An Overview of Cancer

What exactly is cancer, how does it start, and why does it grow and spread? What else should I know about cancer? Let's discuss the basics and remove some of the mystery behind this frightening disease. One in two men and one in three women are expected to develop cancer (not including skin cancer) over the course of a lifetime.

What Is Cancer?

Cancer is a group of over 200 different diseases, which begin when a single cell in the body fails to obey the normal rules of cell growth.

Instead of ceasing growth at some point, and dying off when old or damaged, these cells achieve a state of "immortality" and continue to grow, even it damages the cells and organ in which it began.

Cancer cells differ from normal cells in many ways, and understanding some of these differences may help you understand more about how cancer behaves.

How Does Cancer Begin?

It actually not easy for a cell to become a cancer cell, and as you listen to the latest hype about a new cause of cancer, you may feel some reassurance in hearing what is necessary for this change to occur.

In order for a cell to become cancerous, it usually needs to undergo a series of gene mutations. These mutations and other genetic changes take place in the DNA which is present in the nucleus of each of our cells.

The DNA in our cells acts as a genetic blueprint, carrying the instructions for proteins that regulate all the processes of the cell. When this DNA is damaged, for example, by a carcinogen in the environment or through a mistake in the normal reproduction of cells, the damaged genes then code for damaged proteins. When these damaged proteins have functions related to cell growth, a cancer may occur.

Not all mutations result in cancer. Mutations in three types of genes (often together) called "driver mutations" are often needed to disrupt the normal growth and division of cells enough so that a cancer develops. These three types of genes are proto-oncogenes, tumor suppressor genes, and DNA repair genes. 

Proto-oncogenes are like the accelerator on a car. Mutations in these genes are similar to laying your foot on the accelerator and not letting up. The cells continue to divide even though there is no need for further cells. In contrast, tumor suppressor genes are like brakes on the car. A mutation in one of these genes is similar to taking your foot off of the brakes when you are speeding downhill. The cell grows out of control. DNA repair genes are responsible for repairing damaged DNA or removing the cells (through a process of programmed cell death called apoptosis.) In contrast to normal cells which are repaired or taken out of service when they are old or damaged, the abnormal cells are allowed to grow and flourish.

Understanding the genetic basis of cancer is helpful in understanding a genetic predisposition to cancer. An example is the BRCA1 and BRCA2 mutations, which are associated with some hereditary breast cancers. BRCA2 is a tumor suppressor gene that is autosomal recessive—if one copy of the gene is mutated, nothing happens, but if both copies of this gene are mutated, a cancer may develop. If a woman (or man) is born with a mutation in one of these genes, it does not mean that she will develop cancer for certain. It just means that she is more likely to develop cancer if a mutation in the other copy of this gene, or in other genes responsible for driving the growth of the cell, occurs.

The ability to determine some of the genetic mutations present in a specific tumor is the basis for many of the newer targeted therapies and the growth of what has been coined personalized medicine or precision medicine.

How Does Cancer Grow and Spread?

Just as there are differences in cancer cells which cause them to grow out of control, there are differences between benign and malignant tumors.

Unlike benign tumors, malignant (cancerous) tumors can invade nearby tissues and spread to distant tissues. The word cancer is actually derived from a word meaning crab, referring to the crablike extension of cancer into adjacent tissues.

The spread of cancer to regions apart from the original location of the tumor; something referred to as metastasis—is a cardinal feature of cancer, and is responsible for roughly 90 percent of deaths from cancer. Normal cells are "sticky;" they are influenced by "adhesion molecules" which hold the cells together like glue. In contrast, cancer cells, lacking these molecules, can break away from the primary tumor and travel.

There are a few methods by which cancer spreads. Cancer cells may enter the bloodstream or lymphatic vessels to travel to other regions of the body. In the case of lung cancer, they may spread through the airways as well.

Where Does Cancer Spread?

As noted above, it is the spread of cancer which causes of the majority of deaths from cancer.

Sometimes a cancer is found when it has already spread to another region of the body. These cancers are still named after the organ in which they originate. For example, if a lung cancer is found only after discovering metastases in the brain, it would not be called brain cancer. Instead, it would be referred to as "lung cancer metastatic to the brain."

