The prognostic value of baseline (18)F-FDG PET/CT in steroid-naïve large-vessel vasculitis: introduction of volume-based parameters.

PURPOSE: The aim of this study was to analyse if the result of a baseline (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT scan, in large-vessel vasculitis (LVV) patients, is able to predict the course of the disease, not only in terms of presence/absence of final complications but also in terms of favourable/complicated progress (response to steroid therapy, time to steroid suspension, relapses, etc.). METHODS: A total of 46 consecutive patients, who underwent (18)F-FDG PET/CT between May 2010 and March 2013 for fever of unknown origin (FUO) or suspected vasculitis (before starting corticosteroid therapy), were enrolled. The diagnosis of LVV was confirmed in 17 patients. Considering follow-up results, positive LVV patients were divided into two groups, one characterized by favourable (nine) and the other by complicated progress (eight), on the basis of presence/absence of vascular complications, presence/absence of at least another positive PET/CT during follow-up and impossibility to comply with the tapering schedule of the steroid due to biochemical/symptomatic relapse. Vessel uptake in subjects of the two groups was compared in terms of intensity and extension. To evaluate the extent of active disease, we introduced two volume-based parameters: "volume of increased uptake" (VIU) and "total lesion glycolysis" (TLG). The threshold used to calculate VIU on vessel walls was obtained by the "vessel to liver" ratio by means of receiver-operating characteristic analysis and was set at 0.92 × liver maximum standardized uptake value in each patient. RESULTS: Measures of tracer uptake intensity were significantly higher in patients with complicated progress compared to those with a favourable one (p < 0.05). Measures of disease extension were even more significant and TLG emerged as the best parameter to separate the two groups of patients (p = 0.01). CONCLUSION: This pilot study shows that, in LVV patients, the combined evaluation of the intensity and the extension of FDG vessel uptake at diagnosis can predict the clinical course of the disease, separating patients with favourable or complicated progress.

Role of adrenal gland scintigraphy in patients with subclinical hypercortisolism and incidentally discovered adrenal mass.

BACKGROUND: The role of adrenal scintigraphy (AS) in the diagnosis of subclinical hypercortisolism (SH) in adrenal incidentaloma (AI) is debated. AIM: To evaluate the possible role of AS in identifying SH in AI patients. SUBJECTS AND METHODS: In the retrospective phase (2000-2004), 102 AI patients [71 females (F)/31 males (M)] referred to our center were reevaluated for SH. In the prospective phase (2005-2006), 42 patients (32F/10M) with suspected SH were evaluated performing AS and biochemical assessment of cortisol secretion. We report data of the prospective phase of the study. In these patients AS was performed at baseline; the difference between the uptake of the affected and the controlateral gland [mean Delta uptake (MDeltau)] was calculated. Cortisol secretion was evaluated in 3 different occasions. Patients were considered affected with SH if they presented at least twice 2 of the following criteria: urinary free cortisol >193 nmol/l, cortisol after 1 mg dexamethasone suppression test >83 nmol/l, ACTH levels <2.2 pmol/l. RESULTS: MDeltau was higher in patients with SH (no.=27, 5/22 M/F) than in patients without SH (83.7+/-12.5 vs 54.7+/-24.1%, p<0.001), and directly correlated with UFC (beta=0.387, p=0.015) and was predictive of SH (odds ratio 1.12, 95% confidence interval 1.03-1.22, p=0.009) regardless of age, body mass index, and diameter of the mass. A 75% MDeltau cut-off has 86.7% specificity and 81.5% sensitivity in diagnosing SH. CONCLUSIONS: AS is not recommended as screening test in AI patients, but it can be useful to exclude the presence of a subtle cortisol excess in patients with unclear biochemical diagnosis of SH.

Staging and therapy monitoring of multiple myeloma by 99mTc-sestamibi scintigraphy: a five year single center experience.

