Rectal Cancer: Symptoms, Causes, Treatment

What are the symptoms of rectal cancer?

Rectal cancer, also known as colorectal cancer when it affects both the rectum and colon, can present with a variety of symptoms. Early symptoms may be subtle or mistaken for other conditions, which is why regular screening is important, especially for those at higher risk. Common symptoms include:

1. Change in Bowel Habits

• Diarrhea: Frequent, loose stools.
• Constipation: Difficulty passing stools or infrequent bowel movements.
• Change in Stool Consistency: Stools may become narrower or thinner.

2. Rectal Bleeding

• Blood in Stool: Bright red or dark-colored blood may be visible in the stool.
• Blood on Toilet Paper: Blood may appear on the tissue after wiping.

3. Abdominal Pain or Discomfort

• Cramping: Persistent or recurring abdominal muscle cramps.
• Pain: Discomfort or pain in the lower abdomen or rectal area.

4. Unexplained Weight Loss

• Weight Loss: Unintentional weight loss without a change in diet or exercise.

5. Feeling of Incomplete Bowel Evacuation

• Incomplete Emptying: A sensation that the bowel is not completely emptied after a bowel movement.

6. Presence of Mucus in Stool

• Mucus: Noticeable mucus in the stool or on toilet paper.

7. Pelvic Pain

• Discomfort: Pain in the pelvic region, which may be persistent.

8. Fatigue and Weakness

• General Fatigue: Feeling unusually tired or weak, which may be related to anemia caused by bleeding.

9. Anemia Symptoms

• Paleness: Pale skin or feeling unusually tired, which can be related to chronic blood loss.

10. Tenesmus

• Urgency: A feeling of needing to have a bowel movement even after the bowels are empty.

11. Unexplained Bloating

• Swelling: Abdominal bloating or feeling of fullness.

When to Seek Medical Attention

• Persistent Symptoms: If you experience any of these symptoms persistently or if symptoms worsen.
• Screening: Regular screening is recommended, especially for individuals over the age of 45 or those with a family history of colorectal cancer or other risk factors.

What are the causes of rectal cancer?

Rectal cancer, like other forms of colorectal cancer, arises from a combination of genetic, environmental, and lifestyle factors. While the exact cause is not always known, several risk factors are associated with an increased likelihood of developing rectal cancer:

1. Genetic and Familial Factors

• Inherited Syndromes: Conditions like Lynch syndrome (hereditary non-polyposis colorectal cancer) and familial adenomatous polyposis (FAP) significantly increase the risk.
• Family History: A family history of colorectal cancer or polyps can elevate risk, even in the absence of a known genetic syndrome.

2. Age

• Older Age: The risk of rectal cancer increases with age, particularly after age 50.

3. Personal Medical History

• Previous Colorectal Cancer: Having had colorectal cancer or polyps in the past increases the risk of developing rectal cancer.
• Inflammatory Bowel Diseases: Conditions like ulcerative colitis or Crohn’s disease increase the risk due to chronic inflammation.

4. Lifestyle Factors

• Diet: Diets high in red and processed meats and low in fruits, vegetables, and fiber are linked to a higher risk of rectal cancer.
• Physical Inactivity: Lack of exercise can contribute to increased cancer risk.
• Obesity: Excess body weight is associated with a higher risk of developing rectal cancer.

5. Smoking and Alcohol Use

• Smoking: Tobacco use is a known risk factor for many cancers, including rectal cancer.
• Alcohol: Excessive alcohol consumption is linked to an increased risk of rectal cancer.

6. Sex

• Gender: Men are slightly more likely to develop rectal cancer compared to women, though both genders are at risk.

7. Sexual Orientation and Behavior

• High-Risk Behaviors: Certain high-risk sexual behaviors may increase the risk of HPV infection, which is associated with an increased risk of anal and rectal cancers. Anal sex is an indicator for rectal cancer.

8. Other Factors

• Diabetes: Some studies suggest that diabetes and insulin resistance may be linked to an increased risk of colorectal cancer.
• Radiation Therapy: Prior radiation treatment for other cancers, especially in the pelvic area, may increase risk.

