Radiotherapy

Radiotherapy can be used in several situations for oesophageal cancer:

  • Definitive radiotherapy (rarely used except in patients unable to receive 5-FU/cisplatin)
  • Definitive chemoradiotherapy (in patients with unresectable disease or instead of surgery)
  • Neoadjuvant chemoradiotherapy (in patients with resectable disease T2+ or N1)
  • Palliative radiotherapy (in patients with metastatic disease)
  • Brachytherapy (for palliation of dysphagia in select patients)

Definitive Chemoradiotherapy (Thoracic oesophagus)

Pre-Simulation

  • Informed consent
  • Other Specialists: Medical oncologist
  • Allied Health: Dietician

Simulation

  • Position: Supine
  • Immobiisation: Arms elevated on wingboard, kneefix
  • Bolus: Not required
  • CT: Base of skull to anterior superior iliac spine
  • Contrast: Use if possible
  • Organ motion: Consider 4D CT to evaluate movement of tumour

Planning

  • Fusion: Fuse with PET-CT
  • Volumes:
    • GTV = volume visible on CT, correlated with endoscopy and PET findings
    • CTV = 3 cm craniocaudal expansion (skip lesions) and 1 cm axial expansion respecting tissue planes
    • PTV = 1 cm craniocaudal and 0.5 cm axial expansion
  • Dose: 50.4 Gy in 28 fractions
  • Beam Arrangement:
    • Anterior and 2 posterior obliques
    • Anterior, posterior and two lateral obliques
    • 2 phase technique - APPA until 40 Gy, then off-cord technique (spares lung tissue)
  • OAR: Spinal cord < 40 Gy, Lung (mean < 20 Gy, V20 < 30%, V30 < 20%), Heart V30 < 50%

Outcomes

  • Cure: 20% 5 year survival
  • Early: Dysphagia, fatigue, nausea/vomiting (if lower oesophagus treated)
  • Late: Cosmetic skin changes, oesophageal stricture (5-10%), tracheo-oesophageal fistula (5%), radiation pneumonitis (< 10%), ischaemic heart disease, myelopathy (< 0.2%), second cancers (< 1%).

Neoadjuvant Chemoradiotherapy

As above, but with cure of 30%.


Palliative Radiotherapy

Pre-Simulation

  • Informed Consent
  • Other specialists: Palliative care physician
  • Allied health: Dietician, palliative care nurses

Simulation

  • Position: Supine
  • Immobilisation: Arms by side, headrest, kneefix
  • CT: Base of skull to ASIS
  • Contrast: Not necessary
  • 4D: Not necessary

Planning

  • Fusion: Not necessary
  • Volumes:
    • GTV: Visible tumour (correlate with endoscopic/PET findings)
    • PTV: GTV + 3 cm (craniocaudal) or 2 cm (axial)
  • Dose: 30 Gy in 10 fractions
  • Beam Arrangement: APPA
  • OAR: Unlikely to exceed tolerance of spinal cord, lung with 30 Gy in 10 fractions and APPA technique

Outcomes

  • Palliation of dysphagia: 75% at 3 months, 50% until death
  • Early effects: Dysphagia, fatigue
  • Late effects: Radiation pneumonitis < 1%, myelopathy < 0.1%

Brachytherapy

Suitable for short stenosing tumours; stenting is easier to obtain and works immediately. There are no head to head trials.
Brachytherapy can be used in conjunction with chemoradiotherapy as a boost; it may be associated with additional complications.

Procedure

HDR catheter is inserted into a 16 G nasogastric tube and taped to distal end.
Nasogastric tube inserted. Verification with X-ray or CT essential (I would prefer CT planning).
Dose prescribed to 1 cm depth. Dose should cover tumour volume with 2 cm expansion craniocaudally.
15 Gy prescribed to 1 cm.

Outcomes

Good palliation of dysphagia. Early effects of dysphagia. Late effects of oesophageal stricture, tracheo-oesophageal fistula.


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