What is Rectal Cancer? Symptoms, Causes, & Treatment

Rectal cancer develops when cells in the rectum grow out of control and form tumors. The rectum is the final 6 inches of your large intestine, connecting your colon to your anus.

This type of cancer often starts slowly as small growths called polyps on the rectal wall. While many polyps remain harmless, some can gradually change into cancer over several years. The good news is that rectal cancer is highly treatable when caught early, and many people go on to live full, healthy lives after treatment.

What are the symptoms of rectal cancer?

Early rectal cancer may not cause any noticeable symptoms, which is why regular screening is so important. When symptoms do appear, they often develop gradually and can sometimes be mistaken for other common conditions.

Here are the symptoms you might experience, and remember that having these symptoms doesn't necessarily mean you have cancer:

• Changes in bowel habits that last more than a few days, like persistent diarrhea or constipation
• Blood in your stool, which might appear bright red or dark and tarry
• Rectal bleeding that's separate from bowel movements
• Persistent cramping, gas, or pain in your abdomen
• Feeling like your bowel doesn't empty completely after a movement
• Unexplained weight loss without trying to lose weight
• Fatigue or weakness that doesn't improve with rest
• Narrow stools that are thinner than usual

Some people also experience less common symptoms like pelvic pain, especially during bowel movements, or a constant feeling of needing to have a bowel movement even when the rectum is empty. These symptoms can significantly impact your daily comfort and quality of life.

If you notice any of these changes lasting more than a couple of weeks, it's worth having a conversation with your doctor. Many of these symptoms can be caused by less serious conditions, but getting them checked gives you peace of mind and ensures early treatment if needed.

What causes rectal cancer?

Rectal cancer happens when normal cells in the rectum develop genetic changes that cause them to grow uncontrollably. While we don't know exactly why this occurs in some people and not others, researchers have identified several factors that can increase your risk.

The development usually follows this pattern: healthy rectal cells pick up damage to their DNA over time, which can come from various sources like aging, lifestyle factors, or inherited genetic changes. When enough damage accumulates, cells start growing and dividing abnormally, eventually forming tumors.

Most cases develop from a combination of factors rather than a single cause. Age plays a significant role, as about 90% of cases occur in people over 50. Your family history matters too, especially if close relatives have had colorectal cancer or certain genetic conditions.

Environmental and lifestyle factors can also contribute to DNA damage in rectal cells. These include things like diet, physical activity levels, smoking, and alcohol consumption, which we'll explore more in the risk factors section.

What are the risk factors for rectal cancer?

Understanding your risk factors can help you make informed decisions about screening and lifestyle choices. Some factors you can't change, while others are within your control to modify.

Here are factors that may increase your risk, starting with the most significant ones:

• Age over 50, with risk continuing to increase as you get older
• Personal history of colorectal cancer or certain types of polyps
• Family history of colorectal cancer, especially in parents or siblings
• Inherited genetic syndromes like Lynch syndrome or familial adenomatous polyposis
• Inflammatory bowel diseases like Crohn's disease or ulcerative colitis
• Diet high in red meat and processed meats
• Low-fiber diet with few fruits and vegetables
• Sedentary lifestyle with little physical activity
• Smoking tobacco products
• Heavy alcohol consumption over many years
• Obesity, particularly excess weight around the midsection
• Type 2 diabetes

Less common risk factors include having received radiation therapy to the abdomen or pelvis for other cancers, and certain occupational exposures to chemicals. Some studies also suggest that people who work night shifts for many years may have slightly higher risk, though this connection is still being researched.

Having one or more risk factors doesn't mean you'll definitely develop rectal cancer. Many people with risk factors never get the disease, while others with no known risk factors do. The key is being aware of your personal risk profile so you can work with your doctor on appropriate screening and prevention strategies.

When to see a doctor for rectal cancer symptoms?

You should contact your doctor if you experience any persistent changes in your bowel habits or notice blood in your stool. While these symptoms often have benign causes, it's always better to get them evaluated promptly.

Seek medical attention within a few days if you have rectal bleeding, especially if it's accompanied by other symptoms like abdominal pain or changes in stool consistency. Even small amounts of blood shouldn't be ignored, as early-stage rectal cancer can cause minimal bleeding that's easy to dismiss.

