and protecting their skin from sun exposure. Awareness of both controllable and uncontrollable risk factors in a patient’s medical history provides physicians with valuable information to schedule screening tests and make diagnoses.

Many risk factors have been identified by scientists conducting epidemiological studies that analyze both environmental and genetic risk factors. According to the American Cancer Society, about 75 to 80 percent of cancers can be attributed to environmental factors, including tobacco use, diet, infectious agents and occupational exposure.

Much of this information has come from studying people who migrate from an area of high cancer risk to an area of low cancer risk (or vice versa). These migrant studies demonstrate that these people soon take on the cancer rates of their new area. Because genetic changes take several generations, it suggests that the cancer attack rates may be related to environmental causes.

Cancer Prevention

Cancer Prevention
1. Choose predominantly Plant based diets rich in fruits and Vegetables

2. Eat 400-800 grams a day of a variety of vegetables and fruits

3. It is preferable to eat fish and poultry. If eaten at all , limit intake of red meat. Do not eat charred food.

4. Limit consumption of fatty foods. Choose modest amounts of vegetable oils

5. Limit consumption of salted foods and use of cooking oil. Store perishable foods in ways that minimize fungal contamination.

6. Women has to practice regular self breast examination every month and mammography if indicated.

7. All women who had initiated Sexual activity has to undergo regular Cervical Smear (Pap smear) Screening.

8.Do not smoke or chew tobacco. Alcohol Consumption is not recommended.

9. Avoid being underweight or overweight.

10.If occupation activity is low, take an hours brisk walk or similar exercise daily.

Side Effects of Chemotherapy

Side Effects of Chemotherapy
Cancers are essentially known as malignant tumors wherein the morphology or infrastructure of the cells is distorted as compared to the corresponding normal cells. This is in variance with benign tumors, which have cells that closely resemble the infrastructure of the corresponding normal cells. In other words, the more the cells deviate from the normal makeup or appearance, the more malignant or aggressive the cancer.

1.Skin reactions
This complication is evidenced in intravenous drug administration. Sometimes, the drug may leak into the surrounding tissues and cause irritation. This may be experienced as a local burning sensation, pain and discomfort at the site of administration. However, this should not be neglected, and must be managed adequately as not doing so might lead to irreversible skin damage and possible death of the surrounding tissue.

2.Allergic reactions
A few chemotherapy agents may give rise to allergic or hypersensitivity reactions characterized by breathing difficulty, sweating, rashes, anxiety, palpitations, and fall in blood pressure. These reactions may occur from within 1 hr to 24hrs of receiving treatment.

3.Nausea/vomiting
These symptoms depend more or less on the doses of drugs, the drug schedule and route of administration. Pre-chemotherapy anxiety may also contribute to nausea and vomiting.

4.Fever/infection
Any rise in temperature of the body is regarded as a tell-tale sign of hidden infection. This is predominantly due to the so called “low counts” as a result of chemotherapy. It can be expected during day 7-14 of the cycle as this is the duration of fall in blood counts, keeping in mind that day 1 is the first day of receiving the chemo medicine.

5.Discoloration
Darkening of the skin, nail beds, tongue, and gums may be seen. This is evidenced mostly after 3-4 cycles of chemotherapy, and is more common in patients receiving chemotherapy in combination with radiotherapy.

6.Hair loss
This is one of the more heartbreaking effects seen with most chemotherapy regimens. It is mostly encountered after the 2-3rd cycle of treatment. However, it all depends on the dose, schedule, and number of cycles of chemotherapy. But the good news is that it is a reversible change as hair will grow once the treatment is completed, although the texture or color may differ.

7.Effect on the gut
Starting from the mouth, denudation or erosion of the membrane cells may render the body vulnerable to infections caused by the commensals or the good bacteria which are otherwise normally present without harming the host. Hence, one becomes immunocompromised or susceptible to infections more often than the normal individual. All this may lead to a spectrum of conditions ranging from oral ulcers, fungal infections, to diarrhea, which in turn may lead to dehydration if adequate and timely care is not taken.

8.Constipation
This is one of the most common side-effects encountered in patients receiving chemotherapy. Interestingly, it may be due to the disease condition itself which causes debility, immobility, metastasis or spread of cancer to the gut. It could also be due to narcotic painkillers used for pain alleviation, or dehydration due to decreased fluid intake.

9.Fatigue
General weakness, tiredness and fatigue may be experienced during the treatment or course of chemotherapy.

