Cancer

Answer 1

ancer is a complex and devastating group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body. It can affect virtually any part of the body and has the potential to invade nearby tissues and even metastasize to distant organs, making it a major cause of illness and mortality worldwide.

The development of cancer is typically driven by genetic mutations and various risk factors, such as exposure to carcinogens, genetic predisposition, and lifestyle choices.

The treatment of cancer often involves a combination of approaches, including surgery, chemotherapy, radiation therapy, immunotherapy, and targeted therapies, with the choice of treatment depending on the type and stage of cancer.

Early detection and prevention strategies, such as regular screenings and lifestyle modifications, are critical in the fight against cancer, as they can improve the chances of successful treatment and, in some cases, prevent its occurrence altogether. Research into cancer Biology and treatment continues to advance, offering hope for more effective and personalized treatments in the future.

Answer 2

Definition

Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.

Alternative Names

Carcinoma; Malignant tumor

Causes, incidence, and risk factors

Cells are the building blocks of living things. Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells "forget" how to die.

There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.

There are many causes of cancers, including:

• Benzene and other chemicals
• Certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
• Certain viruses
• Radiation
• Sunlight
• Tobacco

However, the cause of many cancers remains unknown.

The most common cause of cancer-related death is lung cancer.

The three most common cancers in men in the United States are:

• Prostate cancer
• Lung cancer
• Colon cancer

In women in the United States, the three most common cancers are:

• Breast cancer
• Colon cancer
• Lung cancer

Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of gastric cancer, but in the United States, this type of cancer is pretty rare. Differences in diet may play a role.

Some other types of cancers include:

• Brain cancer
• Cervical cancer
• Hodgkin's lymphoma
• Kidney cancer
• Leukemia
• Liver cancer
• Non-Hodgkin's lymphoma
• Ovarian cancer
• Skin cancer
• Testicular cancer
• Thyroid cancer
• Uterine cancer

Symptoms

Symptoms of cancer depend on the type and location of the tumor. For example, lung cancer can cause coughing, shortness of breath, or chest pain. Colon cancer often causes diarrhea, constipation, and blood in the stool.

Some cancers may not have any symptoms at all. In certain cancers, such as gallbladder cancer, symptoms often do not start until the disease has reached an advanced stage.

The following symptoms can occur with most cancers:

• Chills
• Fatigue
• Fever
• Loss of appetite
• Malaise
• Night sweats
• Weight loss

Signs and tests

Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common tests include the following:

• Biopsy of the tumor
• Blood chemistries
• Bone marrow biopsy (for lymphoma or leukemia)
• Chest x-ray
• Complete blood count (CBC)
• CT scan

Most cancers are diagnosed by biopsy. Depending on the location of the tumor, the biopsy may be a simple procedure or a serious operation. Most patients with cancer have CT scans to determine the exact location and size of the tumor or tumors.

A cancer diagnosis is difficult to cope with. It is important, however, that you discuss the type, size, and location of the cancer with your doctor when you are diagnosed. You also will want to ask about treatment options, along with their benefits and risks.

It's a good idea to have someone with you at the doctor's office to help you get through the diagnosis. If you have trouble asking questions after hearing about your diagnosis, the person you bring with you can ask them for you.

Treatment

Treatment also varies based on the type of cancer and its stage. The stage of a cancer refers to how much it has grown and whether the tumor has spread from its original location.

• If the cancer is confined to one location and has not spread, the most common goals for treatment are surgery and cure. This is often the case with skin cancers, as well as cancers of the lung, breast, and colon.
• If the tumor has spread to local lymph nodes only, sometimes these can also be removed.
• If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both. Some cancers require a combination of surgery, radiation, and chemotherapy.

Although treatment for cancer can be difficult, there are many ways to keep up your strength.

If you have radiation treatment, know that:

• Radiation treatment is painless.
• Treatment is usually scheduled every weekday.
• You should allow 30 minutes for each treatment session, although the treatment itself usually takes only a few minutes.
• You should get plenty of rest and eat a well-balanced diet during the course of your radiation therapy.
• Skin in the treated area may become sensitive and easily irritated.
• Side effects of radiation treatment are usually temporary. They vary depending on the area of the body that is being treated.

If you are going through chemotherapy, you should eat right. Chemotherapy causes your immune system to weaken, so you should avoid people with colds or the flu. You should also get plenty of rest, and don't feel as though you have to accomplish tasks all at once.

It will help you to talk with family, friends, or a support group about your feelings. Work with your health care providers throughout your treatment. Helping yourself can make you feel more in control.

Support Groups

A cancer diagnosis often causes a lot of anxiety and can affect your entire quality of life. Several support groups for cancer patients can help you cope.

Expectations (prognosis)

The outlook depends on the type of cancer. Even among people with one type of cancer, the outcome varies depending on the stage of the tumor when they are diagnosed.

Some cancers can be cured. Some cancers that are not curable can still be treated well. And some patients can live for many years with their cancer. Other tumors are quickly life-threatening.

Complications

One complication is that the cancer may spread. Other complications vary with the type and stage of the tumor.

Calling your health care provider

Contact your health care provider if you develop symptoms of cancer.

Prevention

One of the best ways to prevent cancer is to not smoke or chew tobacco. Many cancers can be prevented by avoiding risk factors such as excessive exposure to sunlight and heavy drinking.

Cancer screenings, such as mammography and breast examination for Breast cancer and colonoscopy for colon cancer, may help catch these cancers at their early stages when they are most treatable. Some people at high risk for developing certain cancers can take medication to reduce their risk.

