Cancer

Cancer is a group of diseases where cells grow out of control. These abnormal cells multiply quickly and can invade and harm healthy tissues in the body. This spread is a key feature of many cancers.

Cancer is a major global health problem, ranking as the second most common cause of death. However, the chances of surviving cancer are getting better. This is because of advancements in finding cancer early (screening), treating it, and helping people avoid getting it in the first place (prevention).

Cancer can cause different symptoms, depending on where it grows in the body. While these signs aren't only linked to cancer, they can be warning signals:

• Feeling very tired all the time (fatigue): This is a common symptom, but it can have many causes.

• A lump or thickening under the skin: A new, persistent lump or a noticeable change in an existing one should be checked by a doctor.

• Changes in weight: Losing or gaining weight without trying to can be a sign of something wrong.

• Skin changes: Look out for yellowing, darkening, redness, sores that won't heal, or changes in moles. These changes could be a sign of a problem.

• Changes in bathroom habits: If you notice ongoing changes in how often you have bowel movements or how you urinate, talk to your doctor.

• Ongoing cough or breathing problems: If you're coughing a lot or having trouble breathing, it's important to see a doctor.

• Trouble swallowing: Difficulty swallowing food or liquids can be a sign of a medical issue.

• Changes in your voice (hoarseness): If your voice sounds different or is hoarse for a while, it could be related to something more serious.

• Digestive problems: Persistent indigestion, discomfort after eating, or other ongoing issues with digestion could warrant a doctor's visit.

• Ongoing pain: If you have unexplained muscle or joint pain that lasts, it's worth getting checked out.

• Fever or night sweats: Unexplained fevers or sweating a lot at night can be a sign that something isn't right.

• Bleeding or bruising: If you're bleeding or getting bruises easily, it's important to see a doctor.

If you experience any of these symptoms for a while, schedule an appointment with your doctor. Even if you don't have noticeable symptoms but are worried about your risk of cancer, it's still a good idea to talk to your doctor. They can discuss which screenings might be right for you.

See your doctor if you're worried about something.

If you don't have any noticeable problems but are concerned about your cancer risk, talk to your doctor. Ask them what cancer screenings and tests might be a good idea for you.

Cancer happens when the instructions inside our cells get messed up. Imagine a cell's DNA as a set of detailed instructions, telling it what to do – how to function, grow, and divide. These instructions are organized into genes. Errors, or mutations, in these genes can lead to problems.

These mutations can cause a cell to act strangely:

• Rapid growth: A mutated gene might tell a cell to grow and divide much faster than usual. This creates many new cells, all with the same faulty instructions.

• Uncontrolled growth: Normal cells know when to stop growing, ensuring the right number of each type of cell exists. Cancer cells lose the ability to control their growth – the genes that normally tell them to stop dividing (called tumor suppressor genes) are faulty. This leads to uncontrolled growth.

• DNA repair mistakes: Our cells have special genes that fix errors in their DNA. If these repair genes are mutated, errors aren't corrected, increasing the chance of a cell becoming cancerous. These are frequent causes of cancer. However, many other gene mutations can contribute.

Where do these mutations come from?

Mutations can happen for different reasons:

• Inherited mutations: Sometimes, a person is born with a genetic mutation passed down from their parents. These mutations are a factor in some cancers, but not many.

• Acquired mutations: Most mutations happen after birth. Several things can cause them:

  • Exposure to harmful substances: Smoking, radiation, viruses, certain chemicals (carcinogens), and even obesity can cause mutations.
  • Other factors: Hormones, chronic inflammation, and a lack of exercise can also increase the risk.
  • Normal cell growth: Mutations happen frequently during normal cell growth, but usually, the cell's own mechanisms recognize and fix them. Occasionally, a mistake isn't caught, leading to a cancerous cell.

How do mutations cause cancer?

