Positron emission tomography [Part 2(ii)]
Medical Services Advisory Committee
Record ID 32002000830
The clinical effectiveness of FDG PET has been assessed previously for eleven indications, in two reviews (lung cancer, metastatic melanoma, malignant glioma, colorectal cancer, refractory epilepsy, and myocardial viability, ovarian cancer, cervical cancer, endometrial cancer, oesophageal carcinoma and gastric carcinoma. The current review assesses an additional three clinical questions. The areas covered are:
- assessment of patients with lymphoma (Hodgkin-s disease and non-Hodgkin-s lymphoma) for staging of disease prior to therapy; - assessment of patients with squamous cell carcinoma (SCC) of the head and neck for staging prior to initial definitive treatment - assessment of patients with sarcoma (soft tissue and bone) for staging and grading of disease.
Authors' results and conclusions:
Safety: It is generally accepted that PET is a noninvasive and relatively safe diagnostic procedure. Safety issues are primarily discussed in terms of the safety of the positronemitting radiopharmaceutical, rather than the safety of the procedure as a whole.
In a large study of 22 FDG PET centres in the United States no adverse reactions to positron-emitting radiopharmaceuticals were reported for 33,295 retrospective doses of positron-emitting radiopharmaceuticals from before 1994 or 47,876 prospective doses from 1994 to 1997.
The United States Pharmacopoeia drug information for FDG also indicates that there are no known adverse effects associated with the use of FDG. In addition, radiotracers are generally used in microgram quantities, and the incidence of adverse reactions to very small amounts of labelled molecules is likely to continue to be low.
Diagnostic accuracy: PET has improved diagnostic accuracy over conventional imaging in a number of indications. PET has good diagnostic accuracy for the staging and re-staging of patients with lymphoma, for the detection of extent of primary and nodal metastatic involvement in the pre-treatment staging of patients with SCC of the head and neck and for the detection of visceral metastases in patients with soft tissue sarcoma (STS). It also appears to have good diagnostic accuracy in the assessment of residual mass in patients with lymphoma, of residual or recurrent disease in head and neck cancer patients and locally recurrent disease in patients with sarcoma. PET appears to be of value in the detection of occult squamous cell primary tumours in patients diagnosed with SCC cervical node metastases, particularly where other methods have failed to identify the tumour. However, as with other imaging modalities, PET still has low sensitivity for the detection of early (ie low volume or microscopic) metastatic disease. In each of these examples, PET has demonstrated improvements in diagnostic accuracy; however, the degree of improvement is sometimes difficult to quantify because of potential issues in the way in which patients were selected for studies or the information used to direct how reference standards were performed.
MSAC concludes that there is insufficient evidence on FDG PETs clinical effectiveness or cost-effectiveness with respect to the indications reviewed to warrant unrestricted Medicare Benefits Schedule funding. However, the evidence suggests that FDG PET is safe, has good diagnostic accuracy and is potentially clinically effective and potentially cost-effective in the indications reviewed. On this basis, MSAC recommends that FDG PET be funded on an interim basis for the following clinical scenarios:
Lymphoma: - FDG PET study for staging of newly diagnosed or previously untreated Hodgkins or non-Hodgkins lymphoma; - FDG PET study for evaluation of a residual mass after treatment of Hodgkins or non-Hodgkins lymphoma; and - FDG PET study for restaging of suspected recurrent or residual Hodgkins or non-Hodgkins lymphoma.
Squamous cell carcinoma of the head and neck: - FDG PET study for the primary staging of SCC of the head and neck; - FDG PET study for the further investigation of suspected residual or recurrent SCC of the head and neck; and - FDG PET study for the evaluation of metastatic SCC involving cervical nodes from an unknown primary site.
Sarcoma: - FDG PET study to guide biopsy of suspected bone or STS, where structural imaging suggests lesion heterogeneity; - FDG PET study for staging of biopsy-proven bone or STS being considered for resection of the primary or limited metastatic disease; and - FDG PET study for the evaluation of suspected residual or recurrent sarcoma on structural imaging after definitive therapy.
English language abstract:
An English language summary is available
- Costs and Cost Analysis
- Neoplasms, Squamous Cell
- Tomography, Emission-Computed
Medical Services Advisory Committee
MSAC (MDP 107), GPO Box 9848, Canberra, ACT 2601, Australia. Tel: +61 2 6289 6811; Fax: +61 2 6289 8799.
Medical Services Advisory Committee (MSAC)