An ESCP Guide for Patients
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What is rectal cancer?
Rectal cancer is a disease that starts in the rectum - the last part of your large intestine, where stool is stored before it leaves your body.
It often begins as small, non-cancerous growths called polyps, which can turn into cancer over time.
Rectal cancer is part of a broader group called colorectal cancer, which includes cancers of both the colon and rectum.
Risk factors for rectal cancer
While the exact cause of rectal cancer isn’t fully known, certain factors can increase your risk:
- Age: most people diagnosed are over 50, but younger adults can also be affected
- Diet: eating a lot of red or processed meat and not enough fibre may raise your risk
- Family history: if close relatives have had rectal or colon cancer, your risk may be higher
- Lifestyle: smoking, being overweight, drinking too much alcohol, and not getting enough exercise can all play a role
- Medical conditions: long-term conditions like Crohn’s disease or ulcerative colitis may increase your risk
Some factors, such as lifestyle and diet, you can change:
Symptoms of rectal cancer
Rectal cancer may not show symptoms in its early stages, but as it progresses, you may experience:
- Changes in bowel habits: diarrhoea, constipation or thinner stools lasting several days
- Feeling of incomplete bowel emptying: a sensation that you still need to pass stool even after going
- Blood in stool or rectal bleeding: blood may appear bright red or dark
- Abdominal pain or discomfort: cramps, bloating, or persistent pain
- Unexplained weight loss: losing weight without trying
- Weakness or fatigue: due to anemia (low red blood cell count), a possible result from chronic blood loss from the tumour
- Lump in the rectal area: occasionally, a noticeable mass may be present
How is rectal cancer diagnosed?
Doctors use several tests to diagnose rectal cancer:
- Faecal occult blood test (FOBT): a stool sample is tested for hidden blood. This non-invasive test detects hidden (occult) blood in the stool, which might be a sign of cancer or polyps. A small stool sample is tested for traces of blood not visible to the eye.
- Colonoscopy: a colonoscopy is the most reliable way to check for rectal cancer. It allows doctors to look directly inside your colon and rectum using a small camera. If something unusual is found, it can often be removed or tested right away - sometimes preventing cancer before it starts.
- Colonoscopy is the gold standard for diagnosing rectal cancer because it allows direct visualisation and immediate tissue sampling. The importance of timely colonoscopy cannot be overstated, as early detection is extremely important and polyp removal might render further treatment unnecessary.
- Biopsy: a small tissue sample is taken for microscopic analysis to confirm cancer
- Imaging tests:
- CT scan: is mainly used to check if the cancer has spread to other organs
- MRI: provides detailed images of the tumour and surrounding tissue
- Endorectal ultrasound (ERUS): this test uses sound waves to create images of the inside of your rectum. It helps doctors see how deep the tumour goes and whether it has spread
- Blood tests: these check for anaemia and may include a tumour marker test (CEA test)
Stages of rectal cancer
Rectal cancer is classified into stages:
- Stage 0 (in situ): cancer is situated only in the inner lining of the rectum
- Stage I: cancer has spread into the rectal wall but hasn’t reached lymph nodes
- Stage II: cancer has grown through the rectal wall but not to lymph nodes
- Stage III: cancer has spread to nearby lymph nodes but not distant organs
- Stage IV: the cancer has spread to other parts of the body, such as the liver or lungs. While this stage is more challenging to treat, there are therapies that can help manage symptoms and improve quality of life
Treatment options for rectal cancer
Your treatment plan depends on the stage of the cancer, your overall health, and your preferences. A team of specialists - including surgeons, oncologists, and radiologists - will work with you to find the best approach. You’ll be involved in every decision.
Surgery
Surgery is the main treatment for rectal cancer.
- Local excision: small, early-stage tumours may be removed through the rectum.
- Rectal resection: larger tumours may require removal of part of the rectum and nearby lymph nodes. Rectal resection is a surgery to remove part or all of the rectum where the cancer is located. the main goal is to take out the tumour and nearby tissues to help prevent the cancer from coming back.
There are different types of rectal resection, depending on the location and size of the tumour:
- Low anterior resection (LAR): this is done when the cancer is in the upper or middle part of the rectum. The surgeon removes the affected portion of the rectum and reconnects the remaining bowel to the colon (this connection is called an anastomosis). In many cases, normal bowel function can return over time.
- Abdominoperineal Resection (APR): this is needed if the cancer is very low in the rectum, near the anus. In this case, the rectum and anus are removed, and it is not possible to reconnect the bowel. The patient will need a permanent stoma (an opening in the abdomen where waste exits the body into a bag).
- Proctectomy with coloanal anastomosis: when cancer is low, but it is still possible to preserve the anus, the rectum is removed, and the colon is connected directly to the anus. Sometimes a temporary stoma is created to protect the new connection while it heals.
What is a stoma?
