Low incidence of malignancy in patients with suspected polymyalgia rheumatica or giant cell arteritis, examined with FDG-PET/CT.

Introduction: The need to systematically examine patients suspected of polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) for malignancy is controversial. The aim of this study was to assess the frequency of malignancy in patients with suspected PMR and/or GCA who have been referred to a 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography with computed tomography (FDG-PET/CT) as part of the diagnostic investigation. Method: The records of all patients referred to FDG-PET/CT from Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup with the suspicion of PMR and/or GCA during a two-year period, were retrospectively reviewed. Data was analyzed with descriptive statistics, and a standard incidence ratio was calculated based on background cancer incidences extracted from the NORDCAN database. Results: 220 patients were included in the study. Findings suspicious of malignancy were found in 19 of the examinations, and in seven cases (3.2%), malignancy was confirmed. In three out of the seven cases the patients were diagnosed with PMR concomitantly with malignancy. The estimated standardized incidence ratio (SIR) for cancer compared to the background incidence of cancer in Denmark was 1.58 (95% CI 0.63-2.97), i.e., not statistically significant. There were no statistically significant differences in characteristics of the patients that were diagnosed with malignancy compared with those that were not. Conclusion: The frequency of malignancy in this cohort of patients with suspected PMR/GCA who underwent PET/CT was low. Our results, though based on a small cohort, do not suggest that all patients with suspected PMR/GCA should systematically be examined with FDG-PET/CT for excluding malignancy.

Comparison of temporal artery ultrasound versus biopsy in the diagnosis of giant cell arteritis.

BACKGROUND/OBJECTIVES: Giant cell arteritis (GCA) is a medical and ophthalmological emergency due to risk of stroke and sudden irreversible loss of vision. Fast and accurate diagnosis is important to prevent complications and long-term high dose glucocorticoids toxicity. Temporal artery biopsy is gold standard for diagnosing GCA. However, temporal artery ultrasound is a fast and non-invasive procedure which may provide a supplement or an alternative to biopsy. This study assesses the diagnostic performance of ultrasound and biopsy in the diagnosis of GCA. SUBJECTS/METHODS: Examination results of patients suspected of having GCA in the period from August 2018 to June 2019 were reviewed. Patients underwent clinical examination and blood tests. Within a few days of starting glucocorticoid treatment, temporal ultrasound and unilateral biopsy were performed. Experienced physicians established the final clinical diagnosis at 6-months follow-up. RESULTS: Seventy-eight patients underwent both ultrasound and biopsy. Thirty-five (45%) received the final clinical diagnosis of GCA. Compared with the final clinical diagnosis, biopsy had a sensitivity of 69% (51-83%) and a specificity of 100% (92-100%), and ultrasound a sensitivity of 63% (45-79%) and a specificity of 79% (64-94%). Area under the receiver operating characteristics curves were 0.84 and 0.71 for biopsy and ultrasound respectively (p = 0.048). False negative rate of ultrasound was 4 out of 78 (5%). CONCLUSION: Sensitivity of ultrasound is almost on par with that of biopsy although the overall diagnostic accuracy of ultrasound was slightly lower. We find that ultrasound is a reliable tool for first line diagnosis of GCA.

Multimodality Imaging in Cranial Giant Cell Arteritis: First Experience with High-Resolution T1-Weighted 3D Black Blood without Contrast Enhancement Magnetic Resonance Imaging.

In order to support or refute the clinical suspicion of cranial giant cell arteritis (GCA), a supplemental imaging modality is often required. High-resolution black blood Magnetic Resonance Imaging (BB MRI) techniques with contrast enhancement can visualize artery wall inflammation in GCA. We compared findings on BB MRI without contrast enhancement with findings on 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/low-dose computed tomography (2-[18F]FDG PET/CT) in ten patients suspected of having GCA and in five control subjects who had a 2-[18F]FDG PET/CT performed as a routine control for malignant melanoma. BB MRI was consistent with 2-[18F]FDG PET/CT in 10 out of 10 cases in the group with suspected GCA. In four out of five cases in the control group, the BB MRI was consistent with 2-[18F]FDG PET/CT. In this small population, BB MRI without contrast enhancement shows promising performance in the diagnosis of GCA, and might be an applicable imaging modality in patients.

Bilateral Vertebral Artery Vasculitis-A Rare Manifestation of Giant Cell Arteritis and a Difficult Diagnosis Made Possible by 2-[18F]FDG PET/CT.