10.Malnutrition
This may be a result of anorexia or loss of appetite, which is one of the symptoms of cancer itself, but chemotherapy may add to it by causing alteration of taste, mouth sores, dislike of food, diarrhea or constipation. Malnutrition may result in poorer response to the treatment, and have a deleterious effect on the overall health of the individual.

11.Effect on nervous system
Certain chemo drugs may have a neurotoxic component and may result in altered state of consciousness, altered gait, hearing loss, or tingling in hands and feet. These effects are usually temporary, but need attention if long lasting.

12.Effect on reproductive system:
Although this is a late complication of chemotherapy, one needs to know that during treatment, a low sperm count may be anticipated.

13.Secondary cancer
One of the rare complications documented is that certain chemo drugs may give rise to genetic mutations resulting in secondary cancers.

All the above stated effects can be managed effectively and prevented by taking certain precautions as the benefits of cancer treatment are usually overwhelming when compared to the side-effects.

Bone cancer

Bone cancer
Information:
Bone cancer is caused by an abnormal and uncontrolled growth of cells within the bone. It can be benign or malignant.
Benign tumours aren't cancerous. They don't spread to other parts of the body and don't invade surrounding tissue.
Malignant tumours are cancerous. They spread to other parts of the body and invade surrounding tissue. This spread of cancer is called a metastasis and can form a secondary cancer in another organ.

Symptoms:
Most Common Symptoms:
1.osteosarcoma is most common in the lower thigh, shins and arms
2.Ewing's sarcoma most commonly occurs in the pelvis, thigh and shin
3.chondrosarcoma is most common in the thigh, pelvis, ribs, upper arm and shoulder bone.
4.spindle cell sarcoma most commonly develops in the lower thigh, shins and arms
Bone cancer often causes pain and tenderness in the affected area. This is often worse at night. As the cancer grows it can also cause swelling in the affected area. If it is near a joint it may make movement in that area difficult.
Less common symptoms:
1.tiredness
2.fever
3.weight loss
It's important to remember that these symptoms can be caused by many problems other than bone cancer. So although not necessarily a result of bone cancer, if you have these symptoms you should visit your GP.

Causes:
1.Previous treatment with radiotherapy. If you have had a lot of radiotherapy for cancer in the past, you have a slightly increased risk of getting bone cancer in that area.
2.Paget's disease. This bone disease gradually deforms your bones, causing pain and fractures. Having Paget's disease for a long time increases your risk of developing bone cancer
3.Having a previous benign bone tumour. If you have had a benign (non-spreading) type of bone cancer, you are more likely to develop chondrosarcoma.
4.Retinoblastoma. Inheriting the gene that causes this rare type of eye cancer also makes you more likely to develop osteosarcoma.
5.Having certain other rare inherited conditions, such as Li-Fraumeni syndrome, can increase your risk of developing bone cancer.

Treatment:
a.Limb salvage surgery involves removing the area of bone where the tumour is. Because of the recent advances in surgery, this method of treating bone cancer is becoming more common. The area of bone removed is replaced with either a metal prosthesis (an artifical replacement part) or a piece of healthy bone taken from another part of your body (a bone graft).
b.Despite ongoing improvements in surgical technique, sometimes a limb salvaging operation isn't possible. If the cancer has spread into surrounding tissues, amputating the limb may be the only way to get rid of the cancer. Support from the medical staff looking after you can help you come to terms with this news. Advances in prosthetics (artificial limbs) mean that you can often have a fully active life after this surgery. A specialist in artificial limbs will visit you at hospital to arrange one for you. A physiotherapist will be able to teach you how to adapt to and best use it.

Non-surgical treatments
Chemotherapy

Chemotherapy uses medicines to destroy cancer cells. However, they can also have side effects such as making you feel tired or ill, or causing nausea or hair loss. Chemotherapy is particularly good at treating Ewing's sarcoma, but it can also treat other types of bone cancer such as osteosarcoma.

There are lots of different types of chemotherapy drugs. They are usually injected into a vein but sometimes tablets are used.

Chemotherapy is often given before and after surgery to make it easier to remove the tumour and to prevent it coming back.
Radiotherapy

Radiotherapy uses radiation to kill cancer cells. A beam of radiation is targeted on the cancerous cells, which shrinks the tumour.

Radiotherapy is especially useful for Ewing's sarcoma but it's sometimes used for osteosarcoma. It can be used before surgery to make it easier to remove the tumour, or afterwards to prevent it coming back.