Schedule an appointment soon if you're experiencing persistent abdominal discomfort, unexplained weight loss, or ongoing fatigue that doesn't improve with rest. These symptoms warrant evaluation even if they seem mild, as early detection significantly improves treatment outcomes.

If you're over 45 or have risk factors like family history, discuss screening options with your doctor even if you don't have symptoms. Regular screening can catch problems before they cause noticeable symptoms, when treatment is most effective.

What are the possible complications of rectal cancer?

Rectal cancer can lead to several complications, both from the cancer itself and sometimes from treatment. Understanding these possibilities helps you know what to watch for and when to seek additional medical care.

The most immediate complications often relate to the tumor's location and size:

• Bowel obstruction, where the tumor blocks the passage of stool
• Severe bleeding that can lead to anemia and weakness
• Perforation of the rectal wall, which can cause serious infection
• Spread to nearby organs like the bladder, prostate, or reproductive organs
• Metastasis to distant organs, most commonly the liver and lungs

Advanced rectal cancer can also cause complications related to its spread throughout the body. These might include liver problems if cancer spreads there, breathing difficulties if it reaches the lungs, or bone pain if it affects the skeleton. Some people may develop blood clots due to the cancer's effects on blood clotting systems.

Treatment-related complications can include surgical risks like infection or bleeding, side effects from chemotherapy such as nausea or neuropathy, and radiation therapy effects like skin irritation or bowel changes. However, your medical team will work closely with you to prevent and manage these issues.

The good news is that many complications can be prevented or effectively managed with proper medical care. Early detection and treatment significantly reduce the risk of serious complications developing.

How is rectal cancer diagnosed?

Diagnosing rectal cancer typically involves several steps, starting with a discussion of your symptoms and medical history. Your doctor will want to understand your specific symptoms, family history, and any risk factors you might have.

The physical examination usually includes a digital rectal exam, where your doctor gently inserts a gloved finger into your rectum to feel for abnormal growths or areas of concern. While this might feel uncomfortable, it's brief and provides important information about the lower part of your rectum.

If initial findings suggest further investigation is needed, your doctor will likely recommend additional tests:

• Colonoscopy, which allows direct visualization of the entire colon and rectum
• Flexible sigmoidoscopy, focusing on the lower portion of the colon and rectum
• CT scan of the abdomen and pelvis to check for tumor spread
• MRI of the pelvis for detailed images of the rectal area
• Blood tests including CEA (carcinoembryonic antigen) levels
• Biopsy to confirm the diagnosis and determine cancer type

If cancer is confirmed, additional staging tests might include PET scans, chest X-rays, or specialized MRI sequences to determine exactly how far the cancer has spread. This information is crucial for planning the most effective treatment approach.

The entire diagnostic process usually takes a few weeks to complete. While waiting for results can feel anxious, remember that thorough testing ensures you get the most accurate diagnosis and appropriate treatment plan.

What is the treatment for rectal cancer?

Rectal cancer treatment depends on several factors including the cancer's stage, location, and your overall health. The goal is always to remove the cancer completely while preserving as much normal function as possible.

For early-stage rectal cancer, treatment might involve surgery alone. Small tumors that haven't spread deeply into the rectal wall can sometimes be removed through minimally invasive procedures that preserve the rectum and normal bowel function.

More advanced cases typically require a combination approach:

• Neoadjuvant therapy (chemotherapy and radiation before surgery) to shrink the tumor
• Surgical removal of the tumor and surrounding tissue
• Adjuvant chemotherapy after surgery to eliminate any remaining cancer cells
• Targeted therapies for specific genetic mutations
• Immunotherapy for certain types of rectal cancer

Surgical options range from local excision for very early cancers to more extensive procedures like low anterior resection or abdominoperineal resection for larger tumors. Your surgeon will discuss which approach is best for your specific situation, including whether a temporary or permanent colostomy might be necessary.

Radiation therapy is often used in rectal cancer treatment, either before surgery to shrink tumors or after surgery to reduce recurrence risk. Modern radiation techniques are much more precise than in the past, reducing side effects while maintaining effectiveness.

Your treatment team will work with you to create a personalized plan that balances cancer cure with quality of life considerations. Many people with rectal cancer go on to live normal, active lives after treatment.

