📌 Definition
Colorectal cancer is a malignant neoplasm arising from the epithelial lining of the colon and/or rectum, commonly originating from adenomatous polyps and developing into adenocarcinoma.
🧠 Anatomy & Physiology: Colon & Rectum
- Colon: Absorbs water/electrolytes, forms feces
- Sections: Ascending, Transverse, Descending, Sigmoid
- Rectum: Stores feces prior to defecation
- Lining: Simple columnar epithelium (malignancy site)
- Lymphatics: Spread via blood/lymph to liver, lungs
⚠️ Etiology: Causes & Risk Factors
Non-modifiable:
- Age > 50
- Family history of CRC or polyps
- Genetic syndromes (FAP, Lynch)
Modifiable:
- Low-fiber, high-fat diet
- Obesity, inactivity
- Smoking, alcohol use
- Inflammatory bowel disease (IBD)
🩺 Symptomatology
Right-sided colon cancer: Occult bleeding, anemia, vague pain
Left-sided colon cancer: Bowel habit change, ribbon-like stool, visible bleeding
Rectal cancer: Tenesmus, bright red bleeding, painful defecation
Systemic: Weight loss, weakness, anorexia
🔁 Pathophysiology (Simplified)
- Mutation in epithelial cells → polyp forms
- Polyp → dysplasia → carcinoma in situ
- Invasion of colon wall
- Metastasis via blood/lymph → liver, lungs, bones
🧪 Medical Management
🔬 Labs & Diagnostics
- Colonoscopy with biopsy – gold standard
- CEA – tumor marker
- CT scan – staging, metastasis
💊 Medications
- 5-FU – chemotherapy standard
- Oxaliplatin, Irinotecan – advanced disease
- Targeted: Bevacizumab, Cetuximab
🛠️ Treatments
- Surgery: Hemicolectomy, APR
- Colostomy (temporary/permanent)
- Radiation (especially for rectal CA)
- Chemo (adjuvant/neoadjuvant)
🧑⚕️ Nursing Management: 5 Key Interventions
- Monitor bowel patterns & rectal bleeding
- Assist & educate in colostomy care
- Manage chemotherapy/radiation side effects
- Ensure adequate nutrition & hydration
- Support body image & emotional well-being
🩹 Priority Nursing Diagnoses
- Imbalanced nutrition: Less than body requirements
- Risk for ineffective GI perfusion
- Disturbed body image
- Acute pain
- Anxiety
📉 Prognosis
- Stage I: ~90% 5-year survival
- Stage II–III: 70–85%
- Stage IV: <15%
Reminder: Early screening (e.g., colonoscopy) dramatically improves outcomes.
