Interstitial photodynamic therapy for malignant parotid tumours (interventional procedures consultation)

NATIONAL INSTITUTE FOR HEALTH AND CLINICAL EXCELLENCE

Interventional Procedure Consultation Document

Interstitial photodynamic therapy for malignant parotid tumours

The parotid glands are located in front of the ears and help to produce saliva. Rarely, they may be affected by malignant tumours. In photodynamic therapy (usually abbreviated to PDT), a drug called a 'photosensitising agent' is injected into a vein. A few days later, special needles and fibres are inserted into the tumour and a special light is shone through them. The light causes the photosensitising agent to destroy the tumour cells.


The National Institute for Health and Clinical Excellence is examining interstitial photodynamic therapy for malignant parotid tumours and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about interstitial photodynamic therapy for malignant parotid tumours.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

  • comments on the preliminary recommendations
  • the identification of factual inaccuracies
  • additional relevant evidence.

Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that the Institute will follow after the consultation period ends is as follows.

  • The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
  • The Advisory Committee will then prepare draft guidance which will be the basis for the Institute's guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.

For further details, see the Interventional Procedures Programme manual, which is available from the Institute's website (www.nice.org.uk/ipprogrammemanual).

NICE is committed to promoting through its guidance race and disability equality and equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our guidance on interventional procedures. In particular, we aim to encourage people and organisations from groups in the population who might not normally comment on our guidance to do so. We also ask consultees to highlight any ways in which draft guidance fails to promote equality or tackle discrimination and how it might be improved.

Closing date for comments: 30 January 2008
Target date for publication of guidance: April 2008


Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.


1 Provisional recommendations
1.1 Current evidence on the safety and efficacy of interstitial photodynamic therapy (PDT) for malignant parotid tumours is inadequate in quantity. Therefore this procedure should only be used with special arrangements for clinical governance, consent and audit or research.
1.2

Clinicians wishing to undertake interstitial PDT for malignant parotid tumours should take the following actions.

  • Inform the clinical governance leads in their Trusts.
  • Ensure that patients understand the uncertainty about the procedure's safety and efficacy, and provide them with clear written information. In addition, the use of the Institute?s information for patients ('Understanding NICE guidance') is recommended (available from www.nice.org.uk/IPGXXXpublicinfo). [[details to be completed at publication]]
  • Audit and review clinical outcomes of all patients having interstitial PDT for parotid malignancies (see section 3.1).
1.3 Further publication of safety and efficacy outcomes will be useful. The Institute may review the procedure upon publication of further evidence.
   
2 The procedure
2.1 Indications and current treatments
2.1.1 The parotid glands are salivary glands located in front of the ears. Rarely, primary malignant tumours can develop in the parotids (benign tumours are more common). The tumours typically first present with painless, localised swelling on one side of the face.
2.1.2 Conventional treatment for malignant parotid tumours involves surgical excision. Superficial parotidectomy with careful dissection and preservation of the facial nerve is the most common surgical treatment. Superficial parotidectomy can also be used to establish a definitive diagnosis of the tumour. If malignancy is diagnosed, more extensive surgery may be required. Radiotherapy and chemotherapy may also be used in the treatment of malignant parotid tumours.    
2.1.3 PDT may be used for patients whose parotid tumours are refractory to other forms of treatment or for those with recurrent parotid tumours.    
2.2 Outline of the procedure
2.2.1 PDT involves initial administration of a photosensitising agent by intravenous injection. A few days later, the procedure is performed under local or general anaesthetic. A number of needles are inserted into the parotid tumour, either percutaneously or transorally, with the use of ultrasound, computed tomography or magnetic resonance imaging guidance. The required number and length of the needles depend on the size and position of the tumour. A beam splitter is used to split a primary laser beam of appropriate wavelength into a small number of optic fibres, which are passed through the needles to deliver laser light into the tumour. Light dosimetry calculations are made dependent upon the dose of light required and the output of the laser. After the deepest portion of the tumour has been treated, the needles and laser fibres are pulled back in 1-cm decrements, each withdrawal being followed by further illumination. The illumination of the photosensitive agent results in the formation of high-energy, cytotoxic oxygen molecules.
2.2.2 After administration of the photosensitising agent, patients need to follow a regimen of controlled re-exposure to ambient light over a period of 2 to 3 weeks.    
Sections 2.3 and 2.4 describe efficacy and safety outcomes which were available in the published literature and which the Committee considered as part of the evidence about this procedure. For more details, refer to the sources of evidence (see appendix).    
2.3 Efficacy
2.3.1 One report described two patients with parotid tumours treated with PDT. One of these patients, a 42-year-old woman with a stage T4 adenoid cystic carcinoma of the parotid gland, had a complete response to PDT at 4 weeks and was alive and well with no evidence of recurrence at 15-month follow-up. The other patient was described as responding to treatment but no additional information was provided. A second report described a single patient with parotid tumour, who was still alive 3 years after treatment.
2.3.2 The Specialist Advisers considered the main efficacy outcome to be local tumour control.
2.4 Safety
2.4.1 No complications attributable to PDT were described for the two patients in the report (see 2.3.1).
2.4.2 The Specialist Advisers considered theoretical adverse events to include photosensitisation that may result in burns to non-treated areas, allergic reactions to the photosensitising agent, nerve and blood vessel damage, bleeding and delayed healing.
3 Further information
3.1 This guidance requires that clinicians undertaking the procedure make special arrangements for audit. The Institute has identified relevant audit criteria and is developing an audit tool (which is for use at local discretion), which will be available when the guidance is published.
3.2 The Institute has produced interventional procedures guidance on palliative photodynamic therapy for both early-stage and advanced oesophageal cancer (www.nice.org.uk/IPG200, www.nice.org.uk/IPG206), photodynamic therapy for high-grade dysplasia in Barrett?s oesophagus (www.nice.org.uk/IPG082), photodynamic therapy for localised inoperable endobronchial cancer (www.nice.org.uk/IPG137), photodynamic therapy for advanced bronchial carcinoma (www.nice.org.uk/IPG087), photodynamic therapy for bile duct cancer (www.nice.org.uk/IPG134), and photodynamic therapy for non-melanoma skin tumours (www.nice.org.uk/IPG155).
   

Bruce Campbell
Chairman, Interventional Procedures Advisory Committee
January 2008

Appendix: Sources of evidence
 

The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.

  • 'Interventional procedure overview of interstitial photodynamic therapy for malignant parotid tumours', October 2007

Available from: http://www.nice.org.uk/guidance/index.jsp?action=download&o=38780.

This page was last updated: 30 March 2010