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.

A RARE CLINICAL PRESENTATION: A PATIENT WITH CHRONIC RENAL FAILURE, SECONDARY HYPERPARATHYROIDISM AND CALCIPHYLAXIS.

Calciphylaxis, also known as calcific uremic arteriolopathy (CUA), is usually observed in women and it is a serious complication of hyperparathyroidism secondary to chronic renal failure. CUA is characterized by ischemic tissue loss secondary to progressive vascular degeneration. Although it is rare, it may end up with sepsis and organ failure and can be fatal. Its pathogenesis is not fully understood, but it is thought that it occurs secondary to increased calcification activators such as oxidized LDL, TNF- α, calcitriol, fibronectin, collagen-I, and TGF-1α. The most effective treatment is managing underlying pathology and decreasing serum calcium and phosphorus levels. In this report, we aimed to present an end stage renal failure case with coexisting hyperparathyroidism, hyperthyroidism and calciphylaxis in whom cutaneous manifestations were healed 6 months after parathyroidectomy.

CLINICALLY UNDETECTABLE OCCULT THYROID PAPILLARY CARCINOMA PRESENTING WITH CERVICAL LYMPH NODE METASTASIS.

BACKGROUND: Occult papillary thyroid carcinoma presented as isolated cervical lymphadenopathy without clinical and radiologic findings has been rarely reported. CASE REPORT: A 47 years old female patient admitted to otorhinolaryngology clinic with 4X3 cm sized cervical mass. Physical examination of the patient was noted as a nontender, firm, mobile lymph node at right lateral cervical region. There was no inflammatory or infection disease in the history of patients anamnesis and no abnormal value on laboratory tests. Ultrasound screening of the neck detected a lymph node with suspicious features for malignancy. Head and neck examination was normal and there is no evidence of a tumoral mass or nodule in the thyroid gland. Whole body scan of MRI showed no pathologic sign both in the neck and body. Excisional biopsy was performed and revealed a carcinoma with papillary morphology. Immunohistochemical staining features of the tumor confirmed a papillary carcinoma derived from the thyroid gland. Second look USG of the neck and thyroid was performed but it revealed no tumoral mass. The patient underwent total thyroidectomy with right functional and central lymph node dissection. Histological examination of the thyroid gland showed multicentric 2 mm sized, three foci of papillary carcinoma located in bilateral thyroid lobes and metastatic lymph nodes in the right side of the neck. CONCLUSION: A metastatic cervical lymph node can be evidence of a clinically undetected occult papillary thyroid carcinoma. Specific immunohistochemistry staining of specimen may lead to appropriate surgery and progression of carcinoma may be hindered by application of additional RAI therapy.

Unresectable huge sternal and mediastinal metastasis of follicular thyroid carcinoma; radiotherapy as first-line and palliative therapy.

Distant metastases as initial manifestation of follicular thyroid carcinoma is rare. We report a case of an unusual initial presentation of follicular thyroid carcinoma on follow-up. A 52- year-old woman presented with a 12-month history of progressively enlarging mass in the anterior chest wall. The mass was fixed to the chest wall, measuring 12 x 10 cm in diameter. Computed tomography demonstrated a lobulated soft-tissue mass (17 x 11 x 6 cm) destructing sternum and extending into the anterior mediastinum. There was no lung metastasis. Invasion of tumor to the ascending aorta, superior vena cava, and right atrium could not be excluded. Multiple lymph nodes were observed in the supraclavicular regions. Ultrasonography of the thyroid gland showed 46 x 37 mm nodule in the left lobe with milimetric gross calcifications and cystic-necrotic areas. Hyperthyroidism was detected. Biopsy from this nodule and the sternal mass revealed typical histology of follicular carcinoma. She was considered inoperable. Since there was huge tumor burden and iodinated contrast exposure for several times during evaluation, we decided to treat the patient with external beam radiotherapy (EBRT) rather than radioiodine as first-line therapy. After a course of conventional radiation with 50 Gy in 25 fractions over 4 weeks, encompassing the thyroid bed and the gross disease, tumor regressed remarkably in 6 months. In conclusion, when surgical resection is not possible, EBRT may be used for palliative purpose to obtain local control for extensive disease as first-line therapy. The indications of EBRT for differentiated thyroid cancer still remain poorly defined.

Polycythemia as the first manifestation of Cushing's disease.

A 39-yr-old man presented to our hospital with unexplained erythrocytosis and hypertension. His follow-up for erythrocytosis had begun 2 yr earlier in another hospital and he had been diagnosed with polycythemia rubra vera. On admission to our hospital he was hypertensive (165/95 mmHg) and, except for the presence of moon-like face and facial plethora, his physical examination was normal. His hemoglobin concentration was 19.2 g/dl, and hematocrit was 58.9% with an increased red blood cell mass of 58 ml/kg as measured by radioisotope (Cr51). Blood film, other hematological indices except for elevated leukocyte alkaline phosphatase score, arterial gas analysis, and examination of aspirated bone marrow were all normal. An abdominal ultrasonography showed no evidence of splenomegaly. A diagnosis of probable secondary erythrocytosis was made. Early-morning serum cortisol and 24-h urinary free cortisol concentration as well as serum ACTH were high. Serum cortisol was not suppressed by low-dose dexamethasone, but suppressed by high-dose dexamethasone. Pituitary magnetic resonance imaging showed no lesion. After inferior petrosal sinus sampling suggesting right-central ACTH secretion, the patient underwent transnasal-transsphenoidal pituitary adenomectomy. Both hypercortisolemia and erythrocytosis regressed completely after the adenomectomy. After the operation, the patient's hemoglobin concentration and hematocrit decreased steadily, and 1 month post-adenomectomy his hemoglobin is 14.9 g/dl and hematocrit 44.8%. Thus, Cushing's syndrome should be a routine part of evaluation of unexplained polycythemia.