The mutations you inherit and those you acquire throughout your life can work together to cause cancer. Having an inherited mutation doesn't guarantee you'll get cancer. It often means you need one or more additional mutations to trigger the disease. The inherited mutation might make you more susceptible to cancer if you're exposed to certain risk factors.

Exactly how many mutations are needed for cancer to develop is still not fully understood and likely varies depending on the type of cancer.

Many cancers happen to people without any obvious reasons. Doctors do know some things that can increase your chances of getting cancer, though.

Cancer often takes a long time to develop. This is why most people who get cancer are 65 or older. While older adults are more likely to get cancer, it can happen at any age.

Certain choices we make can raise our cancer risk. For example, smoking, drinking too much alcohol (more than one drink a day for women and two for men), too much sun exposure (especially severe sunburns), being overweight or obese, and having unprotected sex can all contribute to a higher risk.

You can make changes to your lifestyle to lower your risk of cancer. While some lifestyle changes might be easier than others.

Only a small number of cancers are caused by inherited genes. If cancer runs in your family, it's possible that harmful gene changes are passed down. If you're concerned about your family history, you could talk to your doctor about genetic testing to see if you have these inherited changes that might increase your cancer risk. Even if you have these changes, it doesn't mean you will definitely get cancer.

Some ongoing health problems, like ulcerative colitis (a type of inflammatory bowel disease), can significantly increase your risk of certain cancers. It's a good idea to discuss your risks with your doctor.

The world around us might contain dangerous chemicals that increase cancer risk. Even if you don't smoke, you could be exposed to secondhand smoke if you're around smokers or live with someone who smokes. Chemicals found in homes or workplaces, such as asbestos and benzene, are also linked to a higher cancer risk.

Cancer and its Treatments: Common Side Effects and Complications

Cancer and its treatments can lead to various side effects and complications. Understanding these is crucial for managing them effectively.

Pain: Cancer itself, or the treatments used to fight it, can cause pain. Not all cancers are painful, but pain is a common issue. Fortunately, medications and other therapies can often relieve cancer-related pain.

Fatigue: Many things can cause fatigue in people with cancer. Treatment like chemotherapy or radiation therapy frequently leads to temporary fatigue. Strategies can be implemented to manage this common side effect.

Breathing Difficulties: Cancer or its treatment can make it hard to breathe. Medical interventions can often help alleviate this problem.

Nausea: Some types of cancer and cancer treatments can cause nausea. Doctors can sometimes predict if a particular treatment might cause nausea, allowing for preventative measures. Medications and other strategies are often available to help manage nausea.

Bowel Problems (Diarrhea or Constipation): Cancer and its treatments can disrupt the normal functioning of the digestive system, leading to diarrhea or constipation.

Weight Loss: Cancer can disrupt the body's ability to use food effectively. This can lead to unintentional weight loss, often regardless of diet or calorie intake. While nutritional support through feeding tubes may seem helpful, it often doesn't significantly impact weight loss in these cases.

Chemical Imbalances: Cancer can upset the body's chemical balance, increasing the risk of other problems. Symptoms of these imbalances may include excessive thirst, frequent urination, constipation, or confusion. These imbalances require medical attention.

Brain and Nervous System Issues: Cancer can press on nerves, causing pain and loss of function in a part of the body. Brain cancer can lead to headaches and stroke-like symptoms, such as weakness on one side of the body.

Immune System Reactions: Sometimes, the body's immune system reacts to cancer by attacking healthy cells. These rare reactions, called paraneoplastic syndromes, can cause various symptoms, like difficulty walking or seizures.

Cancer Spread (Metastasis): As cancer progresses, it can spread to other parts of the body. The places it spreads to depend on the type of cancer.

Cancer Recurrence: Even after successful treatment, some cancers have a risk of returning. Some types of cancer are more prone to recurrence than others. Talking to your doctor about ways to minimize this risk is important. A follow-up care plan, including regular checkups and scans, is often recommended to monitor for recurrence.

