Thyroid pathologies and non-medullary thyroid cancer often accompany primary hyperparathyroidism (PHPT). The purpose of this study was to examine the association between thyroid diseases, especially micropapillary thyroid cancer, with PHPT. Data regarding 46 patients who were operated on with a diagnosis of PHPT at Inonu University Faculty of Medicine, General Surgery Clinic between June 2009 and March 2013 were retrospectively analyzed. Age, gender, levels of preoperative calcium, parathyroid hormone and phosphorus, and the histopathological results of the removed parathyroid and thyroid tissues were evaluated. All of the patients had a preoperative diagnosis of PHPT and there was no history of radiation to the head and neck region in any of the patients. Out of the 46 patients who were operated on for PHPT, 39 were female and 7 were male. The mean age was 52.8 years (25-76). Simultaneous thyroidectomy was performed in 35 patients (76.1%) due to an accompanying thyroid disorder. Papillary microcarcinoma was detected in 5 of these 35 (10.9%) patients who underwent thyroidectomy, two of which (40%) were multifocal tumors. The benign thyroid pathologies detected in the remaining 30 (65.2%) cases included lymphocytic thyroiditis in 3, Hashimoto thyroiditis in 1, follicular adenoma in 3 (two of which was Hurtle cell), and nodular colloidal goiter in 23 patients. The preoperative serum phosphate level was significantly higher in the group with papillary thyroid microcarcinoma (p=0.013). In regions where goiter is endemic, thyroid diseases and thyroid papillary microcarcinoma occur in association with PHPT at a higher rate compared to the normal population. Therefore, we believe that patients who are planned for surgery due to PHPT should be thoroughly investigated for the presence of any concomitant malignant thyroid pathologies in the preoperative period. It should also be kept in mind that patients with high blood serum phosphate values may have an increased risk of papillary thyroid microcarcinoma.

Background and Aim: There are conflicting results of studies on accuracy of positron emission tomography (PET)/computed tomography (CT) for axillary staging. The aim of this study is to determine the factors affecting the efficacy of 18F-fluorodeoxyglucose (¹⁸F-FDG) PET/CT in detecting axillary metastases in invasive breast cancer. Materials and Methods: Data of 232 patients with invasive breast cancer who underwent ¹⁸F-FDG PET/CT examination before surgery between January 2013 and September 2017 were reviewed retrospectively. Histopathological examination of axillary lymph nodes (ALNs) was used as a reference to assess the efficacy of ¹⁸F-FDG PET/CT in detecting axillary metastases. Results: While 134 (57.8%) patients had axillary metastases as detected in ¹⁸F-FDG PET/CT scans, histopathologically axillary metastases were detected in 164 (70.7%) patients. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of ¹⁸F-FDG PET/CT in detection of axillary metastasis were 72.56%, 77.94%, 88.8%, 54%, and 74.1%, respectively. The false-negative and false-positive rates were 27.4% and 22%, respectively. In univariate analysis, patients' age, estrogen receptor positivity, higher ALN SUVmax, greater tumor size, and lymph node size determined by ¹⁸F-FDG PET/CT were all significantly associated with accuracy of ¹⁸F-FDG PET/CT for axillary metastasis. In multivariate analysis, tumor size determined by ¹⁸F-FDG PET/CT and ALN SUVmax were independent variables associated with axillary metastasis. The accuracy of ¹⁸F-FDG PET/CT for axillary metastasis was higher in patients with a larger tumor (≥19.5 mm) and a higher ALN SUVmax (≥3.2). Conclusion: ¹⁸F-FDG PET/CT should not be routinely used for axillary staging, especially in patients with small tumors. It cannot eliminiate the necessity of sentinel lymph node biopsy. When it is used, both visual information and optimal cut-off value of axillary node SUVmax should be taken into consideration.