Colorectal cancer (CRC) is a type of cancer that starts in the colon or rectum, which are parts of the digestive system. It usually begins as small growths called polyps that can develop into cancer over time. Early detection through screenings can prevent colorectal cancer from progressing.
Colorectal cancer develops when abnormal cells grow uncontrollably in the colon or rectum, forming tumors. Over time, cancerous cells can invade nearby tissues and spread to other parts of the body.
Affects the colon and rectum – The lower parts of the digestive tract.
Develops from polyps – Some types of polyps may turn into cancer.
Early detection improves survival – Screening tests like colonoscopy help in early diagnosis.
Can spread if untreated – May reach the liver, lungs, and lymph nodes.
Preventable with lifestyle changes and screenings – A healthy diet and routine check-ups can reduce risk.
Colorectal cancer is caused by genetic and environmental factors.
Age – More common in people over 50.
Family history – A close relative with colorectal cancer increases risk.
Genetic mutations – Conditions like Lynch syndrome and familial adenomatous polyposis (FAP) raise risk.
Diet – High consumption of processed meats, red meat, and low-fiber foods.
Smoking and alcohol – Long-term use increases susceptibility.
Obesity and sedentary lifestyle – Lack of physical activity contributes to higher risk.
Inflammatory bowel diseases – Ulcerative colitis and Crohn’s disease can lead to cancer.
Early-stage colorectal cancer may not cause noticeable symptoms. As it progresses, the following signs may appear:
Changes in bowel habits – Persistent diarrhea, constipation, or narrow stools.
Blood in stool – Bright red or dark stools may indicate bleeding in the colon.
Unexplained weight loss – Losing weight without diet changes.
Abdominal pain or cramps – Persistent discomfort, bloating, or gas.
Fatigue and weakness – Due to blood loss or nutritional deficiencies.
Iron-deficiency anemia – Common in cases of chronic internal bleeding.
Colorectal cancer is categorized based on cell type and location.
The most common type (over 95% of cases).
Originates in the mucus-producing cells lining the colon and rectum.
Rare and develop in the connective tissues of the digestive tract.
Can be benign or malignant.
Cancer that starts in the immune cells of the digestive tract.
Slow-growing tumors that develop in the hormone-producing cells of the colon or rectum.
Several tests help in diagnosing colorectal cancer at different stages.
Colonoscopy – A thin tube with a camera inspects the colon and rectum.
Fecal Occult Blood Test (FOBT) – Detects hidden blood in stool.
CT Colonography (Virtual Colonoscopy) – A non-invasive imaging test.
Biopsy – A sample of abnormal tissue is analyzed under a microscope.
Imaging Tests (CT, MRI, PET scans) – Determines cancer spread.
Treatment depends on cancer stage, location, and overall health of the patient.
Polypectomy – Removal of small polyps during a colonoscopy.
Colectomy – Removal of part or all of the colon affected by cancer.
Lymph node dissection – To check for cancer spread.
Uses high-energy rays to destroy cancer cells.
Often used before or after surgery to shrink tumors.
Drug treatment that targets rapidly growing cancer cells.
Used in advanced cases to shrink tumors and prevent spread.
Focuses on specific molecules that promote cancer growth.
Drugs like cetuximab and bevacizumab block these pathways.
Helps the immune system recognize and attack cancer cells.
Effective in cases with genetic mutations (MSI-high or dMMR tumors).
Survival rates depend on early detection and response to treatment.
Localized cancer (early stage) – Over 90% five-year survival rate.
Regional spread (nearby tissues/lymph nodes) – About 70% survival rate.
Distant spread (metastatic cancer) – Drops to 14%.
Routine screenings improve survival – Early detection dramatically increases treatment success.
Cancer stage at diagnosis – Earlier detection leads to better outcomes.
Age and overall health – Younger and healthier patients respond better.
Treatment response – Some tumors are more resistant to treatment.
Access to healthcare – Regular screenings and prompt treatment improve survival rates.
Colorectal cancer can be prevented or detected early with proper measures.
Routine screenings – Colonoscopy detects polyps before they become cancerous.
Healthy diet – Eat fiber-rich foods like vegetables, fruits, and whole grains.
Limit processed and red meat – Reduces cancer risk.
Exercise regularly – Staying active lowers the chances of colorectal cancer.
Avoid smoking and alcohol – Reduces inflammation and genetic damage.
Maintain a healthy weight – Obesity is a known risk factor.
Coping with colorectal cancer involves physical, emotional, and lifestyle adjustments.
Follow-up care – Regular check-ups to monitor for recurrence.
Nutritional support – A balanced diet supports immune function and recovery.
Physical activity – Light exercise boosts energy and overall well-being.
Support groups and counseling – Helps in managing emotional stress.
Managing treatment side effects – Proper care can reduce discomfort from chemotherapy or radiation.