How to manage symptoms at home during rectal cancer treatment?

Managing symptoms and side effects at home plays an important role in your overall treatment experience. Working closely with your healthcare team while taking care of yourself at home can help you feel more comfortable and maintain your strength during treatment.

For digestive symptoms, eating smaller, more frequent meals often helps reduce nausea and makes it easier for your body to absorb nutrients. Focus on bland, easy-to-digest foods when you're not feeling well, and stay hydrated by sipping water or clear broths throughout the day.

Here are some practical strategies that many people find helpful:

• Keep a symptom diary to track what helps and what doesn't
• Use a sitz bath for comfort if you have rectal irritation
• Apply gentle, unscented moisturizers to skin affected by radiation
• Rest when you need to, but try to stay as active as possible
• Practice relaxation techniques like deep breathing or meditation
• Ask family and friends for help with daily tasks when needed

Fatigue is common during treatment, so listen to your body and rest when needed. Light exercise like short walks can actually help boost your energy levels and improve your mood, but always check with your doctor before starting any exercise program.

Don't hesitate to contact your healthcare team if symptoms become severe or if you develop new concerns. They can often suggest additional strategies or adjust your treatment plan to help you feel more comfortable.

How can rectal cancer be prevented?

While you can't prevent all cases of rectal cancer, you can significantly reduce your risk through lifestyle choices and regular screening. The most effective prevention strategy combines healthy living with appropriate medical screening based on your age and risk factors.

Regular screening is your most powerful tool for prevention. Colonoscopy can detect and remove precancerous polyps before they become cancer, effectively preventing the disease from developing. Most people should begin screening at age 45, or earlier if they have risk factors.

Lifestyle modifications that can help reduce your risk include:

• Eating a diet rich in fruits, vegetables, and whole grains
• Limiting red meat and avoiding processed meats
• Maintaining a healthy weight through balanced eating and regular exercise
• Exercising regularly, aiming for at least 150 minutes of moderate activity weekly
• Avoiding tobacco products completely
• Limiting alcohol consumption to no more than one drink per day for women, two for men
• Managing diabetes effectively if you have it

Some studies suggest that certain supplements like calcium and vitamin D might have protective effects, but it's best to get these nutrients from food sources when possible. Always discuss supplements with your doctor before starting them.

If you have inflammatory bowel disease, work closely with your gastroenterologist to manage your condition effectively. Well-controlled IBD may reduce your cancer risk compared to poorly managed disease.

How should you prepare for your doctor appointment?

Preparing for your appointment helps ensure you get the most from your time with the doctor and that all your concerns are addressed. Taking a few minutes to organize your thoughts beforehand can make the visit more productive and less stressful.

Write down all your symptoms, including when they started, how often they occur, and what makes them better or worse. Be specific about changes in your bowel habits, any bleeding you've noticed, and how your symptoms are affecting your daily life.

Bring important information with you:

• List of all medications, supplements, and vitamins you take
• Family history of cancer, especially colorectal cancer
• Your personal medical history, including any previous polyps or bowel problems
• Insurance cards and identification
• A trusted friend or family member for support if desired

Prepare questions to ask your doctor, such as what tests you might need, what the results could mean, and what treatment options are available. Don't worry about asking too many questions - your doctor wants to help you understand your situation completely.

If you're anxious about the appointment, that's completely normal. Consider bringing a notebook to write down important information, as it can be hard to remember everything discussed when you're feeling worried.

What's the key takeaway about rectal cancer?

The most important thing to remember about rectal cancer is that early detection saves lives. When caught early, rectal cancer is highly treatable, with many people going on to live full, healthy lives after treatment.

Don't ignore persistent changes in your bowel habits or other concerning symptoms. While these symptoms often have benign causes, getting them evaluated promptly ensures that if cancer is present, it can be treated as early as possible when treatment is most effective.

Regular screening is your best defense against rectal cancer. If you're 45 or older, or if you have risk factors like family history, talk to your doctor about screening options. Screening can prevent cancer by finding and removing precancerous polyps before they become malignant.

Remember that having risk factors doesn't mean you'll definitely develop rectal cancer, and many aspects of your risk are within your control through healthy lifestyle choices. Focus on what you can control while staying current with recommended screenings.