The most common sites of metastasis overall include the bones, the liver, and the lungs. Breast cancer often spreads to the bones, the brain, the liver, and the lungs. The most common sites for lung cancer metastasis are the adrenal glands, the bones, the brain, and the liver. For colon cancer, metastasis occurs most often to the liver, lungs, and peritoneum, and prostate cancer usually first spreads to the adrenal glands, the bones, the liver, and the lungs.

After Cancer Spreads

After a tumor spreads to another region of the body there are differences between normal cells and cancer cells as well. In order to grow, a tumor needs a blood supply. This process of angiogenesis—developing a system of blood vessels that nourish the tumor and allow it to grow—is an important focus of some cancer treatments, and "angiogenesis inhibitors" are currently being used for several types of cancer.

What Causes Cancer?

As noted above, for a normal cell to become a cancer cell, a series of gene mutations need to take place. Understanding the possible causes of cancer, and risk factors for cancer is easier to understand if you consider the mechanism by which this happens. These may include:

  • Direct damage to DNA - Some substances and exposures can directly damage the DNA in our cells. An example would be radiation directly damaging DNA in the nucleus of the cell.
  • Chronic inflammation - Whenever cells reproduce and divide, there is a chance that an accident will occur. In other words, that a DNA mutation will occur. Chronic inflammation, such as that in the respiratory tree or esophagus related to smoking, may result in cancer by increasing the chance that a mistake in cell division will occur.

Risk Factors for Cancer

As noted above, cancer occurs when a series of mutations take place in the DNA in the nucleus of the cell. We don’t know exactly how this takes place, but we do know of several risk factors that account for cells becoming cancer cells. These can be broken own to include:

  • Lifestyle factors - Smoking is the single most important cause of cancer. Smoking causes many different types of cancer and is responsible for nearly a third of cancer deaths. Drinking excess alcohol is implicated in many cancers. And obesity increases the risk of several cancers. Starting with a 60 percent increase in uterine cancer risk, obesity may soon surpass smoking as the leading preventable cause of cancer.
  • Environmental exposuresRadon exposure causes cancer and having an elevated level of this gas in your home is the second most common cause of lung cancer. Work-related exposures to cancer-causing substances (carcinogens) is an important cause of cancer in men, but increasingly, in women as well.
  • Genetics - A genetic predisposition to cancer can occur when people inherit a mutation in a gene responsible for removing damaged cells (tumor suppressor genes) and more. The public is well informed that breast cancer may have a hereditary component, but what's less well known is that this can be the case with many cancers. Learn about your genetic blueprint and how it affects your cancer risk.
  • Viruses and other microorganismsViruses are an important cause of cancer, responsible for roughly 25 percent of cancers worldwide, and 5 to 10 percent of cancers in the U.S. Infection with human papillomavirus (HPV) is a reminder that unsafe sex can predispose to more than pregnancy. This virus is the cause of most cervical cancers as well as cancers of the vagina, penis, and half of head and neck cancers. It's now thought that infection with H pylori, the bacteria implicated in many ulcers, is the cause of many stomach cancers in the United States. And chronic infections with either the hepatitis B or hepatitis C virus are significant causes of liver cancer.

Types of Cancer – Common and Rare

There are over 200 different types of cancer, named for the tissue type or organ in which they begin. Some of these are very common, for example, one in seven men are expected to develop prostate cancer, and some are very rare, occurring in only a few people each year.

Common Types of Cancer in Men and Women

You may be confused when you hear of statistics talking about common cancers. For example, you may hear one source speak of breast cancer as being most common in women, and others speak of lung cancer as the most common. The problem is that these statistics may be quoting two different things; the incidence of the cancer or how often it occurs, and the mortality of a cancer, how many people die from that cancer each year.

For cancers that have high survival rates, the incidence may be high but the mortality rate may be low. In contrast, for cancers with lower survival rates, such as pancreatic cancer, the incidence may not be high but it may be one of the more common causes of deaths from cancer.

The 10 most common cancers (excluding skin cancers such as squamous cell carcinoma and basal cell carcinoma) based on both their incidence and their mortality are listed below.