A stoma is a surgically created opening in the abdomen that allows stool to leave the body. Depending on the type of surgery and how your body heals, this may be:
- Temporary: often used to allow the bowel to heal after surgery. It may be reversed after a few months
- Permanent: needed if reconnection is not possible, especially in APR surgery
Immunotherapy or targeted therapy
In some cases of advanced rectal cancer, doctors may use targeted therapy or immunotherapy to help fight the disease.
Targeted therapy uses special drugs that focus on specific changes or weaknesses in cancer cells. Unlike regular chemotherapy, it tries to attack only the cancer cells while doing less harm to healthy ones. It’s often used when:
- The cancer has spread (metastatic)
- The cancer has certain gene changes (like KRAS or BRAF mutations)
Immunotherapy helps your own immune system recognise and attack cancer cells. Some cancers 'hide' from the immune system - this treatment helps unmask them. It may be used in patients with a specific gene condition called MSI-high or dMMR (your doctor may test for this first).
These treatments don’t work for everyone, but for some people they can help slow the cancer down or shrink tumours, especially when other treatments haven’t worked.
If you're a candidate for these treatments, your cancer team will explain the risks, benefits, and whether they're right for you.
Other therapies
In addition to surgery, other treatments may be used to help control rectal cancer, either before or after the surgery. These treatments aim to shrink the tumour, reduce the chance of it coming back, or treat cancer that has spread.
Radiation therapy
Radiation uses high-energy rays (like X-rays) to kill cancer cells or shrink tumours. It is often used before surgery to make the tumour easier to remove, or after surgery to destroy any remaining cancer cells.
Chemotherapy
Chemotherapy uses special cancer-fighting drugs to slow or stop cancer growth. It may be given:
- Before surgery to shrink the tumour
- After surgery to reduce the risk of cancer coming back
- If the cancer has spread, as a main treatment to control it
Total neoadjuvant therapy
In some cases, both chemotherapy and radiation are given before surgery. This is called total neoadjuvant therapy. It can help shrink the tumour more effectively and improve surgery results. In a few cases, if the tumour disappears completely with this treatment, surgery might not be needed at all. Your doctors will carefully monitor your response with scans and exams to decide the best next step.
After treatment: what happens next?
After treatment, regular follow-up is important to monitor your recovery and check for any signs of cancer returning. This may include:
- Blood tests and imaging scans
- Colonoscopies at scheduled intervals
- Ongoing support from your care team
- Follow-up usually continues for at least five years
Functional changes after rectal cancer surgery
After rectal cancer surgery, some patients may experience changes in how their bowels, bladder, or sexual organs work. This is because the rectum plays an important role in storing and controlling stool, and surgery can affect nearby nerves and tissues.
A common condition after surgery is called low anterior resection syndrome (LARS). It can cause:
- Frequent or urgent need to go to the toilet
- Difficulty controlling bowel movements (incontinence)
- Passing small amounts of stool multiple times
- A feeling of incomplete emptying
Other possible changes may include:
- Urinary problems: such as difficulty emptying the bladder or needing to urinate more often
- Sexual problems: including changes in sensation, erection difficulties (in men), or discomfort during sex (in women)
These issues can affect your quality of life, but you don’t have to face them alone. Many treatments and support options are available to help improve your symptoms. If you are experiencing any of these problems, please speak with your doctor or care team.
Prognosis
The outlook for rectal cancer depends on the stage at diagnosis:
- Early-stage cancer (Stage 1 or 2): high survival rates with treatment
- Stage 3: can often be cured with aggressive treatment
- Stage 4: the cancer has spread to other parts of the body, such as the liver or lungs. While this stage is more challenging to treat and generally not curable, there are therapies that can help manage symptoms and improve quality of life.
Although it is a harsh diagnosis, many people with rectal cancer go on to live full, active lives.
Prevention tips
While not all cases can be avoided, there’s a lot you can do to lower your risk - starting today. Small, consistent changes can make a big difference over time.
- Regular screening: colonoscopies and stool tests can detect cancer early and even prevent it by removing polyps. Each country has a different screening programme, ask your doctor for more information on when and why you should be screened.
- Healthy diet: choose foods that support a healthy digestive system:
- Whole grains (like oats, brown rice)
- Fruits and vegetables (aim for color and variety)
- Legumes and nuts
- Try to limit red and processed meats like bacon, sausages, and deli meats.
- Stay active: regular exercise helps reduce cancer risk.
- Avoid smoking and excess alcohol: smoking and heavy drinking are linked to a higher risk of rectal cancer. Quitting or cutting back is one of the best things you can do for your overall health.
Important note
This guide is meant to help you understand rectal cancer better. For advice that’s right for your situation, please talk to your doctor or healthcare team.
If you have concerns about rectal cancer, do not hesitate to consult a healthcare provider for personalised guidance.
Disclaimer
The information provided here is general and hopes to correctly inform the patient to the extent possible. However, this document cannot discuss all aspects of a specific condition or procedure, or of the individual patient.
The decision on which procedure will give you the best result is made by your doctor or colorectal surgeon during consultation and based on shared and informed decision-making with the patient.