Preventive Measures

• Screening: Regular screening starting at age 45, or earlier if you have risk factors, can help detect precancerous polyps or early-stage cancer.
• Healthy Lifestyle: Eating a balanced diet rich in fruits, vegetables, and fiber, maintaining a healthy weight, and engaging in regular physical activity can reduce risk.
• Avoiding Tobacco and Limiting Alcohol: Quitting smoking and limiting alcohol intake can lower the risk.

If you have concerns about rectal cancer or are at increased risk due to personal or family history, discussing preventive measures and screening options with a healthcare provider is essential. Early detection and lifestyle modifications can significantly impact outcomes.

How is the diagnosis of rectal cancer made?

Diagnosing rectal cancer involves a combination of medical history, physical examination, and various diagnostic tests. Here is a comprehensive approach to the diagnosis of rectal cancer:

1. Medical History and Symptoms Review

• Patient History: Discuss any symptoms such as rectal bleeding, changes in bowel habits, abdominal pain, or weight loss.
• Family History: Review family history of colorectal cancer or genetic conditions associated with increased risk.

2. Physical Examination

• Digital Rectal Exam (DRE): A physical examination where a doctor inserts a gloved, lubricated finger into the rectum to check for lumps or abnormalities.

3. Diagnostic Tests

Endoscopic Procedures

• Colonoscopy:
• Procedure: A flexible tube with a camera (colonoscope) is inserted through the rectum to visualize the entire colon and rectum.
• Purpose: Allows for direct visualization of the rectum and colon, and biopsy samples can be taken if abnormalities are found.
• Sigmoidoscopy:
• Procedure: Similar to a colonoscopy but only examines the lower part of the colon and rectum.
• Purpose: May be used if the tumor is suspected to be located in the rectum.
• Endorectal Ultrasound:
• Procedure: An ultrasound probe is inserted into the rectum to provide images of the rectal wall and surrounding tissues.
• Purpose: Helps assess the depth of tumor invasion and whether cancer has spread to nearby tissues.

Imaging Tests

• CT Scan (Computed Tomography):
• Procedure: Uses X-rays and computer technology to create detailed images of the abdomen and pelvis.
• Purpose: To check for any spread of cancer to other organs or lymph nodes.
• MRI (Magnetic Resonance Imaging):
• Procedure: Uses magnetic fields and radio waves to create detailed images of the rectum and surrounding tissues.
• Purpose: Helps evaluate the extent of the tumor, especially if surgery is being considered.
• PET Scan (Positron Emission Tomography):
• Procedure: A radioactive tracer is injected, and imaging detects areas of high metabolic activity.
• Purpose: To identify cancer that may have spread to other parts of the body.

4. Biopsy

• Procedure: A sample of tissue from the rectum is taken during a colonoscopy, sigmoidoscopy, or endoscopic procedure.
• Purpose: The tissue is examined under a microscope to confirm the presence of cancer cells and determine the type of cancer.

5. Laboratory Tests

• Blood Tests:
• Complete Blood Count (CBC): To check for anemia or signs of infection.
• Liver Function Tests: To assess liver health, as cancer can spread to the liver.
• Tumor Markers: Such as carcinoembryonic antigen (CEA) levels, which may be elevated in colorectal cancer.

6. Staging

Once rectal cancer is confirmed, staging is performed to determine the extent of the disease. This helps guide treatment decisions and can include:

• Staging System: The TNM system (Tumor, Node, Metastasis) is commonly used to describe the extent of the primary tumor, involvement of lymph nodes, and presence of metastases.
• Additional Imaging: Further imaging may be used to determine the stage of the cancer and plan treatment.

Summary

The diagnosis of rectal cancer involves a combination of clinical evaluation, endoscopic examination, imaging studies, and tissue biopsy. If you experience symptoms suggestive of rectal cancer or have a family history of colorectal cancer, discussing your concerns with a healthcare provider and undergoing appropriate diagnostic tests is crucial for early detection and effective management.

What is the treatment for rectal cancer?