The top 10 most common cancers to occur (incidence of new cases in men and women combined) include: 

  1. Breast cancer
  2. Lung cancer
  3. Prostate
  4. Colon cancer
  5. Bladder
  6. Melanoma
  7. Non-Hodgkin lymphoma
  8. Thyroid
  9. Kidney
  10. leukemia

The 10 most common causes of cancer-related deaths include:

  1. Lung cancer
  2. Colon (and rectal) cancer
  3. Breast
  4. Pancreatic
  5. Prostate
  6. Leukemia
  7. Non-Hodgkin lymphoma
  8. Bladder
  9. Kidney
  10. Endometrial (uterine)

The 10 most fatal cancers in men differ from the 10 most fatal cancers in women, and these numbers can vary as well based on the age of diagnosis and other factors.

Most Common Cancers Overall

Lung Cancer

When asked about cancer deaths, a study found that the majority of people thought that breast cancer was the leading killer in women and prostate cancer in men. In fact, the leading cause of cancer deaths in both men and women is lung cancer. And while smoking is a risk factor for lung cancer, lung cancer occurs in non-smokers as well. Lung cancer in never smokers is now the 6th leading cause of cancer-related deaths overall.  As the number of people who smoke has decreased, there has been a decrease in lung cancer as well in recent years. That said, lung cancer appears to be increasing in non-smokers (never smokers) especially young never-smoking women.

Lung cancer carries not only the stigma that it is a smoker's disease, but that it is uniformly fatal. Thankfully, after many years of little progress in the treatment of this disease, new therapies have been approved which have raised the survival rate, even for some people with the most advanced stages of the disease. Everyone with non-small cell lung cancer—the most common type of the disease—should now have molecular profiling (gene testing) on their tumors.

Due to the stigma of lung cancer being due to smoking, many people are unaware of simple steps they can take to lower their risk. Radon exposure in our homes is the second leading cause of lung cancer and is easy to test for and resolve if it is present. Anyone could be at risk, and the only way to know is to test your home.

Breast cancer

Breast cancer is the most common type of cancer in women and is the second leading cause of cancer-related deaths. It's important to note that men get breast cancer too.

Approximately one in 10 women with breast cancer have what is considered "hereditary breast cancer," which also means that for nine out of ten women there is no family history. What this means is that most people do not know they are at risk, and it is important to see your doctor right away if you notice an abnormality in your breasts. There are many myths about the causes of breast cancer, but the truth is that anyone could be at risk.

The treatment of breast cancer has improved in recent years. Many women are now able to have breast-conserving surgeries such as a lumpectomy, rather than the routine radical mastectomies of the past. Sentinel node biopsy procedures are also sparing many women the full axillary lymph node dissections of the past which can lead to swollen and painful arms—something called lymphedema. Advances in our understanding of the genetics of cancer now allow some people to determine if they may be at risk of developing breast cancer. While this area is still in its infancy and laden with emotion, it offers hope that it will lead to better early detection and possibly prevention in the future.

Unfortunately, breast cancer still spreads, and metastatic breast cancer is not yet curable. Women who are dealing with metastatic breast cancer may feel left out of the loop as they attend the many awareness events surrounded by women with early-stage breast cancer. During " Pinktober" we need to remember that we have a long way to go with this disease.

Prostate Cancer

Prostate cancer is the most common cancer in men. Just as heredity plays a role in breast cancer, people may have a genetic predisposition to prostate cancer as well. Some men have symptoms of prostate cancer such as urinary frequency, urgency, and hesitancy, but most men do not have any symptoms at the time of diagnosis.

There has been considerable controversy over PSA testing for prostate cancer. Part of the difficulty lies in knowing which cancers will grow and spread and which will never cause a problem. Newer tools for calculating risk are helping physicians better understand which of these cancers have the potential to spread (and need aggressive treatments) and which are better left alone.

The possible side effects of treatments, especially impotence and incontinence, make the diagnosis of this cancer even more frightening. Thankfully newer surgical techniques such as robotic surgery and other advances in treatment are lowering the risk that these side effects will occur.

Colorectal Cancer

Cancers of the colon and rectum are the 3rd most common cause of cancer-related deaths in both men and women. Thankfully, colon cancer screening has made a difference, and a significant factor in the recently noted decrease in cancer deaths overall is related to the prevention and early detection of colon cancer. 

Unlike screening tests for other types of cancer, screening colonoscopies play a role in both early detection and prevention. These studies allow physicians to find cancers in the earliest most treatable stages—what is known as early detection. But they can also be preventive. When precancerous polyps are found in the colon they may be removed before they ever have a chance to become cancers.

