Rectal Cancer: Symptoms, Causes and Stages

Rectal Cancer may not be a comfortable subject for many, but it’s one that deserves our immediate attention. This type of cancer may start quietly, in the form of a small, harmless polyp, but if left unchecked, it may become a serious health issue. Having said that, the good news is, by understanding the different types, recognising the warning signs, and exploring treatment options, you can take control of your health. Although it's a daunting topic, knowing what to look out for and what steps to take can make all the difference. Without further ado, let’s understand the essentials and empower ourselves with the knowledge required to face this challenge head-on.

What is Rectal Cancer?

Rectal Cancer is a type of cancer that starts in the rectum, which is the last part of the large intestine leading to the anus. It occurs when cells in the rectum begin to grow uncontrollably, forming a tumour. This uncontrolled growth can invade nearby tissues and spread to other parts of the body. The cancer often begins as small, non-cancerous growths called polyps that can eventually turn cancerous.

How is Rectal Cancer Staged?

Rectal Cancer is staged to determine the extent of the disease and guide treatment options. The staging process involves assessing the size of the tumour, how deeply it has invaded the rectal wall, and whether it has spread to nearby lymph nodes or distant organs. The most commonly used staging system is the TNM system, which breaks down as follows:

• T (Tumour): This describes the size and extent of the primary tumour. It’s classified from T1 (tumour invades only the inner layer of the rectum) to T4 (tumour has spread through the rectal wall to nearby structures).
• N (Nodes): This indicates whether the cancer has spread to nearby lymph nodes. It ranges from N0 (no regional lymph node involvement) to N2 (cancer has spread to several lymph nodes).
• M (Metastasis): This shows whether the cancer has spread to distant parts of the body. M0 means no distant metastasis, while M1 indicates that the cancer has spread to distant organs or tissues.

Combining these categories helps determine the overall stage, from Stage 0 (carcinoma in situ, where cancer is only in the lining) to Stage IV (advanced cancer that has spread to distant parts of the body). This staging helps doctors plan the most effective treatment and predict outcomes.

What are the Symptoms of Rectal Cancer?

Symptoms of Rectal Cancer can vary, but common signs include:

• Blood in Stool: Noticeable red or dark blood in your stool or on toilet paper.
• Change in Bowel Habits: Persistent diarrhoea, constipation, or a feeling of incomplete bowel emptying.
• Abdominal Pain: Cramping, discomfort, or pain in the lower abdomen.
• Unexplained Weight Loss: Losing weight without trying or without a clear reason.
• Narrowing of Stool: Stool that appears thinner than usual.
• Rectal Bleeding: Bleeding from the rectum or experiencing rectal pain.
• Persistent Urgency: A frequent feeling of needing to have a bowel movement, even if you’ve just gone.
• Feeling of Fullness: A sense of fullness or pressure in the rectal area.

Note: These symptoms can also be caused by other conditions, so it’s important to consult a healthcare professional for an accurate diagnosis if you experience any of these signs.

What Causes Rectal Cancer?

The exact cause of Rectal Cancer is not fully understood, but several factors are known to increase the risk. These include:

• Genetic Factors: Inherited genetic mutations, such as those in the genes associated with familial adenomatous polyposis (FAP) or Lynch syndrome, can increase the risk of Rectal Cancer.
• Age: The risk of developing Rectal Cancer increases with age, particularly after the age of 50.
• Family History: Having a family history of Rectal Cancer or other colorectal Cancers can increase your risk.
• Diet and Lifestyle: A diet high in red or processed meats and low in fruits, vegetables, and whole grains may contribute to the risk. Smoking and excessive alcohol consumption are also associated with a higher risk.
• Inflammatory Bowel Diseases: Conditions like ulcerative colitis or Crohn's disease increase the risk of Rectal Cancer.
• Personal History: A history of polyps in the colon or rectum can increase the risk, as these can sometimes become cancerous over time.
• Sedentary Lifestyle: Lack of physical activity is linked to an increased risk of colorectal Cancers, including Rectal Cancer.

Note: While these factors can increase the risk, having one or more risk factors does not necessarily mean the person will develop Rectal Cancer. Moreover, regular screenings and a healthy lifestyle can help manage and reduce risks.

How does Rectal Cancer Spread?

