Unfortunately, a number of patients treated for head and neck malignancies will develop:
- Local recurrence of their original disease
- New second primary of the head and neck
- Distant metastases
Distant metastases are treated with systemic therapy with some effect (usually a cisplatin based therapy if within tolerance). Local recurrences of head and neck cancer may be symptomatic and significantly reduce quality of life. Second malignancies can lead to similar complications.
The options for treatment of local recurrence are:
- Surgical resection (if possible)
- Systemic therapy
If the disease is operable, surgery should be considered. Patients may refuse surgery that is too disfiguring or defunctioning (eg. glossectomy, laryngectomy). Surgery is curative in about 1/3rd of patients with 'resectable' disease but positive margins are not uncommon and local recurrence may occur regardless of margin status.
Systemic therapy (usually cisplatin based) may lead to responses in 1/3rd of head and neck tumours; these responses are usually short-lived.
Due to the poor outcomes with surgery and systemic therapy, radiotherapy may be considered even when there has been previous high dose radiotherapy to the neck. Typically, radiation can be considered when:
- There has been a suitable time difference between the original treatment and recurrence (preferably 2 years or more)
- The patient has not developed grade 3 or 4 late toxicities from the original course of treatment (these patients are usually excluded from reirradiation trials)
- Radiotherapy will not exceed dose contraints of the spinal cord (often necessitating IMRT)
The prescribed dose should be at least 60 Gy to ensure the potential for local control. Treatment of macroscopic tumour (or the tumour bed) is always recommended; treatment of regional nodes is more controversial.
Evidence for Re-Irradiation
There is a single randomised controlled trial comparing salvage surgery alone versus salvage surgery with chemoradiotherapy. Patients were enrolled after achieving macroscopic clearance of tumour recurrence with surgery and were prescribed 60 Gy.
There are two non-randomised RTOG trials that explored concurrent chemoradiotherapy. With concurrent paclitaxel and cisplatin with radiotherapy, two year survival rates of 26% were seen. There is bound to be selection bias in these trials but long term cures are possible.