Pancreatic Cancer

Pancreatic cancer is not one of the leading cancers to be diagnosed, but it is the fourth leading cause of cancer-related deaths in men and the 5th most common in women. Due to its location and absence of symptoms in the early stages, pancreatic cancer is often diagnosed at a stage when surgery is no longer possible.

Risk factors for pancreatic cancer include smoking, Jewish ethnicity, and a history of pancreatitis among others. Pancreatic cancer may run in families as well and it's thought that at least 10 percent of these cancers are hereditary. The BRCA2 gene mutation most often associated with breast cancer, appears to increase the risk of pancreatic cancer as well. There is not a general screening tool for this cancer, but screening may be considered for those who have a significant family history.  Recently it's been found that periodontal disease (gum disease) raises the risk of this disease, making those dreaded visits to your dentist even more important.

A common late symptom is "painless jaundice"—a yellowish discoloration of the skin and the whites of the eyes without other symptoms. Unfortunately, this is usually a late symptom. Take a moment to familiarize yourself with the symptoms of pancreatic cancer

Though historically there has been few treatments available for people with advanced cancers of the pancreas, that is beginning to change, and newer and better treatments are on the horizon.

Leukemia

Leukemia is the most common cancer in children but occurs proportionally less often in adults. Relatively speaking, leukemia accounts for a much higher percentage of total cancers in children than in adults, but the total number of adults with leukemia in numerically higher. These cancers begin in the white blood cells which form along two different lines in the bone marrow. Leukemias which occur in the lymphoid cell line are termed lymphocytic (or lymphoblastic) leukemias, and those in the myeloid cell line, myelocytic or myelogenous leukemias. These abnormal white blood cells function poorly at fighting off bacteria and viruses, and as they build up in the bone marrow, can interfere with the normal production of other blood cells.

Leukemias are broken down into acute leukemias and chronic leukemias based on the maturity of the cells, with acute leukemias being cancer of very immature cells. Acute leukemias are usually very aggressive and fast growing, whereas chronic leukemias may grow slowly over a period of months to years. Eventually, most chronic leukemias transform into an acute, rapidly growing phase.

Treatment for some leukemias has made dramatic progress over the past years and decades. Whereas acute lymphocytic leukemia (ALL) was once almost always rapidly fatal, the majority of children with this cancer now achieve long-term survival with chemotherapy. Likewise, the addition of the targeted drug Gleevec (imatinib) has radically changed the prognosis for some people with chronic myelogenous leukemia (CML). Gleevec targets a genetic abnormality in these cancer cells which drive their growth.

Lymphoma

Lymphomas are broken own into two categories: Hodgkin's lymphoma and non-Hodgkin's lymphoma. These cancers begin in the type of white blood cell known as lymphocytes. Hodgkin's lymphomas are cancers of B lymphocytes, whereas non-Hodgkin's lymphoma is a group of over 60 diseases which may involve either B or T lymphocytes. 

There are several risk factors for lymphoma. Some lymphomas are linked with chemical exposures in the environment, while others appear in relation to viral infections. Some of these have a hereditary aspect as well.

Symptoms may include painless enlargement in lymph nodes anywhere in the body from the neck to the groin. Night sweats are a classic symptom of lymphomas and comprise one of the B symptoms of lymphoma.

The treatment of lymphomas, since there are so many different types which behave in different ways, varies tremendously. Many of these cancers are treated with chemotherapy and monoclonal antibodies, and high-dose chemotherapy followed by stem cell transplant may be used for advanced lymphomas. Some of these cancers, on the other hand, are very slow growing, and a period of watchful waiting during which the cancer is simply monitored may be recommended.

Melanoma

Melanoma is much less common than other forms of skin cancers such as squamous cell carcinoma and basal cell carcinoma but is responsible for the majority of skin cancer-related deaths. Around 10 percent of people have a family history of the disease and those who have fair complexions or many moles appear to be at greater risk. These cancers are much easier to treat in the early stages, but to be treated, they first need to be recognized.

It's important to see your doctor if you have any skin lesion which is concerning to you—no matter what it looks like. Everyone should memorize the ABCD mnemonic for symptoms of melanoma. These include A  for asymmetry, B for an irregular or notched border, C for color (melanomas often have more than one color) and D for diameter (melanomas are often larger than the size of a pencil eraser.)

