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.

SURVIVIN POSITIVITY AND PROGNOSTIC FACTORS IN PAPILLARY THYROID CARCINOMAS

CONTEXT

Papillary thyroid carcinoma(PTC)s are the indolent progressive tumours. Survivin is a unique bifunctional protein with cell cycle regulation and apoptosis inhibition. The expression of this protein has been shown to be increased in thyroid tumours correlated with aggressive behavior from well differentiated to anaplastic.

OBJECTIVE

In this study, we aimed to investigate the relationship between immunohistochemically survivin expression and tumour-associated prognostic factors in papillary thyroid carcinomas.

DESIGN

In patients with thyroidectomy, we compared the clinicopathological findings and immunohistochemical positivity for survivin.

SUBJECTS AND METHODS

In 109 patients, sex, age, tumour size, histological tumour variant, tumour focality, tumour border pattern, tumour peripheral/intratumoural lymphocytic and stromal response, intraglandular spread, extrathyroideal spread, lymph node metastases, lymphocytic tiroiditis and relationships of these findings with survivin positivity were investigated.

RESULTS

When we indicated the tumour size and compared it with survivin expression, tumour size correlates with, survivin expression (p = 0.016). Survivin expression was correlated statistically significant with lymphovascular invasion, without stromal response and with intraglandular extension respectively (p<0.001, p = 0.043, p<0.001). No significant correlation was found between other clinicopathological parameters and survival.

CONCLUSION

Few studies have investigated the relationship of survivin expression with prognosis in thyroid papillary carcinomas and showed that survivin was a poor prognostic marker. If its expression is detected in preoperative cytology smears, it may affects the surgical treatment strategy. When it is detected in the tissue, postoperative radioactive iodine treatment plan may be modified and the need for more aggressive follow-up may be considered.

Tumor characteristics of lung cancer in predicting axillary lymph node metastases

OBJECTIVE

In lung cancer, axillary lymph node metastases (ALM) are rare, and according to the 8th grading system, it is classified as M1b disease. The aim of this study is to evaluate1) the presence of ALM and2) the effect of the primary tumors characteristics on the development of ALM.

METHODS

We performed a descriptive cross-sectional study, with retrospective revision, to identify ALM.

RESULTS

There were 157 patients included in this analysis: ALM (63 patients) and control group (94 patients). The presence of extrathoracic lymph node, contralateral pulmonary parenchymal and distant metastasis and all SUVmax values were significantly higher in the study group versus the control group (P<0.05). The SUVmax value of the primary tumor was not a predictor of ALM. According to the primary histopathologic diagnosis, small cell lung cancer was found to cause ALM development 3.4 times as much as squamous cancer (SQC) (OR: 3.40 [95% CI 1.3-10.20], P=0.029) and adenocarcinoma group was found to cause ALM development 4 times as much as SQC (OR: 4.02 [95% CI 1.73-9.34], P=0.001). The likelihood of developing ALM was significantly higher in tumors located in the central and upper lobe versus the lower lobe.

CONCLUSION

The finding of ALM on PET/CT images, the necessity of histopathologic confirmation is determined according to the results of primary tumor localization, primary tumor histopathology, M stage on PET/CT imaging, localization of ALM according to primary tumor, and N stage on PET/CT imaging.