Rectal cancer is a type of cancer that originates in the rectum, which is the last several inches of the large intestine before the anus. This cancer develops when the cells in the rectal lining grow uncontrollably and form tumors. It is a serious condition that can be life-threatening if not diagnosed and treated early.
Rectal cancer often begins as a polyp, which is a small growth on the inner lining of the rectum. Some of these polyps can turn cancerous over time. The cancerous cells can invade nearby tissues and organs and may also spread (metastasize) to distant parts of the body, including the liver and lungs.
Common but treatable – Rectal cancer is one of the most common gastrointestinal cancers but can be effectively treated if detected early.
Develops from polyps – Most rectal cancers begin as benign polyps that gradually become malignant.
Often associated with lifestyle factors – Diet, obesity, and smoking play significant roles in increasing the risk.
Screening is crucial – Early detection through colonoscopy can prevent cancer progression.
The exact cause of rectal cancer is not always known, but several risk factors contribute to its development.
Age – Most cases occur in individuals over 50, but younger people can also develop the disease.
Family history – A family history of colorectal cancer or polyps increases the risk.
Inflammatory bowel disease (IBD) – Conditions like Crohn’s disease or ulcerative colitis heighten the risk.
Diet – A diet high in red and processed meats and low in fiber is linked to a higher risk.
Obesity – Being overweight or obese increases the likelihood of developing rectal cancer.
Smoking and alcohol consumption – Both habits can contribute to cancer formation.
Genetic mutations – Conditions like Lynch syndrome or familial adenomatous polyposis (FAP) raise the risk of rectal cancer.
Rectal cancer symptoms often resemble those of other digestive disorders, making early detection difficult.
Changes in bowel habits – Persistent diarrhea, constipation, or narrowing of stools.
Rectal bleeding – Blood in the stool or rectal bleeding.
Abdominal pain – Cramping, bloating, or persistent discomfort.
Unexplained weight loss – Losing weight without a known reason.
Fatigue and weakness – Generalized tiredness due to anemia from blood loss.
Incomplete bowel movements – A sensation of not fully emptying the bowels.
Rectal cancer is categorized based on the type of cells involved.
Adenocarcinoma (Most Common)
Accounts for over 95% of cases.
Develops in the mucus-producing glandular cells.
Mucinous Adenocarcinoma
Comprises about 10% of rectal cancers.
Produces excess mucus, which can make treatment challenging.
Signet Ring Cell Carcinoma
A rare and aggressive form of rectal cancer.
More likely to spread before detection.
Squamous Cell Carcinoma
Develops in the rectal lining.
Requires different treatment than adenocarcinoma.
Rectal cancer is diagnosed through a combination of physical examinations, imaging studies, and laboratory tests.
Colonoscopy – A flexible tube with a camera examines the rectum and detects polyps or tumors.
Biopsy – A sample of tissue is taken during a colonoscopy to confirm cancer.
CT scan or MRI – Advanced imaging helps determine tumor size and spread.
Blood tests – Tests for tumor markers such as carcinoembryonic antigen (CEA).
Endorectal ultrasound – Assesses tumor depth and lymph node involvement.
PET scan – Detects metastasis to distant organs.
The treatment approach depends on the cancer stage, overall health, and patient preferences.
Local excision – Removes early-stage tumors without affecting surrounding tissues.
Low anterior resection (LAR) – Removes part of the rectum while preserving normal bowel function.
Abdominoperineal resection (APR) – Removes the rectum and anus, requiring a permanent colostomy.
Used before surgery (neoadjuvant therapy) to shrink tumors.
May be combined with chemotherapy (chemoradiation).
Helps reduce recurrence risk post-surgery.
Administered before or after surgery to kill cancer cells.
Common drugs: 5-FU (fluorouracil), capecitabine, oxaliplatin.
Used for advanced or metastatic rectal cancer.
Targets specific molecules that promote cancer growth.
Includes drugs like bevacizumab (Avastin) and cetuximab (Erbitux).
Boosts the immune system to fight cancer cells.
Used in cases with genetic mutations like MSI-H or dMMR.
Survival rates for rectal cancer depend on early detection and treatment effectiveness.
Localized (confined to the rectum) – 5-year survival rate of about 90%.
Regional spread (nearby lymph nodes) – 5-year survival rate of around 71%.
Distant metastasis (spread to other organs) – 5-year survival rate drops to about 14%.
Tumor stage – Earlier detection leads to better outcomes.
Lymph node involvement – More affected nodes lower survival rates.
Tumor genetics – Certain mutations respond better to targeted therapies.
Overall health – Patients with good general health recover better.
Treatment response – Effectiveness of chemotherapy, radiation, or surgery.
While rectal cancer cannot always be prevented, certain measures can reduce the risk.
Regular screenings – Colonoscopies help detect and remove polyps early.
Healthy eating – A diet rich in vegetables, fruits, and fiber lowers risk.
Maintain a healthy weight – Obesity is linked to higher cancer risk.
Quit smoking and limit alcohol – Reduces cancer risk significantly.
Stay active – Exercise lowers the likelihood of developing rectal cancer.
Coping with rectal cancer requires lifestyle modifications and emotional support.
Follow-up care – Regular check-ups and screenings.
Healthy diet – High-fiber, low-fat diet for digestive health.
Pain management – Medications and therapies for symptom relief.
Emotional support – Support groups and counseling for mental well-being.
Physical activity – Regular exercise improves recovery and energy levels.