The treatment and prognosis for melanomas is determined by the stage at which it is diagnosed. Surgery most often includes a wide excision of tissue in the surrounding area. While advanced stage melanomas have historically been extremely difficult to treat, recent studies with new immunotherapy drugs show great promise for at least some people with these advanced stages.

Bladder Cancer

Bladder cancer is more common in men that women, and more common in whites than in people of other ethnic backgrounds. Risk factors include smoking and exposure to occupational chemicals (especially dyes used in printing.) In some regions of the world, a parasitic infection is the most common cause. Most often, however, there are no obvious risk factors.

The symptoms of these cancers are also symptoms of many other conditions and can include blood in the urine, needing to urinate more often than usual, and discomfort with urinating. The survival rate is strongly influenced by the stage of the cancer at diagnosis, and anyone with unexplained blood in their urine or other urinary symptoms should consult their doctor.

Thyroid Cancer

Thyroid cancers are very common, but thankfully the majority of these tumors have very high survival rates as well. Most of these tumors are either papillary thyroid cancer, follicular thyroid cancer, or medullary thyroid cancer. An uncommon type of thyroid cancer called anaplastic thyroid cancer is the most serious of these cancers, and the hardest to treat.

Thyroid cancer is the most rapidly increasing cancer in the United States, though it's not known if this is a true increase or if it simply being detected more often through better imaging tests. It is more common in women than in men and often affects young and middle-aged women. Risk factors include a history of thyroid disease, radiation exposure to the neck, and iodine deficiency among others.

Endometrial (Uterine) Cancer

Endometrial cancer is a cancer of the lining of the uterus, and is most often discovered when a woman who is menopausal begins to bleed again, or when a premenopausal woman has irregular periods. Risk factors include not having had children, obesity, having received the breast cancer drug Tamoxifen, and some types of hormone replacement therapy. Long-term use of birth control pills, in contrast, appears to lower the risk.

The treatment for endometrial cancer is primarily surgery and is more effective the earlier the cancer is diagnosed. Women who have abnormal vaginal bleeding—even though this is common—should seek medical attention.

Kidney Cancer

There are a few different types of kidney cancer, with renal cell carcinoma being the most common. Risk factors may include smoking, some genetic syndromes, and some medications. When symptoms occur, they often include blood in the urine or back and flank pain.

Surgery is the treatment of choice for kidney cancer, though many of these cancers are found in the more advanced stages. Thankfully, many targeted drugs have been approved in recent years for kidney cancer, and other treatments such as immunotherapy offer promise as well.

Less Common Cancers

Less common cancers that still affect a significant number of people each year in the United States include:

  • Ovarian cancer - Ovarian cancer is one of the curable cancers when caught early, but is unfortunately often found in the advanced stages of the disease. It has been called the "silent killer" as symptoms such as bloating and vague abdominal pain may not appear until the tumor is quite large and has spread.
  • Testicular cancer - Testicular cancer is an example of a cancer in which treatments have made major advances. Whereas in the past these tumors were most often fatal, many of these tumors can now be cured, even those which have metastasized to other regions of the body. Just as women are encouraged to do self-breast exams, men are encouraged to do testicular self-exam s for lumps.
  • Brain tumors - Unlike other cancers, brain cancers do not often spread to other regions of the body. Due to their location, enclosed in the brain, these tumors most often cause damage by increasing pressure on other structures in the brain. Some of these cancers have a genetic link and environmental exposures are also implicated as a possible cause. Heavy cell phone use has been linked to the development of gliomas, the most common form of brain tumors.
  • Myeloma - Myeloma, also known as multiple myeloma, is a cancer of plasma cells. Plasma cells are B lymphocytes, the type of white blood cells which produce antibodies. Just as normal plasma cells produce antibodies, these cancerous plasma cells often produce antibodies, and the accumulation of these identical antibodies (a clone) may collect in the kidneys causing damage. The disease is often diagnosed when portions of these antibodies are found in a urine sample. Myeloma cells are often present in the blood and lymph nodes and may not form an actual tumor. They are treated similarly to other blood-related cancer such as lymphoma with chemotherapy, targeted therapies, and stem cell transplantation.