Answer 3

Definition

Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.

Alternative Names

Carcinoma; Malignant tumor

Causes, incidence, and risk factors

Cells are the building blocks of living things.

Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells forget how to die.

There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.

There are many causes of cancers, including:

• Benzene and other chemicals
• Drinking excess alcohol
• Environmental toxins, such as certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
• Excessive sunlight exposure
• Genetic problems
• Obesity
• Radiation
• Viruses

However, the cause of many cancers remains unknown.

The most common cause of cancer-related death is lung cancer.

The three most common cancers in men in the United States are:

• Prostate cancer
• Lung cancer
• Colon cancer

In women in the United States, the three most common cancers are:

• Breast cancer
• Colon cancer
• Lung cancer

Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of stomach cancer, but in the United States, this type of cancer is pretty rare. Differences in diet may play a role.

Some other types of cancers include:

• Brain cancer
• Cervical cancer
• Hodgkin's lymphoma
• Kidney cancer
• Leukemia
• Liver cancer
• Non-Hodgkin's lymphoma
• Ovarian cancer
• skin cancer
• Testicular cancer
• Thyroid cancer
• Uterine cancer

Symptoms

Symptoms of cancer depend on the type and location of the cancer. For example, lung cancer can cause coughing, shortness of breath, or chest pain. Colon cancer often causes diarrhea, constipation, and blood in the stool.

Some cancers may not have any symptoms at all. In certain cancers, such as pancreatic cancer, symptoms often do not start until the disease has reached an advanced stage.

The following symptoms can occur with most cancers:

• Chills
• Fatigue
• Fever
• Loss of appetite
• Malaise
• Night sweats
• Weight loss

Signs and tests

Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common tests include the following:

• Biopsy of the tumor
• Blood tests (which look for chemicals such as tumor markers)
• Bone marrow biopsy (for lymphoma or leukemia)
• Chest x-ray
• Complete blood count (CBC)
• CT scan
• MRI scan

Most cancers are diagnosed by biopsy. Depending on the location of the tumor, the biopsy may be a simple procedure or a serious operation. Most patients with cancer have CT scans to determine the exact location and size of the tumor or tumors.

A cancer diagnosis is difficult to cope with. It is important, however, that you discuss the type, size, and location of the cancer with your doctor when you are diagnosed. You also will want to ask about treatment options, along with their benefits and risks.

It's a good idea to have someone with you at the doctor's office to help you get through the diagnosis. If you have trouble asking questions after hearing about your diagnosis, the person you bring with you can ask them for you.

Treatment

Treatment varies based on the type of cancer and its stage. The stage of a cancer refers to how much it has grown and whether the tumor has spread from its original location.

• If the cancer is confined to one location and has not spread, the most common treatment approach is surgery to cure the cancer. This is often the case with skin cancers, as well as cancers of the lung, breast, and colon.
• If the tumor has spread to local lymph nodes only, sometimes these can be removed.
• If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both. Some cancers require a combination of surgery, radiation, and chemotherapy.
• Lymphoma, or cancer of the lymph glands, is rarely treated with surgery. Chemotherapy and radiation therapy are most often used to treat lymphoma.

Although treatment for cancer can be difficult, there are many ways to keep up your strength.

If you have radiation treatment, know that:

• Radiation treatment is painless.
• Treatment is usually scheduled every weekday.
• You should allow 30 minutes for each treatment session, although the treatment itself usually takes only a few minutes.
• You should get plenty of rest and eat a well-balanced diet during the course of your radiation therapy.
• Skin in the treated area may become sensitive and easily irritated.
• Side effects of radiation treatment are usually temporary. They vary depending on the area of the body that is being treated.

If you are going through chemotherapy, you should eat right. Chemotherapy causes your immune system to weaken, so you should avoid people with colds or the flu. You should also get plenty of rest, and don't feel as though you have to accomplish tasks all at once.

It will help you to talk with family, friends, or a support group about your feelings. Work with your health care providers throughout your treatment. Helping yourself can make you feel more in control.

Support Groups

The diagnosis and treatment of cancer often causes a lot of anxiety and can affect a person's entire life. There are many resources for cancer patients.

See: Cancer resources

Expectations (prognosis)

The outlook depends on the type of cancer. Even among people with one type of cancer, the outcome varies depending on the stage of the tumor when they are diagnosed.

Some cancers can be cured. Other cancers that are not curable can still be treated well. Some patients can live for many years with their cancer. Other tumors are quickly life-threatening.

Complications

One complication is that the cancer may spread. Other complications vary with the type and stage of the tumor.

Calling your health care provider

Contact your health care provider if you develop symptoms of cancer.

Prevention

You can reduce the risk of getting a cancerous (malignant) tumor by:

• Eating a healthy diet
• Exercising regularly
• Limiting alcohol
• Maintaining a healthy weight
• Minimizing your exposure to radiation and toxic chemicals
• Not smoking or chewing tobacco
• Reducing sun exposure, especially if you burn easily

Cancer screenings, such as mammography and breast examination for breast cancer and colonoscopy for colon cancer, may help catch these cancers at their early stages when they are most treatable. Some people at high risk for developing certain cancers can take medication to reduce their risk.

References

Moscow JA, Cowan KH. Biology of cancer. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 187.

Thun MJ. Epidemiology of cancer. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 185.

Reviewed By

Review Date: 08/14/2010

David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

Answer 4

The following 12 symptoms of cancer require immediate attention. the earlier cancer is detected, the more diverse the treatment options are, the higher the probabilities of recovery.

For more information on the signs of cancer