Skin cancer

Skin cancer
Information:
Skin cancer is the most common form of human cancer. It is estimated that over 1 million new cases occur annually. The annual rates of all forms of skin cancer are increasing each year, representing a growing public concern. It has also been estimated that nearly half of all Americans who live to age 65 will develop skin cancer at least once.
Causes:
Exposure to sun: There is evidence that, in contrast to squamous cell carcinoma, basal cell carcinoma is promoted not by accumulated sun exposure but by intermittent sun exposure like that received during vacations, especially early in life. According to the U.S. National Institutes of Health, ultraviolet (UV) radiation from the sun is the main cause of skin cancer. The risk of developing skin cancer is also affected by where a person lives. People who live in areas that receive high levels of UV radiation from the sun are more likely to develop skin cancer. In the United States, for example, skin cancer is more common in Texas than it is in Minnesota, where the sun is not as strong. Worldwide, the highest rates of skin cancer are found in South Africa and Australia, which are areas that receive high amounts of UV radiation.

Age: Most skin cancers appear after age 50, but the sun's damaging effects begin at an early age. Therefore, protection should start in childhood in order to prevent skin cancer later in life.

Exposure to ultraviolet radiation in tanning booths: Tanning booths are very popular, especially among adolescents, and they even let people who live in cold climates radiate their skin year-round.

Therapeutic radiation, such as that given for treating other forms of cancer.

Symptoms:
Skin cancer causes the skin cells to grow and multiply abnormally. The cells are required to divide at a normal rate in order to regenerate new skin and replace the dead skin cells. When the skin cells start to multiply abnormally, they form a tumour, which eventually turns malignant and causes the cancer to spread to the lower levels of the skin and eventually the other organs of the body.

The first signs to look for when checking for the cancer is on the skin, in the form of a sore or a growth that refuse to heal. It also takes the form of a small lump sometimes that is; shiny or waxy in appearance. The sore is sometimes red, brown or black and is rough and scaly. The appearance of an excess number of moles is another sign to look out for. However not all spots , sores or moles are definite signs of cancer, therefore if you do find anything of your skin that causes concern, consult your doctor or a dermatologist to determine the exact cause of the growth. The doctor can then conduct a biopsy to determine the cancer if it does exist and then suggest the best possible treatment required.

Treatment:
Curettage and desiccation: Dermatologists often prefer this method, which consists of scooping out the basal cell carcinoma by using a spoon like instrument called a curette. Desiccation is the additional application of an electric current to control bleeding and kill the remaining cancer cells. The skin heals without stitching. This technique is best suited for small cancers in non-crucial areas such as the trunk and extremities.

Surgical excision: The tumor is cut out and stitched up.

Radiation therapy: Doctors often use radiation treatments for skin cancer occurring in areas that are difficult to treat with surgery. Obtaining a good cosmetic result generally involves many treatment sessions, perhaps 25 to 30.

Cryosurgery: Some doctors trained in this technique achieve good results by freezing basal cell carcinomas. Typically, liquid nitrogen is applied to the growth to freeze and kill the abnormal cells.

Mohs micrographic surgery: Named for its pioneer, Dr. Frederic Mohs, this technique of removing skin cancer is better termed "microscopically controlled excision." The surgeon meticulously removes a small piece of the tumor and examines it under the microscope during surgery. This sequence of cutting and microscopic examination is repeated in a painstaking fashion so that the basal cell carcinoma can be mapped and taken out without having to estimate or guess the width and depth of the lesion. This method removes as little of the healthy normal tissue as possible. Cure rate is very high, exceeding 98%. Mohs micrographic surgery is preferred for large basal cell carcinomas, those that recur after previous treatment, or lesions affecting parts of the body where experience shows that recurrence is common after treatment by other methods. Such body parts include the scalp, forehead, ears, and the corners of the nose. In cases where large amounts of tissue need to be removed, the Mohs surgeon sometimes works with a plastic (reconstructive) surgeon to achieve the best possible postsurgical appearance.

Medical therapy using creams that attack cancer cells (5-Fluorouracil--5-FU, Efudex, Fluoroplex) or stimulate the immune system (imiquimod [Aldara]). These are applied several times a week for several weeks. They produce brisk inflammation and irritation. The advantages of this method is that it avoids surgery, lets the patient perform treatment at home, and may give a better cosmetic result. Disadvantages include discomfort, which may be severe, and a lower cure rate, which makes medical treatment unsuitable for treating most skin cancers on the face.