The aim of the present study was the evaluation of the diagnostic value of 99mTc-sestamibi (MIBI) in the detection of bone marrow involvement in patients suffering from multiple myeloma (MM) and its possible role in the follow-up. Between 1998 and 2003, 68 patients with MM and 42 pts with monoclonal gammopathy of undetermined significance (MGUS) were consecutively enrolled in this study. 51/68 MM patients had active disease (AD), 11/62 were in complete remission (CR) and 6/68 in partial remission (PR) after chemotherapy. 18 patients with MM repeated a 99mTc-MIBI scintigraphic study at least 2 months after high-dose chemotherapy. All the scans were scored semi quantitatively according to extension and intensity of tracer uptake. All MGUS pts had a negative 99mTc-MIBI. As far as the MM pts are concerned, 54/68 (49%) pts (48 with AD, 5 with PR and 1 with CR) had a positive 99mTc-MIBI scan, while the 99mTc-MIBI scan was negative in 14/68 pts (10 with CR, 1 with PR and 3 with AD). The overall sensitivity of the 99mTc-MIBI scintigraphy was 92%; specificity was 96%. In the follow up of the pts treated with chemotherapy 99mTc-MIBI closely paralleled the activity of myeloma bone disease. In conclusion, these results indicate that 99mTc-MIBI scintigraphy closely reflects myeloma disease activity in the bone marrow, and that a negative 99mTc-MIBI scan in patients with suspected MM clearly, though not absolutely, indicates absence of disease or clinical remission. The results of this study suggest a clear diagnostic value of 99mTc-MIBI scintigraphy in patients with MM and its potential role during the follow-up for the monitoring of MM bone disease.

Retrospective analysis of the association of nodular goiter with primary and secondary hyperparathyroidism.

BACKGROUND: The association of hyperparathyroidism (HPT) with thyroid disease has long been known, but the mechanisms underlying such an association have not yet been clarified. OBJECTIVE: To elucidate the main factors determining this combination of endocrine diseases, in a retrospective multicenter study. METHODS: We retrospectively reviewed all patients referred for parathyroid scintigraphy in the period 1990-1999. A total of 487 patients in the age range 17-65 years were selected for the analysis (339 women and 148 men); group A included 241 patients with primary and group B 246 patients with secondary HPT. RESULTS: A total of 124/241 patients in group A (51.5%), but only 92/246 patients in group B (38.2%) had thyroid disorders (notably nodular goiter) associated with HPT (P=0.0035). Thyroid disorders were evenly distributed throughout the entire 17-65 years age range in group A, but 17-40-year-old patients in group B had significantly fewer thyroid disorders than the older patients of the same group (15.5% compared with 43.3%, P<0.002), as expected in a general population. In patients with primary HPT there was no difference in the prevalence of thyroid disease between women and men, whereas the ratio of women to men in secondary HPT patients with thyroid disease was about 3:1. CONCLUSIONS: These results demonstrate an increased prevalence of nodular goiter in patients with primary rather than secondary HPT, and are consistent with a possible role of increased endogenous calcium concentrations (a hallmark of primary, but not of secondary, HPT) as a goitrogenic factor in patients with HPT.

Technetium-99m-sestamibi scintigraphy in multiple myeloma and related gammopathies: a useful tool for the identification and follow-up of myeloma bone disease.

BACKGROUND AND OBJECTIVES: Technetium-99m 2-methoxy-isobutyl-isonitrile ((99m)Tc-sestamibi) has recently been proposed as a potential tracer in patients with multiple myeloma (MM), as its increased uptake in the bone marrow has been reported as indicator of myeloma activity. We evaluated the role of (99m)Tc-sestamibi scintigraphy in the detection of myeloma bone disease in MM and related gammopathies, and also assessed its relationship with clinical status and stage of the disease, focusing in particular on the early follow-up of a small series of MM patients treated with high-dose therapy. DESIGN AND METHODS: Forty-six consecutive patients affected by MM or monoclonal gammopathy of undefined significance (MGUS) were studied by whole body scans obtained 20 minutes after administration of 740 MBq of (99m)Tc-sestamibi. A semiquantitative uptake score was used and scintigraphic findings were correlated with clinical and laboratory data. RESULTS: All the MGUS patients showed a negative (99m)Tc-sestamibi scan. Among the 32 MM patients (25 with active disease and 7 in clinical remission) 24 showed a positive scan, while 8 presented only a physiologic uptake of the tracer. The uptake score correlated significantly with all the most relevant clinical variables. In the follow-up of 8 MM patients treated with high-dose chemotherapy (99m)Tc-sestamibi closely paralleled the activity of myeloma bone disease. Comparison with X-ray skeletal survey showed discordant results in 14 out of the overall 56 scans obtained (27%), with 10 cases of negative (99m)Tc-sestamibi scans but lytic bone lesions revealed by X-ray (7 of them were in clinical remission), and 4 negative X-ray surveys in patients with positive (99m)Tc-sestamibi scans. Overall sensitivity and specificity of (99m)Tc-sestamibi scintigraphy in detecting myeloma bone disease were 90% and 88%, respectively. INTERPRETATION AND CONCLUSIONS: This study provides additional evidence indicating that (99m)Tc-sestamibi scintigraphy closely reflects myeloma disease activity in bone marrow, with very high sensitivity and specificity. (99m)Tc-sestamibi scintigraphy is therefore suggested as a reliable new tool for the staging and follow-up of myeloma bone disease.