Increased splenic fluorodeoxyglucose uptake in a patient with granulomatous angitis

Splenic FDG uptake predicts poor prognosis in patients with unresectable cholangiocarcinoma

Aim: Diffuse splenic 18F-Fluorodeoxyglucose (FDG) uptake has shown to be associated with concurrent inflammation. We evaluated the prognostic value of diffuse splenic FDG uptake for predicting prognosis in cholangiocarcinoma patients. Patients, methods: Sixty-four patients with unresectable cholangiocarcinoma performed Positron emission tomography/computed tomography (PET/CT) using FDG between July 2009 and April 2012. Patients were divided into two groups according to splenic FDG uptake relative to hepatic FDG uptake. Eleven patients showing splenic FDG uptake exceeding hepatic uptake were included in group A, while 53 patients with hepatic FDG uptake exceeding splenic uptake were included in group B. Prognostic factors for overall survival were evaluated using log-rank test. Variables with a probability of less than or equal to 0.1 on univariate analysis were considered as possible independent factors. Cox-proportional hazards Cholangiocarcinoma, a malignant neoplasm of biliary epithelium, is a rare disease with an increasing incidence worldwide (19). The chances of survival with cholan- giocarcinoma depend on its location and model was used to analyze univariate and multivariate analysis. Results: Mean standardized uptake value of the liver (Liver SUVmean)/ Spleen SUVmean (L/S) ratio <1 (p = 0.0034), WBC > 10 000 (p = 0.1155) and CEA >30 (p = 0.0946) were predictors of overall survival on univariate analysis. In a subsequent multivariate analysis, L/S ratio <1 remained a significant independent predictor of poor prognosis (HR 6.0153, 95% CI, 1.7193-21.0460, p = 0.0052). Conclusion: Our study has shown that splenic FDG uptake could be a predictor of overall survival of unresectable cholangiocarcinoma patients.

18F-FDG uptake in multiple splenic foci on PET/CT: an unusual case of visceral leishmaniasis

A previously well 48-year-old male patient presented with several months of weight loss, fever, massive hepatosplenomegaly, and pancytopenia. A provisional diagnosis of lymphoma could not be confirmed on blind lymph node or bone marrow biopsies. Referral for 18F-FDG PET was made to identify an appropriate biopsy site. Focal uptake in multiple splenic lesions was seen, with normal FDG uptake elsewhere in the body. Splenectomy was then performed and histology revealed leishmaniasis, with no evidence of lymphoma. Focally FDG avid splenic deposits have never been reported in leishmaniasis and were likely due to nodular red pulp expansion.

The clinical implication and prediction of diffuse splenic FDG uptake during cancer surveillance

OBJECTIVE

The purpose of this study was to investigate correlations between diffuse splenic FDG uptake and hematological and inflammatory parameters to clarify the significance of splenic FDG uptake on PET/CT images.

METHODS

We retrospectively analyzed the consecutive records of F-18 FDG PET/CT scans and selected 31 patients with diffuse splenic FDG uptake as patient group. A total of 25 patients who underwent F-18 FDG PET/CT scans for simple health checkup were enrolled as control group. ROIs were placed on the liver and spleen to measure maximal standardized uptake value (SUVmax). The spleen SUVmax was divided by the liver SUVmax to calculate the spleen/liver ratio. The correlations between the S/L ratio and various hematological parameters were evaluated.

RESULTS

The S/L ratio was positively correlated with serum C-reactive protein level, white blood cell count, and neutrophil count and negatively correlated with hemoglobin, hematocrit, and red blood cell count. Under multiple regression analysis, the Hb level and the C-reactive protein level were the significant predictors for diffuse splenic FDG uptake.

CONCLUSION

In conclusion, our study suggests that concurrent inflammation or anemia at the time of PET/CT study could be one of various causes of diffuse splenic FDG uptake.

[Vasculitis assessment with [18F]FDG positron emission tomography]

[18F]fluorodeoxyglucose positron emission tomography (PET) is a noninvasive metabolic imaging modality that is well-suited to the assessment of activity and extent of large vessel vasculitis. PET imaging has demonstrated its usefulness in diagnosing giant cell arteritis (notably in its silent form), Takayasu's arteritis, and unclassified aortitis. PET imaging could be more effective than magnetic resonance imaging in detecting the earliest stages of vascular wall inflammation. The visual grading of vascular [18F]FDG uptake makes it possible to discriminate arteritis from active atherosclerosis, providing therefore high specificity. High sensitivity can also be achieved provided scanning is performed during active inflammatory phase, preferably before starting corticosteroid treatment. Prospective studies are needed to determine the exact value of PET imaging in assessing other vasculitis subsets, infectious aortitis, and large vessel vasculitis outcome and response to immunosuppressive treatment.

Wegener's granulomatosis detected initially by integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography

Early diagnosis is crucial for effective treatment of Wegener's granulomatosis, although this disease shows only atypical symptoms in the primary stage. This report describes a patient suspected of having a malignancy based on integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT), which showed increased uptake in pulmonary nodules and nasopharyngeal mucosa. Integrated PET/CT is therefore considered to be useful to confirm the distribution and determine the optimal site for biopsy.