What is Chemoradiation?
Chemoradiation (CRT) refers to the concurrent use of chemotherapy and radiation therapy to treat cancer.
- Purpose:
- Also called: concurrent chemoradiotherapy (CCRT)
Mechanism
- Chemotherapy can increase tumor cell sensitivity to radiation by:
- Radiation directly damages DNA → double-strand breaks → apoptosis
Common Chemoradiation Regimens by Cancer Type
| Cancer Type | Chemotherapy Used | Radiation Details | Notes / Pearls |
|---|---|---|---|
| Rectal cancer | 5-FU (continuous infusion) or Capecitabine (oral) | 45–50.4 Gy in 25–28 fractions | Neoadjuvant CRT standard for locally advanced rectal cancer; reduces local recurrence |
| Anal cancer | 5-FU + Mitomycin C | 45–59 Gy | Standard definitive CRT (Nigro protocol); avoids surgery |
| Head & Neck (HNSCC) | Cisplatin IV (high-dose q3w or weekly low-dose) | 66–70 Gy | Organ preservation (larynx, oropharynx); concurrent therapy improves OS |
| Esophageal cancer | Carboplatin + Paclitaxel | 41.4–50.4 Gy | CROSS trial standard; neoadjuvant therapy before surgery |
| Cervical cancer | Cisplatin weekly | 45–50 Gy + brachytherapy boost | Definitive CRT for locally advanced disease |
| NSCLC (Stage III) | Cisplatin + Etoposide or Carboplatin + Paclitaxel | 60–66 Gy | Definitive CRT; concurrent preferred over sequential for survival |
Key Pharmacist Considerations
- Drug selection:
- Often uses radiosensitizing chemo: 5-FU, capecitabine, cisplatin, paclitaxel.
- Toxicity management:
- Overlapping toxicities with radiation: mucositis, esophagitis, dermatitis, diarrhea, cytopenias.
- Supportive care (hydration, antiemetics, growth factors if needed).
- Scheduling:
- Monitoring:
- CBC, renal/hepatic function, hydration status, electrolyte balance
- Assess skin, mucosa, GI for radiation–chemo overlap toxicity
- Patient counseling:
- Fatigue, skin care, oral care, diarrhea management
- Importance of adherence, especially with oral radiosensitizers like capecitabine
Summary:
Chemoradiation = concurrent chemotherapy + radiation to enhance tumor control.
- Common in rectal, anal, head & neck, cervical, esophageal cancers.
- Choice of chemo depends on tumor type and radiosensitizing effect.
- Requires careful toxicity monitoring and supportive care.