Rectal Cancer can spread through several mechanisms:

• Local Spread: The cancer can grow directly into surrounding tissues and organs, such as the bladder, prostate, or vagina.
• Lymphatic Spread: Cancer cells can travel to nearby lymph nodes through the lymphatic system. The presence of cancer in these lymph nodes can indicate a more advanced stage of the disease.
• Hematogenous Spread: Cancer cells can enter the bloodstream and spread to distant organs, such as the liver or lungs. This type of spread is often referred to as metastatic Rectal Cancer.
• Peritoneal Spread: The cancer can spread to the peritoneum, the lining of the abdominal cavity, leading to peritoneal carcinomatosis.

How is Rectal Cancer Diagnosed?

Rectal Cancer is diagnosed through a combination of medical history, physical exams, and various diagnostic tests:

Medical History and Physical Exam

The doctor will ask about symptoms, family history, and lifestyle factors. A physical exam, including a digital rectal exam (DRE), may be performed to check for abnormalities in the rectum.

Colonoscopy

A flexible tube with a camera (colonoscope) is inserted into the rectum and colon to examine the inner lining. Biopsies (tissue samples) can be taken during the procedure for further analysis.

Imaging Tests

• CT Scan: Provides detailed images of the abdomen and pelvis to check for the spread of cancer.
• MRI pelvis: It provides detailed local staging and tumour extent assessment in carcinoma rectum, evaluating lymph nodes, mesorectal fascia, and detecting local recurrence.
• PET CT: It complements MRI by detecting distant metastases, guiding radiotherapy planning, and monitoring treatment response, offering whole-body imaging for comprehensive evaluation in carcinoma rectum.
• Ultrasound: Endorectal ultrasound can help evaluate the depth of the tumour and its relation to nearby structures. It is particularly useful in very early lesions.

Biopsy

Tissue samples obtained during a colonoscopy or surgery are examined under a microscope to confirm the presence of cancer and determine its type and grade.

Blood Tests

While not definitive for diagnosis, blood tests such as a complete blood count (CBC) or liver function tests can help assess overall health and detect any issues related to cancer spread.

Blood tumour markers:

• CEA (Carcinoembryonic Antigen) is the most commonly used marker, useful for:
• Monitoring response to therapy
• Detecting recurrence (elevated levels suggest potential relapse)
• Prognostication (pre-treatment levels correlate with survival)

What are the Treatment Options by Stage?

Treatment options for Rectal Cancer vary depending on the stage of the disease. Here’s a general overview:

Stage 0 (Carcinoma in Situ)

• Local Excision: Removal of the cancerous area from the rectal wall, often done during a colonoscopy.
• Endoscopic Mucosal Resection (EMR)/ Endoscopic submucosal dissection(ESD) : A technique where the tumour is removed through the colonoscope if it's very early and superficial.
• TAMIS : Trans-anal minimally invasive surgery is performed in patients when ESD is not a suitable option for a large vicious adenoma due to its size or its location.

Stage I: Early-Stage Rectal Cancer (T1-2 N0 M0)

Surgery is the main treatment in this stage. Usually surgery is preferred as an upfront treatment option.

Types of Surgery

• Transanal endoscopic microsurgery (TEM)
• Total mesorectal excision (TME) which involves complete or partial removal of rectum with its surrounding fat cover and lymph nodes. This procedure is done by minimal invasive surgery mainly with the help of robotics or laparoscopy.
• Adjuvant Therapy: In some cases, especially if there’s a risk of recurrence, additional treatments like chemotherapy or radiation may be considered.

Role of Robotic Rectal Cancer Surgery

Minimally invasive surgery using a robotic system to remove Rectal Cancer while preserving surrounding nerves and tissues. 

