Clinical trial NCT03409913: Diagnostic Accuracy of FDG PET/CT of Cranial Arteries in GCA
Official title: Conventional FDG PET/CT Accurately Diagnoses Temporal Arteritis in Glucocorticoid-naïve GCA Patients: a Case-control Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Giant Cell Arteritis
Keywords: positron emissions tomography
diagnostic accuracy
case-control
Lead sponsor: University of Aarhus
Sponsor class: OTHER
First posted: 2018-01-24
Enrollment: 106
Sex: ALL
Minimum age (years): 50
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: RETROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: All patients are sampled from tertiary hospital. Cases are identified in an established cohort of patients suspected og GCA in whom clinical assessment, including imaging procedures were performed before treatment.

Controls are sampled among malignant melanoma patients who had a clinically indicated follow-up FDG PET/CT to evaluate disease freedom/progression.

Brief summary: A case-control study to evaluate the diagnostic accuracy of FDG uptake in cranial arteries by FDG PET/CT in the diagnosis of giant cell arteritis.

Detailed description: Although older studies argue that FDG PET/CT cannot demonstrate inflammation in cranial arteries, e.g. temporal and maxillary arteries, the resolution of modern PET systems may have improved, making a case for FDG PET/CT. FDG PET/CT is increasingly used in giant cell arteritis (GCA) diagnosis due to its excellent diagnostic accuracy considering large-vessel involvement. In case of uncommon distribution of vessel involvement or marginally increased large-vessel FDG uptake, FDG PET/CT-specificity may be compromised. Hence, recognising FDG uptake in cranial arteries potentially adds to FDG PET/CTs diagnostic accuracy.

Objectives To evaluate the diagnostic accuracy of conventional FDG PET/CT of the cranial arteries in the diagnosis of GCA.

Methods In a cohort of consecutively included glucocorticoid-naïve patients suspected of new-onset GCA, patients with a clinical GCA diagnosis will be identified. Conventional FDG PET/CT and vascular ultrasound(US) was performed before treatment. Patients were referred for a temporal artery biopsy (TAB).

Controls are age-(+/- 3 years) and sex-matched malignant melanoma (MM) patients who had a follow-up metastatic-disease-free FDG PET/CT ≥6 months after MM resection.

Images will be assessed by 5 nuclear medicine physicians blinded to clinical symptoms and findings. Temporal (TA), maxillary (MA) and vertebral (VA) arteries will be visually assessed. Arterial FDG uptake more than FDG uptake in surrounding tissue is considered positive. Sensitivity, specificity and interreader agreement will be evaluated.

Eligibility criteria: Inclusion Criteria:

Cases:

* 1) age ≥50 years, 2) CRP\>15mg/l or ESR\>40mm/h, 3) either a) cranial symptoms, b) new-onset extremity claudication or c) weight loss \>5 kilograms or fever\>38oC for \>3 weeks and a clinical diagnosis of giant cell arteritis judged by expert rheumatologist.

Controls:

* age-(+/-3 years) and sex-matched malignant melanoma (MM) patients
* follow-up metastatic-disease-free FDG PET/CT ≥6 months after MM resection

Exclusion Criteria:

* Previous diagnosis of polymyalgia or giant cell arteritis
* immunosuppresive treatment within last month

Primary outcomes:
measure: PET positivity
timeFrame: Time of diagnosis/pre-treatment (cases)
Secondary outcomes:
measure: Full-fillment of ACR criteria
timeFrame: Time of diagnosis
measure: Temporal artery biopsy
timeFrame: Time of diagnosis
measure: Temporal artery ultrasound
timeFrame: Time of diagnosis
Other outcomes:
Locations:
city: Aarhus
country: Denmark
facility: Department of Rheumatology
Study officials:
affiliation: Department of Nuclear Medicine and PET centre, Aarhus University Hospital
name: Lars Christian Gormsen, MD, PhD
role: STUDY_CHAIR
References: