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.

Hyalinizing trabecular tumor in a background of lymphocytic thyroiditis: a challenging neoplasm of the thyroid.

OBJECTIVE: To describe a case of hyalinizing trabecular tumor (HTT) in a background of lymphocytic thyroiditis that was misdiagnosed as papillary thyroid carcinoma (PTC) based on fine-needle aspiration (FNA) cytologic findings and overtreated with total thyroidectomy. METHODS: We present a case report, including the imaging and pathologic findings, of a 68-year-old woman who presented with a multinodular goiter that was suspicious for PTC. RESULTS: On the basis of FNA cytologic findings, she underwent a total thyroidectomy, and histologic examination of the thyroid gland revealed HTT in a background of lymphocytic thyroiditis. Radioiodine treatment was not administered because of the tumor's low risk profile. No metastatic foci were established under nonsuppressive levothyroxine therapy after 3 years of follow-up. CONCLUSIONS: HTT is a challenging entity because of the uncertainty of its nature, the diagnostic challenges, and the mimicry of other types of thyroid tumors. In order to avoid overtreatment, endocrinologists and thyroid surgeons should be aware of the features of HTT, and suspicious cases should be evaluated by experienced cytopathologists.

Ovarian hilus-cell hyperplasia and high serum testosterone in a patient with postmenopausal virilization.

OBJECTIVE: To describe a woman with postmenopausal virilization and hirsutism caused by hilus-cell hyperplasia. METHODS: We present a case report including laboratory, radiographic, and pathologic findings in a patient with postmenopausal hirsutism and virilization caused by ovarian hilus-cell hyperplasia as well as a brief review of the literature. RESULTS: A 60-year-old postmenopausal woman presented with extensive hirsutism, male-pattern hair loss, and clitoromegaly. The patient's plasma testosterone levels were very high, but computed tomography showed the adrenal glands to be normal in size. Pelvic ultrasonography revealed a cystic lesion in the left ovary. After bilateral salpingo-oophorectomy, histologic examination demonstrated a diffuse pattern of hilus-cell hyperplasia in the ovarian hilum. CONCLUSION: In the differential diagnosis of postmenopausal virilization, hilus-cell hyperplasia, although rare, should be considered.

Effects of alendronate sodium therapy on carotid intima media thickness in postmenopausal women with osteoporosis.

Osteoporosis and cardiovascular disease are major health problems that lead to morbidity and mortality. Bisphosphonates are among the drugs used most frequently worldwide to treat osteoporosis, especially in older women. B-mode ultrasonography has recently become a valuable tool for early diagnosis of atherosclerotic disease because of its ability to measure carotid artery intima media thickness (CIMT). The purpose of the present study was to investigate whether alendronate sodium therapy has an effect on CIMT in postmenopausal women with osteoporosis. A total of 71 postmenopausal women with osteoporosis were evaluated before and after they began taking alendronate sodium; follow-up was provided for an average of 13+/-2 mo. Osteoporosis was diagnosed with the use of dual-energy x-ray absorptiometry, and therapy with alendronate sodium was begun at a dose of 70 mg/wk. For CIMT, B-mode ultrasonography was performed on the right and left middle and distal main carotid arteries. Before alendronate sodium therapy was initiated, the average CIMT value was 0.734+/-0.121 mm; after therapy, the average CIMT was 0.712+/-0.111 mm. This difference was not confirmed to be statistically significant. Treatment of osteoporosis does not seem to have an effect on CIMT, which is an early marker of atherosclerosis.

Effect of simvastatin use on bone mineral density in women with type 2 diabetes.

OBJECTIVE: To attempt to clarify the effect of simvastatin, a widely used statin, on the bone mineral density in women with type 2 diabetes. METHODS: We performed a cross-sectional, controlled study of 37 women with type 2 diabetes who were taking simvastatin. Each woman was matched with 2 control subjects who were closest in age, years since menopause (if applicable), and duration of diabetes on the date on which the examination was performed. We measured bone mineral density at the spine and the hip with a dual-energy xray absorptiometry scanner and compared bone density in the 2 study groups. RESULTS: The mean bone mineral density values of patients in the simvastatin group were found to be slightly increased in comparison with those of the control group, both in the lumbar vertebrae and in the femoral neck, but these differences were not statistically significant (P>0.05). CONCLUSION: In this cross-sectional study, we could not demonstrate a positive effect of long-term simvastatin treatment on bone mineral density in women with type 2 diabetes and hypercholesterolemia.