PAGET'S DISEASE OF THE BONE FOUND INCIDENTALLY ON F-18 FDG PET/CT: CLINICAL SIGNIFICANCE AND DIFFERENTIAL DIAGNOSTIC CRITERIA

Background

Paget Disease (PD) is usually asymptomatic and discovered incidentally, it is known that it is exhibited low to high grade increased F-18 FDG uptake.

Aim

In this study, we investigated the distinguishability of FDG PET/CT in incidental PD cases from other bone diseases and at different stages of the disease.

Patients and Methods

In this cross-sectional, descriptive study, "Paget" identification associated with PET/CT reports was found in 69 of 18,119 studies (~3.8%). Of the 45 patients (33 males and 12 females) eligible for inclusion in the study, 35.6% had monostotic and 64.4% had polyostotic disease (p>0.5). There was no statistically significant difference in biochemical parameters between groups.

Results

According to the radiological appearance of the patients, 36 were in the mixed stage and 9 were in the blastic stage. Only the difference in ALP and creatinine values between the groups was statistically significant. SUVmax, SUVmean and HU values were found to be statistically significantly higher in pagetoid bones compared to control bone lesions. For SUVmax for PD bone lesion we found the 2.55 cutoff point with a sensitivity of 91% and a specificity of 84%.

Conclusion

The specific radiological appearance of bone lesions and the evaluation of metabolic activity compared to normal bone seem to help differentiate PD from other lesions. Prospective studies are needed in the differentiation of FDG's disease stage and treatment response evaluation. The ability to differentiate between benign and malignant FDG avid bone lesions in oncological patients' enables appropriate patient management, including avoiding unnecessary additional invasive procedures such as bone biopsy.

Clinical and demographic aspects of Paget disease of bone: A multicentric study from Turkey

OBJECTIVE

Paget disease of bone (PDB) is a metabolic bone disease that has been rarely reported in the Eastern countries. This study aimed to evaluate the clinical and demographic characteristics of patients with PDB followed up at endocrinology clinics in Turkey.

METHODS

An invitation was sent to tertiary endocrinology clinics to complete a survey on the demographic, clinical, radiological, and laboratory parameters, as well as treatment modalities of patients with PDB. This study enrolled clinically and radiologically proven 185 patients with PDB from 18 endocrinology centers based in 10 cities of Turkey.

RESULTS

This cohort of PDB had female preponderance (women/men: 105/80) with a mean age, during diagnosis, of 57±10 years. Most of the patients (59.6%) were symptomatic at diagnosis. Bone pain and headache were the predominant clinical symptoms. Polyostotic disease was observed in 67.5% (n=125) of patients. Frequently affected bones were skull (41.6%), pelvis (53.5%), spine (41%), and femur (25.4%). Moreover, 17 patients with skull involvement had hearing loss. Mean serum alkaline phosphatase (ALP) level (552±652 IU/L; range: 280-5762 IU/L) was over the normal reference cutoff with normal serum calcium levels. Intravenous bisphosphonates (zoledronic acid, 5 mg; pamidronate, 60-90 mg) were the most used drugs (75%) for the treatment of PDB. Most of the patients (87.1%) treated with intravenous bisphosphonates responded well, with a decrease in serum ALP level (117±114 IU/L) in the 12th month of therapy. Furthermore, 16 patients relapsed after the second year of therapy; 3 patients did not respond to the initial intravenous bisphosphonate treatment.

CONCLUSION

The patients with PDB followed up by endocrinology clinics of Turkey exhibited polyostotic disease with classical clinical, radiological, and biochemical features and women's predominance with good response to intravenous bisphosphonate therapy.

TERT Expression in Pituitary Adenomas

OBJECTIVE

Although pituitary adenomas have benign histomorphological features, some of them may present in an aggressive manner. To predict the behaviour of these tumours, telomerase reverse transcriptase (TERT) activity in pituitary adenomas has been the subject of a few studies with contradictory results. This study aims to investigate whether immunohistochemical expression of TERT differs in neoplastic and nonneoplastic pituitary tissues and aims to investigate whether TERT expression is related to clinicopathological features of pituitary adenomas.

MATERIAL AND METHOD

The study included 48 patients who had been diagnosed with pituitary adenomas and had clinical follow-ups. Nonneoplastic pituitary tissues were obtained from autopsy specimens (n=20). Immunohistochemistry for TERT antibody was performed. Both the nuclear and cytoplasmic expression of TERT antibody was noted, and total combined TERT staining was evaluated according to nuclear and cytoplasmic stainings.

RESULTS

TERT expression did not differ between neoplastic and nonneoplastic pituitary tissues. Neither total (combined nuclear and cytoplasmic) TERT nor nuclear TERT expression revealed any statistically significant relationship with any of the clinicopathological features. Higher cytoplasmic TERT expression was observed in adenomas with recurrence than adenomas without recurrence (p=0.035).

CONCLUSION

This study introduces the notion that immunohistochemical expression of TERT does not differ in neoplastic and nonneoplastic pituitary tissues. Pituitary adenomas with cytoplasmic immunohistochemical expression of TERT have significantly higher rates of recurrence. Further studies, including combined methods of immunohistochemistry and molecular analyses in larger groups, may reveal applicable results for the clinical significance of TERT in pituitary adenomas.

Effects of raloxifene on platelet functions in patients with postmenopausal osteoporosis

Many studies have addressed the effects of estrogenic compounds on platelet function. Raloxifene is a selective estrogen receptor modulator (SERM), which is currently used for the treatment of postmenopausal osteoporosis. At present, there are no clinical data about the effects of raloxifene on platelet function. The purpose of this study was to determine if raloxifene at therapeutic doses affects platelet function in patients with postmenopausal osteoporosis. The effects of raloxifene on platelet function were investigated using a commercial platelet function analyzer (PFA-100) with collagen epinephrine and collagen adenosine 5'-diphosphate (ADP) cartridges. We studied platelet function of 30 patients with postmenopausal osteoporosis before and 15 days after initiation of raloxifene 60 mg/daily. Closure times did not differ significantly between samples obtained before (117.8 +/- 20.5 s) and after raloxifene therapy (106.5 +/- 25.4 s) in collagen/epinephrine cartridges (P > 0.05). There was also no statistically significant difference in mean closure times with collagen/ADP cartridges at baseline (86.2 +/- 18.5 s) and after raloxifene therapy (84.4 +/- 13.8 s) (P > 0.05). Platelet counts (278.3 +/- 72.9 vs. 262.4 +/- 56.7 109/L, P > 0.05) and mean platelet volumes (8.9 +/- 1 vs. 9.1 +/- 1 fL, P > 0.05) were not different before and after raloxifene therapy. Although estrogen related compounds do affect platelet function, there is suggestive data in our study that raloxifene in therapeutic dose exhibit no effect on platelet function in patients with postmenopausal osteoporosis.