Doctors have found ways to lower your chances of getting cancer. Here are some important steps you can take:

1. Quit Smoking: If you smoke, quitting is crucial. Smoking isn't just linked to lung cancer; it increases your risk of many other cancers. Stopping now will significantly reduce your future cancer risk. If you don't smoke, don't start.

2. Protect Yourself from the Sun: The sun's harmful ultraviolet (UV) rays can cause skin cancer. To reduce your risk, limit your time in the sun, especially during peak hours. Seek shade, wear protective clothing, and use sunscreen with a high SPF.

3. Fuel Your Body Right: Eating healthy foods is key to overall health, including cancer prevention. Focus on plenty of fruits and vegetables, whole grains, and lean proteins. Limit processed meats. A balanced diet provides your body with the nutrients it needs to fight off disease.

4. Move Your Body Regularly: Regular physical activity can help lower your cancer risk. Aim for at least 30 minutes of moderate-intensity exercise most days of the week. If you aren't used to exercising, start slowly and gradually increase the time and intensity of your workouts.

5. Maintain a Healthy Weight: Being overweight or obese can increase your risk of several types of cancer. A healthy weight is achieved and maintained through a combination of a healthy diet and regular exercise. Talk to your doctor about a healthy weight range for you.

6. Drink Alcohol Responsibly (If at All): If you choose to drink alcohol, do so in moderation. For healthy adults, this means no more than one drink a day for women and no more than two drinks a day for men. One drink is typically a 5-ounce glass of wine, a 12-ounce beer, or a 1.5-ounce shot of liquor.

7. Get Screened Regularly: Talk to your doctor about which cancer screenings are right for you. The right screenings depend on your age, family history, and other risk factors. Regular screenings can help detect cancer early, when it's most treatable.

8. Consider Immunizations: Some viruses can raise your cancer risk. Certain immunizations can help protect you from these viruses. For example, vaccines can prevent hepatitis B (which can lead to liver cancer) and human papillomavirus (HPV) (which can lead to cervical cancer and other cancers). Talk to your doctor about whether these immunizations are right for you.

Early Cancer Detection: A Guide for Patients

Catching cancer early is often the best chance for a cure. Talk to your doctor about which cancer screenings might be right for you.

Some cancers are helped by screening tests that can find the disease early, potentially saving lives. For other cancers, screenings are only recommended for people at higher risk.

Many medical groups and patient support organizations provide guidelines for cancer screening. Review these guidelines with your doctor, and together you can decide the best screening plan based on your individual risk factors.

Doctors use several methods to diagnose cancer:

• Physical Exam: Your doctor checks your body for lumps or other signs of cancer, like changes in skin color or a swollen organ. They might feel different parts of your body for unusual bumps.

• Lab Tests: Blood and urine tests can help your doctor look for problems that might be linked to cancer. For example, a complete blood count (CBC) can reveal unusual white blood cell numbers or types in someone with leukemia.

• Imaging Tests: These tests let doctors see inside your body without surgery. They can use X-rays, CT scans, MRIs, ultrasounds, and PET scans to look for signs of cancer in your bones and organs.

• Biopsy: A biopsy is when a doctor takes a small tissue sample to check under a microscope. This is often the only way to be certain if cancer is present. The type of biopsy depends on where the cancer is and what kind of cancer it is.

Under the microscope, normal cells look uniform—all about the same size and shape. Cancer cells, on the other hand, look different, with varying sizes and a disorganized appearance.

Staging Cancer:

Once cancer is diagnosed, doctors need to figure out how far it has spread (the stage). Knowing the stage helps them decide on the best treatment options and predict the chances of a cure.

To determine the stage, doctors might use imaging tests like X-rays or bone scans to see if the cancer has spread to other parts of the body.

Cancer stages are usually numbered 0 through 4 (sometimes written as Roman numerals 0 through IV). Higher numbers mean the cancer is more advanced. Some cancers use different ways to describe the stage, such as using letters or words instead of numbers.