Giant cell arteritis (GCA) is the most common form of large vessel vasculitis. GCA is a medical and ophthalmological emergency, and rapid diagnosis and treatment with high-dose corticosteroids is critical in order to reduce the risk of stroke and sudden irreversible loss of vision. GCA can be difficult to diagnose due to insidious and unspecific symptoms-especially if typical superficial extracranial arteries are not affected. In these cases, verification of clinical diagnosis using temporal artery biopsy is not possible. This example illustrates the diagnostic value of hybrid imaging with 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]FDG PET/CT), and the limitations of the temporal artery biopsy in bilateral vertebral GCA, causing transient ischemic attack in the visual cortex. In addition it indicates that inflammation in the artery wall can be visualized on 2-[18F]FDG PET/CT despite long term and ongoing high dose glucocorticoid treatment.

Primary Cardiac Intimal Sarcoma Visualized on 2-[18F]FDG PET/CT.

Primary cardiac tumors are extremely rare, with an incidence of 0.001-0.03%. Twenty-five percent of these tumors are malignant, with sarcomas accounting for approximately 95%. Cardiac intimal sarcoma is the least reported subtype of primary cardiac sarcoma. These endocardial mesenchymal tumors most often arise from great arterial vessels, and are rarely located in the heart. They often present with an aggressive clinical course and have a poor prognosis, with surgical resection with achievement of free margins being the mainstay of treatment. This emphasizes the importance of an early, correct diagnosis and timely intervention. We report a 60-year-old Caucasian male with several former cardiac surgical procedures due to congenital aortic stenosis, presenting with functional mitral stenosis/insufficiency and left ventricular outflow tract obstruction (LVOTO) due to massive masses in the left ventricle and atrium of the heart. Hybrid imaging with 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]FDG PET/CT) was performed prior to surgery to characterize the intracardiac masses and estimate tumor burden, as well as to identify a potential extracardiac primary malignancy.

Stewart-Treves Syndrome on the Lower Extremity Associated to Idiopathic Chronic Lymphedema Visualized on FDG PET/CT.

Angiosarcomas are highly malignant and rare tumors of vascular or lymphatic endothelial cell origin with a poor prognosis. Lymphangiosarcoma associated with chronic lymphedema is known as Stewart-Treves syndrome. Stewart-Treves syndrome is primarily described in patients with lymphedema of an upper extremity occurring after breast cancer surgery including radical axillary lymph node dissection and subsequent radiotherapy. It is rarely described in the presence of idiopathic chronic lymphedema of the lower extremities. We present a case of lymphangiosarcoma visualized on F-FDG PET/CT, where Stewart-Treves syndrome is secondary to probably a combination of idiopathic chronic lymphedema of the lower extremities and systemic immunosuppressive treatment.

Hepatobiliary scintigraphy for early diagnosis of biliary atresia.

INTRODUCTION: The aim of this study was to evaluate the validity of (99m)Technetium-trimethylbromo-iminodiacetic acid hepatobiliary scintigraphy (HS) for the diagnosis of biliary atresia (BA). METHODS: From January 2005 to December 2009, a total of 47 infants with conjugated hyperbilirubinaemia (> 20 micromol/l total bilirubin of which 20% is conjugated) underwent HS. BA was suspected if no tracer was visualised in the gut 24 hours post-injection. The results of the HSs were compared with the gold standard, laparotomy with antegrade cholangiography findings. RESULTS: Considering the final diagnosis based on the gold standard, the sensitivity, specificity, positive predictive value and negative predictive value (NPV) of the HS in the diagnosis of BA was 100%, 63.6%, 53.8%, and 100%, respectively. The accuracy was 74.5%. BA patients with non-draining HS had significantly higher levels of gamma-glutamyl transpeptidase (GGTP) than non-BA patients with non-draining HS (p = 0.019) or draining HS (p = 0.0001). CONCLUSIONS: HS plays an important role in the diagnostic strategy of infantile jaundice due to conjugated hyperbilirubinaemia. It is a non-invasive method that only seldomly calls for sedation. A high sensitivity and NPV prevent un-necessary surgery. Because of the low specificity of HS in diagnosing BA, it should be part of a multimodality imaging strategy when the result supports a clinical suspicion of BA. In cases with non-draining HS and normal GGTP blood levels, supplemental imaging modalities are especially needed. FUNDING: none. TRIAL REGISTRATION: not relevant.