Treatment for rectal cancer depends on various factors, including the stage of the cancer, the location and size of the tumor, the patient’s overall health, and personal preferences. The primary treatment options for rectal cancer are surgery, radiation therapy, chemotherapy, and targeted therapies. Here’s an overview of each approach:

1. Surgery

• Local Excision: For very early-stage cancers, the tumor and a small margin of healthy tissue can be removed through a minor procedure, often during a colonoscopy.
• Polypectomy: Removal of cancerous polyps during a colonoscopy, applicable if the cancer is detected early and is localized.
• Resection:
• Low Anterior Resection (LAR): Removal of the rectum and surrounding tissue while preserving the anus. The colon is then reattached to the remaining part of the rectum or a stoma is created.
• Abdominoperineal Resection (APR): Removal of the rectum and anus, creating a permanent colostomy. This approach is used if the cancer is very close to the anus or involves the anal sphincters.
• Total Mesorectal Excision (TME): A type of resection that involves removing the rectum along with the surrounding mesorectum, which is crucial for reducing the risk of recurrence.

2. Radiation Therapy

• Preoperative Radiation (Neoadjuvant Therapy): Radiation therapy given before surgery to shrink the tumor, making it easier to remove and reducing the risk of cancer recurrence. Often combined with chemotherapy.
• Postoperative Radiation (Adjuvant Therapy): Radiation therapy given after surgery to target any remaining cancer cells and reduce the risk of recurrence.
• Palliative Radiation: Used to alleviate symptoms in advanced cases where the cancer cannot be completely removed.

3. Chemotherapy

• Adjuvant Chemotherapy: Administered after surgery to kill any remaining cancer cells and reduce the risk of recurrence. It is often used in combination with radiation therapy.
• Neoadjuvant Chemotherapy: Given before surgery to shrink the tumor and improve surgical outcomes. Used in combination with radiation therapy for some patients.
• Palliative Chemotherapy: Used to manage symptoms and control cancer growth in cases where surgery is not possible.

4. Targeted Therapy

• Targeted Drugs: These drugs specifically target cancer cells with certain genetic mutations or proteins involved in tumor growth. Examples include bevacizumab (Avastin) and cetuximab (Erbitux).
• Molecular Testing: Testing the cancer cells for specific genetic mutations can help determine if targeted therapies are appropriate.

5. Immunotherapy

• Immune Checkpoint Inhibitors: Drugs that help the immune system recognize and attack cancer cells. They may be used in specific cases, such as for tumors with high microsatellite instability (MSI-H).

6. Supportive and Palliative Care

• Pain Management: Ensuring effective management of pain and other symptoms.
• Nutritional Support: Addressing dietary needs and managing side effects related to treatment.
• Psychosocial Support: Providing counseling and support to help with emotional and psychological aspects of cancer treatment.

7. Follow-Up and Surveillance

• Regular Check-ups: Includes physical exams, colonoscopies, imaging tests, and blood tests to monitor for any signs of recurrence or new cancer.
• Long-Term Monitoring: Continued surveillance to detect any late effects of treatment and to ensure ongoing health and recovery.

Summary

The treatment plan for rectal cancer is tailored to each individual based on the specific characteristics of the cancer and the patient’s overall health. A multidisciplinary team, including oncologists, surgeons, radiation therapists, and other specialists, will work together to develop and implement the most effective treatment strategy. If you have rectal cancer or are at risk, discussing your options with your healthcare provider is essential for determining the best approach for your situation.

What is the survival rate for rectal cancer?

The survival rate for rectal cancer depends on several factors, including the stage of the cancer at diagnosis, overall health, and how well the cancer responds to treatment. The survival rates are typically measured by the 5-year relative survival rate, which compares the survival of people with rectal cancer to those without it.

Here are the general survival rates based on stages:

• Localized (Stage I): When the cancer is confined to the rectum, the 5-year survival rate is approximately 90%.
• Regional (Stage II and some Stage III): If the cancer has spread to nearby tissues or lymph nodes, the 5-year survival rate is around 71%.
• Distant (Stage IV): When the cancer has spread to distant parts of the body (such as the liver or lungs), the 5-year survival rate drops to approximately 16%.

These rates are general estimates, and individual outcomes can vary based on factors like treatment advancements and patient-specific circumstances. Early detection significantly improves the chances of survival.