Brain Tumer

Brain Tumer
Information:
A brain tumor is a mass of abnormal cells that is growing in or around the brain. It develops when abnormal cells multiply for unknown reasons. Benign and malignant are terms used to describe brain tumors. Benign brain tumors are usually slow growing and have distinct borders and a normal appearance under a microscope. Malignant tumors are considered brain cancer. They tend to invade healthy areas of the brain and may grow rapidly. A benign tumor may be considered malignant if it is located in a critical area of the brain or its size is life-threatening.

Causes:
Brain tumors are usually caused by a change in genetic structure, such as mutated or missing genes. This results in abnormal cells. If abnormal cells have malignant potential, they will form a tumor when they multiply.

Changes in genetic structure may be inherited, caused by the environment, or both. Overall, a low percentage (5%) of primary brain tumors are associated with inherited genes alone. However, certain types of brain tumors, such as glioblastoma multiforme, are often associated with inherited genes.

High-dose ionizing radiation, used to treat brain tumors, may on rare occasions be associated with the production of secondary brain tumors. This most often occurs from radiation treatments that are given over time. People exposed to certain chemicals, such as petrochemicals, pesticides and formaldehyde, appear to be at higher risk of developing a malignant brain tumor than those who are not exposed. In laboratory experiments, some viruses caused brain tumors in animals. It is unknown whether viruses can cause brain tumors in humans. While the general public believes that electromagnetic fields may be connected to brain tumors, there is no research showing such a relationship.


Symptoms:
Headaches
Headaches are a common initial symptom. Typical "brain tumor headaches" are often described as worse in the morning, with improvement gradually during the day. They may rouse the person from sleep. Sometimes, upon awakening, the person vomits then feels better. These headaches may worsen with coughing, exercise, or with a change in position such as bending or kneeling. They also do not typically respond to the usual headache remedies.

There are many causes, and types, of headaches. If you are experiencing headaches, we encourage to talk to your doctor. He or she is best able to listen to your concerns, outline your medical and headache history, and determine the next "best step" in your care. .

Seizures
About one-third of people diagnosed with a brain tumor are not aware they have a tumor until they have a seizure. Seizures are a common symptom of a brain tumor. Seizures are caused by a disruption in the normal flow of electricity in the brain. Those sudden bursts of electricity may cause convulsions, unusual sensations, and loss of consciousness. Focal seizures -- such as muscle twitching or jerking of an arm or leg, abnormal smells or tastes, problems with speech or numbness and tingling -- may also occur.

Mental and/or Personality Changes
These can range from problems with memory (especially short-term memory), speech, communication and/or concentration changes to severe intellectual problems and confusion. Changes in behavior, temperament and personality may also occur, depending where the tumor is located. These changes can be caused by the tumor itself, by increased pressure within the skull caused by the presence of the tumor, or by involvement of the parts of the brain that control personality.


Dignosis:
Computerized Tomography (CT): Computerized tomography (CT) or computerized axial tomography (CAT) scan is a series of detailed pictures of the brain, created by a computer linked to an X-ray machine. In some cases, a special dye is injected into a vein before the scan. The dye helps to show differences in the tissues of the brain
Magnetic Resonance Imaging (MRI): Magnetic resonance imaging (MR) provides pictures of the brain, using a powerful magnet linked to a computer. MRI is especially useful in diagnosing brain tumors because it can "see" through the bones of the skull to the tissue underneath. A special dye may be used to enhance the likelihood of detecting a brain tumor.

Secondary Tests:
Angiogram or Arteriogram: These tests are a series of X-rays taken after a special dye is injected into an artery, usually in the area where the abdomen joins the top of the leg. The dye, which flows through the blood vessels of the brain, can be seen on X-rays. These X-rays can show the tumor and connecting blood vessels.

Brain Scan: A brain scan reveals areas of abnormal growth in the brain and records them on special film. A small amount of a radioactive material is injected into a vein. This dye is absorbed by the tumor and the growth shows up on the film. The radiation leaves the body within 6 hours and is not dangerous.

Myelogram: A myelogram, sometimes called a lumbosacral spine X-ray , is an X-ray or computerized tomography (CT) scan of the spine. A special dye is injected into the cerebrospinal fluid in the spine and the patient is tilted to allow the dye to mix with the fluid. This test may be done when the doctor suspects a tumor in the spinal cord.
MR Spectroscopy:

Colon Cancer

Colon Cancer
Information:
The colon is the part of the digestive system where the waste material is stored. The rectum is the end of the colon adjacent to the anus. Together, they form a long, muscular tube called the large intestine (also known as the large bowel). Tumors of the colon and rectum are growths arising from the inner wall of the large intestine. Benign tumors of the large intestine are called polyps. Malignant tumors of the large intestine are called cancers. Benign polyps do not invade nearby tissue or spread to other parts of the body. Benign polyps can be easily removed during colonoscopy and are not life-threatening. If benign polyps are not removed from the large intestine, they can become malignant (cancerous) over time. Most of the cancers of the large intestine are believed to have developed from polyps. Cancer of the colon and rectum (also referred to as colorectal cancer) can invade and damage adjacent tissues and organs.

