The efficacy of fluorine-18-choline PET/CT in comparison with 99mTc-MIBI SPECT/CT in the localization of a hyperfunctioning parathyroid gland in primary hyperparathyroidism.

AIM: The aim of this study was to determine the role of fluorine-18-choline (F-FCH) PET/CT in comparison with technetium-99m-methoxyisobutylisonitrile (Tc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) in primary hyperparathyroidism and to investigate whether maximum standardized uptake value (SUVmax) may be indicative of disease severity. PATIENTS AND METHODS: Thirty-five primary hyperparathyroidism patients (24 females, 11 males, mean age: 55.31±12.27, range: 25-72 years) who underwent Tc-MIBI SPECT/CT and F-FCH PET/CT and had inconclusive neck ultrasonography (USG) were studied. The diagnostic power of both modalities and the relationship between SUVmax and biochemical [serum parathormone (PTH), calcium, phosphorus, vitamin D3 levels, urinary calcium excretion/24 h] and clinical (bone mineral densitometry and urinary USG results) parameters were analyzed. RESULTS: In 29 of 35 patients, Tc-MIBI SPECT/CT and F-FCH were concordant (κ=0.64, P=0.001). In five of 35 patients with a negative SPECT/CT, F-FCH PET/CT accurately localized parathyroid adenomas. In one patient, F-FCH was false negative and Tc-MIBI SPECT/CT showed the lesion. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of Tc-MIBI SPECT/CT and F-FCH PET/CT were calculated to be 78, 100, 100, 70, 86%, and 96, 100, 100, 93, and 97%, respectively. SUVmax was correlated with lumbal T scores (P=0.026). The mean serum PTH levels were significantly higher (P=0.026) and lumbal and femur T scores were significantly lower (P=0.04 and 0.008) in patients with SUVmax greater than 4.4 (i.e. the mean SUVmax calculated in positive cases). CONCLUSION: F-FCH PET/CT has a high diagnostic power in primary hyperparathyroidism and can be used for further evaluation of patients with inconclusive neck USG and Tc-MIBI SPECT/CT. SUVmax of the hyperfunctioning parathyroid gland seems to be predictive of disease severity in terms of serum PTH and bone mineral densitometry results. Studies with larger patient groups are needed to support these data.

Prognostic factors for prediction of survival of hepatocellular cancer patients after selective internal radiation therapy.

AIM: In this study, it was aimed to explore the prognostic factors in patients who received selective internal radiation therapy for hepatocellular cancer. MATERIALS AND METHODS: A retrospective evaluation was made of 28 (24 male, 4 female, mean age 65.4 ± 6.8 years) hepatocellular cancer patients who received selective internal radiation therapy with Y-90 resin microspheres. Using Cox proportional hazards regression analysis, the relationship between age, gender, MELD score, serum albumin and AFP levels, number of liver lesions, size of the largest lesion, absence of (18)F-FDG uptake, maximum standardized uptake value and overall survival times was analyzed. RESULTS: Treatment was applied to the right lobe in 22 and both in 6 patients. Mean treatment dose was 1.5 ± 0.2 GBq. Number of liver lesions were 1, <5 and multiple in 16, 5 and 7 patients, respectively, and the mean size of the largest lesion was 41.5 mm (min-max 15-160 mm). While (18)F-FDG uptake was seen in 24 patients, liver lesions were hypometabolic in 4 patients. Mean SUVmax of liver lesions was calculated as 5.3 ± 0.3. During the mean 17.8 (min-max 2-39) months follow-up period, 19 patients died. Median survival time was computed as 18 ± 5 months (95% CI 8.1-27.8). Age (p = 0.04), serum AFP level (p = 0.03) and size of the largest lesion (p = 0.02) had a significant negative effect on survival according to the Cox proportional hazards regression analysis. CONCLUSION: Age, serum AFP level and the size of the largest liver lesion have a negative significant effect on survival of hepatocellular cancer patients who received selective internal radiation therapy.