Benefits

• Improved accuracy and precision
• Enhanced visualisation
• Reduced blood loss and scarring
• Faster recovery
• Less pain
• Better preservation of bowel and bladder function 

Radical Surgery

• Total Mesorectal Excision (TME) with robotic assistance
• Removal of cancerous rectum and surrounding tissues
• Lymph node dissection

Autonomic Nerve Preservation

• Preservation of pelvic nerves controlling bladder and sexual function
• Reduced risk of urinary and sexual dysfunction
• Improved quality of life

Robotic Techniques

• Da Vinci Xi or X system
• High-definition 3D visualisation
• Precise dissection and suturing 

Indications

• Early-stage Rectal Cancer
• Locally advanced Rectal Cancer
• Recurrent Rectal Cancer

Potential Benefits for Patients

• Improved oncological outcomes
• Enhanced quality of life
• Reduced complications
• Faster return to normal activities

Stage II: Localised Rectal Cancer (T3-4 N0 M0)

• Surgery: The primary treatment is usually a partial or total resection of the rectum, often involving the removal of surrounding tissues and possibly nearby lymph nodes.
• Radiation Therapy: Sometimes used before surgery to shrink the tumour or after surgery to kill any remaining cancer cells.
• Chemotherapy: May be used, particularly if there’s a high risk of recurrence.

Hence in stage II, the Usual Treatment Protocol Is:

Neoadjuvant chemoradiation (CRT) involves chemotherapy along with local radiation therapy to the rectum followed by Surgery followed by adjuvant chemotherapy after surgery. 

Stage III: Locally Advanced Rectal Cancer (T1-4,N1-2, M0 )

 In this stage, the treatment of Rectal Cancer is more challenging. Surgery remains the main treatment option in these cases however it is not usually opted as an upfront procedure.

The multidisciplinary team which comprises of a medical oncologist, Radiation oncologist, GI Surgeon, Radiologist and Supportive care team will create a tailored plan considering:

• Cancer stage and location
• Tumor biology (e.g., KRAS, NRAS, BRAF mutations)
• Overall health and medical history
• Lifestyle and preferences
• Genetic testing (e.g., MMR, MSI)

In this stage, the newer approaches are Total neoadjuvant therapy (TNT) and Immunotherapy.

What is TNT?

Total Neoadjuvant Therapy (TNT) is a treatment approach for locally advanced Rectal Cancer. It combines chemotherapy and radiation therapy before surgery. 

Why TNT?

• Improved Treatment Outcomes: TNT has shown better tumour response rates, increased chances of complete surgical removal, and reduced risk of recurrence.
• Increased Organ Preservation: TNT may allow for sphincter-sparing surgery, preserving bowel function and quality of life.
• Enhanced Chemotherapy Effectiveness: Giving chemotherapy before surgery makes cancer cells more sensitive to treatment.
• Better Tumor Shrinkage: Radiation therapy helps shrink the tumour, making surgery more effective.
• Reduced Complications: TNT may lower surgical complication rates.

Benefits for Patients

• Improved Survival Rates: TNT has shown improved overall survival and disease-free survival.
• Less Invasive Surgery: TNT may enable less extensive surgery, reducing recovery time.
• Preservation of Bowel Function: TNT aims to preserve sphincter function, maintaining normal bowel habits.
• Enhanced Quality of Life: TNT helps minimise treatment-related side effects.
• Immunotherapy: It's also one of the newer options for certain subgroups of Rectal Cancer patients particularly those who are MSI-high.

Ongoing trials explore:

• Combination regimens (e.g., pembrolizumab + chemotherapy)
• Neoadjuvant immunotherapy
• Adjuvant immunotherapy

Potential Biomarkers for immunotherapy in carcinoma rectum are:

• MSI-H status
• Tumor Mutational Burden (TMB)
• PD-L1 expression
• Mismatch Repair (MMR) deficiency 

Stage IV: Metastatic Rectal Cancer (Tany, Nany, M1)

Surgery plays a crucial role in managing certain patients of Stage 4 Rectal Cancer, aiming to:

• Control symptoms
• Improve the quality of life
• Prolong survival

Surgical Options

• Debulking surgery: Removing bulk of tumor
• Metastasectomy: Removing isolated metastases
• Palliative procedures: Relieving symptoms (e.g., bowel obstruction)

Liver Metastatectomy:

• Removes liver metastases
• Improves survival (5-year survival rate: 20-50%)
• Considered for:
• Limited liver metastases
• Good liver function

Lung Metastatectomy

• Removes lung metastases
• Improves survival (5-year survival rate: 30-60%)
• Considered for:
• Limited lung metastases
• Good lung function

Peritoneal Metastasis Treatment:

• HIPEC (Hyperthermic Intraperitoneal Chemotherapy):
• Heated chemotherapy directly applied to abdominal cavity
• Improves survival (5-year survival rate: 30-50%)

• PIPAC (Pressurised Intraperitoneal Aerosol Chemotherapy):
• Aerosolized chemotherapy delivered to abdominal cavity
• Emerging treatment option

Multidisciplinary Approach:

Surgery is often combined with:

• Chemotherapy
• Radiation therapy
• Immunotherapy
• Palliative care to manage symptoms
• Targeted therapy (e.g., bevacizumab, cetuximab)

What are the complications of Rectal Cancer?