Uncommon and Rare Cancers

There are many types of uncommon and rare cancers, yet when you add these together they are actually fairly common. It can be frustrating if you have one of these cancers, especially if you hear of the large advocacy events for people with some other cancers such as breast cancer. Thankfully, the research being done to look for cures for the more common cancers often results in new treatments for less common cancers as well. Examples of some uncommon and rare cancers include:

Symptoms of Cancer

For most cancers, we do not yet have a screening test that can be used to find them in the earliest of stages; the stages at which they are most curable. What this means is that having an awareness of the most common symptoms of cancer, and talking to your doctor if you experience any of these, is critical in taking good care of your health

Common symptoms of cancer include:

Less common symptoms occur with many cancers but are no less important. Examples include jaundice, a yellowish discoloration of the skin, and even new onset depression. The important point is to talk to your doctor if you have any symptoms at all which are unexplained. And if those symptoms remained unexplained after you see your doctor, it's important to go back for another visit or get a second opinion. Many cancer survivors are alive due to being their own advocates and not settling for a diagnosis of "unexplained."

Cancer Treatments

The best treatments for cancer depend on the type and stage of the cancer and many other factors. We are also learning that every cancer is different on a molecular level. Two people with the exact same type and stage of cancer could have very different cancers which respond to treatments in very different ways. That said, treatments for cancer can be separated into 2 main categories.

  • Local treatments - Local treatments include surgery and radiation therapy. These treat a cancer where it began but are unable to reach cancer cells that may have traveled away from the primary cancer via the bloodstream or lymphatic system. When cancers are caught early, local treatments can often cure the cancer.
  • Systemic treatments - Systemic treatments include chemotherapy, targeted therapies, hormonal therapies, and immunotherapy, and treat cancer cells wherever they happen to be in the body. Systemic therapies are usually needed if a cancer has spread (or if there is a chance it has spread) and for blood-related cancers.

Cancer treatment options may include:

  • Surgery - For solid tumors, surgery often offers the best chance to cure a cancer.
  • Chemotherapy - Chemotherapy refers to the use of cytotoxic chemicals to kill cancer cells. Since these drugs kill any actively growing cells, not just cancer cells, treatment often includes the well-known side effects of hair loss and digestive symptoms.
  • Radiation therapy - Radiation therapy uses high-energy radiation to kill cancer cells. It may be used for several different purposes ranging from a goal to cure small cancers, to simply decreasing pain from cancers which have spread to bones.
  • Targeted therapies - Targeted therapies target cancer cells or processes important to cancer cells specifically, and may have fewer side effects than conventional chemotherapy.
  • Immunotherapy - Immunotherapy is an exciting new treatment approach to cancer, taking into account that our immune systems often know how to fight cancer. These treatments range from drugs which stimulate our immune systems to those which use the principles of our immune response to treat cancer.
  • Hormonal therapies - Also known as endocrine therapies, hormonal therapies are often used for breast cancer and prostate cancer. With some of these cancers, hormones produced naturally in the body can bind to and stimulate the growth of cancer cells. This stimulation by hormones may be prevented by decreasing the production of hormones in the body or by blocking the ability of the hormones to bind with and stimulate cancer cells to grow.
  • Stem cell transplant - Stem cell transplants may be used following high-dose chemotherapy or radiation therapy to replace the blood cells in the bone marrow.

How Does Family History Affect Cancer Risk?

With talk about "breast cancer genes" and companies now offering genetic testing for cancer risk, you may be wondering how important your family history is in determining your cancer risk.

We are only beginning to understand the genetics of cancer and know even less about how our genes affect our risk, but we have found that genetics can influence the risk of developing many cancers. For example, 10 percent of people with melanoma have a history of the disease. 

There are a few important take away points to consider. The first is that it is very important to take a careful family history. Write down the cancers people in your family have experienced, their age, and any other pertinent information. Make sure to include all cancers, even if it is a cancer type that's not usually thought of as "hereditary." Sometimes it is the combination of cancer types that is of more concern than any one type of cancer alone.

On the same note, don’t become discouraged if you appear to be at risk based on your family history. It's said that knowledge is power, and this is an example of when that saying can be clearly true. If you have a family history (a genetic risk) for cancer, you may wish to think of it this way:  Having a family history of a disease alerts you to be on the lookout for that disease. For example, if you have a family history of breast cancer you may be more likely to do self-breast exams, have mammograms, and see your doctor as soon as possible if you find a lump. Yet 90 percent of people who develop breast cancer do not have a family history. Those without a family history may be less likely to do self-exams, have regular screening, or to race to their doctor with an abnormal finding.