Causes:
Diet
Diets high in fat are believed to predispose humans to colorectal cancer. In countries with high colorectal cancer rates, the fat intake by the population is much higher than in countries with low cancer rates. It is believed that the breakdown products of fat metabolism lead to the formation of cancer-causing chemicals (carcinogens).

Ulcerative colitis and colon cancer
Chronic ulcerative colitis causes inflammation of the inner lining of the colon. For further information, please read the Ulcerative Colitis article. Colon cancer is a recognized complication of chronic ulcerative colitis. The risk for cancer begins to rise after eight to 10 years of colitis. The risk of developing colon cancer in a patient with ulcerative colitis also is related to the location and the extent of his or her disease.
Current estimates of the cumulative incidence of colon cancer associated with ulcerative colitis are 2.5% at 10 years, 7.6% at 30 years, and 10.8% at 50 years. Patients at higher risk of cancer are those with a family history of colon cancer, a long duration of colitis, extensive colon involvement, and those with primary sclerosing cholangitis (PSC).

Genetics and colon cancer
A person's genetic background is an important factor in colon cancer risk. Among first-degree relatives of colon cancer patients, the lifetime risk of developing colon cancer is 18% (a threefold increase over the general population in the United States).
Even though family history of colon cancer is an important risk factor, majority (80%) of colon cancers occur sporadically in patients with no family history of colon cancer. Approximately 20% of cancers are associated with a family history of colon cancer. And 5 % of colon cancers are due to hereditary colon cancer syndromes.
Hereditary colon caner syndromes are disorders where affected family members have inherited cancer-causing genetic defects from one or both of the parents.
Chromosomes contain genetic information, and chromosome damages cause genetic defects that lead to the formation of colon polyps and later colon cancer. In sporadic polyps and cancers (polyps and cancers that develop in the absence of family history), the chromosome damages are acquired (develop in a cell during adult life). The damaged chromosomes can only be found in the polyps and the cancers that develop from that cell. But in hereditary colon cancer syndromes, the chromosome defects are inherited at birth and are present in every cell in the body. Patients who have inherited the hereditary colon cancer syndrome genes are at risk of developing large number of colon polyps, usually at young ages, and are at very high risk of developing colon cancer early in life, and also are at risk of developing cancers in other organs.

Symptoms:
Symptoms of colon cancer are numerous and nonspecific. They include fatigue, weakness, shortness of breath, change in bowel habits, narrow stools, diarrhea or constipation, red or dark blood in stool, weight loss, abdominal pain, cramps, or bloating. Other conditions such as irritable bowel syndrome (spastic colon), ulcerative colitis, Crohn's disease, diverticulosis, and peptic ulcer disease can have symptoms that mimic colorectal cancer. For more information on these conditions, please read the following articles: Irritable Bowel Syndrome, Ulcerative Colitis, Crohn's Disease, Diverticulosis, and Peptic Ulcer Disease.
Therapy:
Chemotherapy is the use of medications to kill cancer cells. It is a systemic therapy, meaning that the medication travels throughout the body to destroy cancer cells. After colon cancer surgery, some patients may harbor microscopic metastasis (small foci of cancer cells that cannot be detected). Chemotherapy is given shortly after surgery to destroy these microscopic cells. Chemotherapy given in this manner is called adjuvant chemotherapy. Recent studies have shown increased survival and delay of tumor recurrence in some patients treated with adjuvant chemotherapy within five weeks of surgery. Most drug regimens have included the use of 5-flourauracil (5-FU). On the other hand, chemotherapy for shrinking or controlling the growth of metastatic tumors has been disappointing. Improvement in the overall survival for patients with widespread metastasis has not been convincingly demonstrated.

Radiation therapy:
Radiation therapy in colorectal cancer has been limited to treating cancer of the rectum. There is a decreased local recurrence of rectal cancer in patients receiving radiation either prior to or after surgery. Without radiation, the risk of rectal cancer recurrence is close to 50%. With radiation, the risk is lowered to approximately 7%. Side effects of radiation treatment include fatigue, temporary or permanent pelvic hair loss, and skin irritation in the treated areas.