Rectal Cancer can lead to several complications, both from the cancer itself and from its treatment. These include:

• Bowel Obstruction: As the tumour grows, it can block the rectum or colon, causing severe abdominal pain, nausea, vomiting, and difficulty passing stool.
• Metastasis: Cancer cells can spread to distant organs, such as the liver or lungs, leading to additional health issues and making treatment more complex.
• Local Recurrence: The cancer may return in the rectum or nearby tissues after treatment, requiring further intervention.
• Incontinence: Surgery, especially involving the rectum and surrounding structures, can lead to difficulties with bowel control, resulting in incontinence or leakage.
• Sexual Dysfunction: Depending on the extent and location of the surgery, patients may experience sexual dysfunction or changes in sexual function.
• Lymphedema: Removal of lymph nodes during surgery can lead to swelling in the legs or pelvis due to fluid build-up.
• Wound Complications: Surgical wounds may become infected or heal poorly, leading to complications like abscesses or dehiscence (wound reopening).
• Adverse Effects of Treatment: Chemotherapy and radiation therapy can cause side effects such as fatigue, nausea, diarrhoea, and skin irritation. Long-term side effects may include bowel issues or changes in bowel habits.
• Psychological Impact: The diagnosis and treatment of Rectal Cancer can lead to emotional and psychological challenges, including anxiety, depression, and changes in body image.
• Managing these complications often involves a multidisciplinary approach, including surgery, medical treatment, and supportive care to improve quality of life and overall outcomes.

Can Rectal Cancer be prevented?

While it's not possible to completely prevent Rectal Cancer, several strategies can significantly reduce your risk:

• Regular Screening: Early detection through screening tests such as colonoscopy can catch cancer or precancerous polyps early. Screening is generally recommended starting at age 45 for those at average risk, or earlier for those with higher risk factors.
• Healthy Diet: Eating a diet rich in fruits, vegetables, whole grains, and low in red and processed meats can lower the risk of Rectal Cancer. High-fibre diets and balanced nutrition are beneficial.
• Regular Exercise: Engaging in regular physical activity helps maintain a healthy weight and reduces the risk of developing colorectal Cancers.
• Avoiding Tobacco and Limiting Alcohol: Smoking and excessive alcohol consumption are linked to a higher risk of Rectal Cancer. Quitting smoking and limiting alcohol intake can lower your risk.
• Maintaining a Healthy Weight: Being overweight or obese increases the risk of Rectal Cancer. Achieving and maintaining a healthy weight through diet and exercise can be preventive.
• Managing Inflammatory Bowel Disease: If you have conditions like ulcerative colitis or Crohn’s disease, managing these conditions effectively with the help of your healthcare provider can reduce your risk of developing Rectal Cancer.
• Genetic Testing and Preventive Surgery: For individuals with hereditary conditions like familial adenomatous polyposis (FAP) or Lynch syndrome, genetic testing and preventive measures, such as prophylactic surgery or more frequent screening, may be recommended.
• Regular Medical Check-ups: Regular visits to your healthcare provider can help monitor and manage any risk factors or early signs of Rectal Cancer.

By adopting these preventive measures, you can significantly reduce your risk and improve your overall health. 

Wrap Up

Questions to Ask Your Doctor 

• What stage is my Rectal Cancer?
• What treatment options are recommended?
• What are the benefits and risks of each treatment?
• How will treatment affect my daily life?
• What support services are available? 

While Rectal Cancer presents serious challenges, proactive measures and early detection can make a substantial difference. By staying informed about risk factors, symptoms, and screening options, you empower yourself to take control of your health. At Max Hospitals, we are dedicated to providing comprehensive care and advanced treatment options tailored to each patient’s needs. If you have concerns or are due for a screening, we encourage you to reach out to our experienced team. Take the first step towards a healthier future today by scheduling a consultation with a specialist at Max Hospitals.