The bottom line is that we can't alter our genes, but having an idea about the blueprint on those genes may help you find a cancer in the earliest most treatable stages. To explore in greater depth what we are learning about genetics and cancer, check out the following article:

Cancer Survivorship

In the past, it came as a surprise when someone survived cancer, but now, more than half of people enjoy long-term survival after their initial diagnosis. There are an estimated 15 million cancer survivors in the United States alone, and that number is growing.

While we have come a long way in improving survival rates, we are only beginning to appreciate what has been coined "cancer survivorship." Treatments for cancer can be grueling, and a significant number of people have some ongoing symptoms related to treatment long after that treatment is done.

We've known for a long time that rehabilitation can be helpful for people who have a stroke or even a knee replacement, and the field of cancer rehabilitation (such as pulmonary rehabilitation for lung cancer survivors) is just beginning to meet the unmet needs of cancer survivors as well. Until this becomes widespread, people who have survived cancer may need to voice this need to their oncologists rather than the other way around. Initial studies suggest that rehabilitation—whether it is to restore physical function lost due to cancer, coping with the post-traumatic stress common to survivors, or to decrease the disability from lymphedema, rehabilitation can make a difference in the quality of life for people who have survived cancer.

As a final note in survivorship, many people who have survived cancer long for a chance to help others facing this disease. Whether you are newly diagnosed and looking for support, or have completed treatment and entered survivorship, there are many organizations through which you can receive or provide support for others. And as long as we are talking about advocacy, make sure to learn the ribbon colors for different cancers. keeping in mind that light purple is the color that stands for all cancers—and all survivors—standing together.

For Friends and Loved Ones

If you're learning about cancer because a loved one was diagnosed, thank you. The saying, "It takes a village" was never more accurate than in the setting of cancer. One of the hardest feelings as you support someone with cancer is the sense of helplessness. What can you do to make your loved one's journey a bit easier?

With so many things in life we imagine ourselves in a similar situation, trying to imagine what our needs would be. What is it really like to live with cancer? What we've learned is that the most important thing is your presence. Your presence more than anything else can bring comfort when the rest of life doesn't seem to be following the rules.

Check out these tips for supporting a loved one with cancer, but again, your presence, and taking the time to listen can be your greatest gift. And don't forget that while you are taking care of your loved one, you need to care for yourself. We know that is easier said than done, but it can make a big difference as time goes on. Cancer is a marathon, not a sprint.

A Word From Verywell

Cancer is a frightening disease and emotions can run deep if you hear this word in the same sentence as your name or that of a loved one. What are the first steps you should take, and what do you need to know?

By reading this information you are taking the first step to empower yourself, whether you have recently been diagnosed, have been living with the disease for some time, or simply wish to educate yourself about these diseases. One in two men and one in two women are expected to develop cancer during their lifetime, and those numbers do not include skin cancer. It may seem we are in the middle of an epidemic of cancer, but this is not a cause for despair. Treatments—and survival rates—for cancer are improving steadily, At the same time we are learning more about the causes, and what might be done to prevent cancer in the first place.

If you've been diagnosed with cancer, reach out to your loved ones. Don't try to go it alone. Learn to let others help you.  Ask a lot of questions and be your own advocate in your cancer treatment.

We still have a way to go in discovering better treatments for cancer, but research and advances are taking place every day. Hundreds of medications are currently being studied in clinical trials. And until we have a cure for cancer, keep in mind that amidst all of the challenges, cancer changes people in good ways too. Whether it is a new appreciation for life, more compassion for others, or a deeper sense of empathy, there are some silver linings for those who have to face this heartwrenching disease.

Sources:

National Cancer Institute. What is Cancer? Updated 02/09/15. http://www.cancer.gov/about-cancer/understanding/what-is-cancer

National Institute of Health. SEER Training Module. Cancer Classification. 2016. http://training.seer.cancer.gov/disease/categories/classification.html

World Health Organization. International Classification of Diseases for Oncology, 3rd Edition (ICD-0-3). Updated 10/05/15. http://www.who.int/classifications/icd/adaptations/oncology/en/

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