Treatment Options for Colorectal Cancer

This detailed guide provides an in-depth look at the comprehensive treatment strategies for colorectal cancer, including surgery, chemotherapy, radiation therapy, targeted therapy, immunotherapy, clinical trials, and supportive care. By understanding the available options, patients and caregivers can make informed decisions tailored to their needs and goals.

1. Surgery

Surgery is often the first line of treatment for localized colorectal cancer and plays a critical role in managing advanced cases.

A. Polypectomy and Local Excision

• When Used:
  • For early-stage cancers (Stage 0 or I) confined to polyps or the innermost layer of the colon or rectum.
• Procedure:
  • Polypectomy: Removal of cancerous polyps during a colonoscopy using a snare or forceps.
  • Local Excision: Removes a small section of the colon or rectum wall containing the tumor.
• Recovery:
  • Outpatient procedure with minimal recovery time.

B. Colectomy (Colon Resection)

• When Used:
  • For Stage II or III cancers and larger tumors.
• Procedure:
  • Removes the cancerous section of the colon or rectum along with nearby lymph nodes.
  • Reconnects the healthy portions of the colon (anastomosis).
• Types:
  • Right Hemicolectomy: Removes the right side of the colon.
  • Left Hemicolectomy: Removes the left side of the colon.
  • Sigmoid Colectomy: Removes the sigmoid colon.
  • Total Colectomy: Removes the entire colon, often used for hereditary conditions.
• Recovery:
  • Hospital stay of 3–7 days, full recovery in 4–6 weeks.

C. Rectal Cancer Surgery

• When Used:
  1. For cancers in the rectum.
• Types:
  1. Low Anterior Resection (LAR):
     • Removes tumors in the upper two-thirds of the rectum.
     • Preserves the anal sphincter for normal bowel function.
  2. Abdominoperineal Resection (APR):
     • Removes the entire rectum and anus.
     • Requires a permanent colostomy.
  3. Transanal Excision:
     • Removes small tumors through the anus without external incisions.

D. Colostomy or Ileostomy

• When Used:
  • If reconnecting the colon is not possible immediately (temporary) or at all (permanent).
• Procedure:
  • A stoma is created to divert waste into a colostomy or ileostomy bag.
• Recovery and Lifestyle:
  • Patients are trained in stoma care by specialized nurses.

E. Metastasectomy

• When Used:
  • For Stage IV cancers with metastasis to organs like the liver or lungs.
• Procedure:
  • Surgical removal of metastatic tumors to reduce tumor burden and improve survival.
• Common Sites for Metastasectomy:
  • Liver: Partial hepatectomy.
  • Lungs: Wedge resection or lobectomy.

2. Chemotherapy

Chemotherapy is used to treat colorectal cancer by killing rapidly dividing cells. It can be administered orally, intravenously, or through regional delivery.

A. When Chemotherapy is Used

• Neoadjuvant Chemotherapy:
  • Administered before surgery to shrink tumors and improve resectability.
• Adjuvant Chemotherapy:
  • Administered after surgery to destroy remaining cancer cells and reduce recurrence risk.
• Palliative Chemotherapy:
  • Used for advanced or metastatic cancer to control tumor growth and alleviate symptoms.

B. Common Chemotherapy Regimens

• FOLFOX:
  • Combination of 5-Fluorouracil (5-FU), leucovorin, and oxaliplatin.
  • Standard for Stage III and some Stage II cancers.
• CAPOX:
  • Combination of capecitabine (oral) and oxaliplatin.
  • An alternative to FOLFOX.
• FOLFIRI:
  • Combination of 5-FU, leucovorin, and irinotecan.
  • Used for metastatic or recurrent colorectal cancer.
• Single-Agent Capecitabine:
  • Oral chemotherapy for patients unable to tolerate combination regimens.

C. Side Effects of Chemotherapy

• Acute: Nausea, vomiting, diarrhea, fatigue, hair thinning, mouth sores.
• Cumulative: Neuropathy (oxaliplatin), bone marrow suppression (low blood counts).
• Management:
  • Anti-nausea medications (ondansetron, metoclopramide).
  • Hydration and electrolyte replenishment.
  • Ice gloves and socks during infusion to prevent neuropathy.

3. Radiation Therapy

Radiation therapy uses high-energy beams to target and destroy cancer cells. It is more commonly used for rectal cancer than colon cancer.

A. Types of Radiation Therapy

• External Beam Radiation Therapy (EBRT):
  • Delivered externally over several sessions.
  • Often combined with chemotherapy for rectal cancer.
• Internal Radiation Therapy (Brachytherapy):
  • Places radioactive material directly near the tumor.

B. When Radiation is Used

• Neoadjuvant: To shrink tumors before surgery.
• Adjuvant: To kill residual cancer cells post-surgery.
• Palliative: To relieve symptoms like pain or bleeding in advanced cases.

C. Side Effects of Radiation Therapy

• Skin irritation, rectal discomfort, bowel changes, fatigue.
• Management:
  • Use gentle skincare products and maintain hydration.
  • Anti-diarrheal medications (loperamide) for bowel changes.

4. Targeted Therapy

Targeted therapies focus on specific molecules involved in cancer growth, sparing normal cells.

A. Anti-VEGF Therapy

• Drugs: Bevacizumab (Avastin), Ramucirumab (Cyramza).
• Purpose: Blocks blood vessel formation in tumors.

B. Anti-EGFR Therapy

• Drugs: Cetuximab (Erbitux), Panitumumab (Vectibix).
• Eligibility:
  • Effective only in patients with KRAS and NRAS wild-type tumors.
• Side Effects:
  • Skin rash, diarrhea, low magnesium levels.

C. BRAF-Targeted Therapy

• Drugs: Encorafenib (Braftovi), combined with cetuximab or panitumumab.
• When Used:
  • For metastatic colorectal cancers with BRAF mutations.

5. Immunotherapy

Immunotherapy boosts the body’s natural immune system to fight cancer cells.

A. Checkpoint Inhibitors

• Drugs: Pembrolizumab (Keytruda), Nivolumab (Opdivo).
• Eligibility:
  • For patients with microsatellite instability-high (MSI-High) or mismatch repair-deficient (dMMR) tumors.
• Side Effects:
  • Immune-related adverse events (e.g., colitis, rash, thyroid dysfunction).

6. Clinical Trials

Participation in clinical trials provides access to cutting-edge therapies:

• Investigational immunotherapies.
• Novel drug combinations.
• Personalized medicine approaches targeting rare mutations.

7. Palliative and Supportive Care

For advanced colorectal cancer:

• Pain Management: Opioids, nerve blocks.
• Nutritional Support: Feeding tubes or supplements for severe weight loss.
• Emotional Support: Counseling and support groups.

Conclusion

Treatment for colorectal cancer is highly individualized, integrating surgery, chemotherapy, radiation therapy, and advanced therapies based on the stage and molecular profile. Collaborating with a multidisciplinary team ensures the best approach to managing this complex disease.

Going through treatment and need help understanding how to manage side effects? See Wellnest's guide for the Managing Side Effects of Colorectal Cancer Treatment, Must-Have Items for Going Through Treatment, and Questions to Ask the Doctor.