ABSTRACT
ABSTRACT Objective: Although 18F-sodium fluoride (18F-NaF) uptake is frequently observed in extraosseous metastases of medullary thyroid carcinoma (MTC) with calcification, it can also occur in metastatic sites without visible calcium deposition, leading to the hypothesis that visually undetectable calcium accumulation may be responsible for this uptake. The aim of this study was to indirectly support this hypothesis by analyzing the correlation between the degree of 18F-NaF uptake and radiodensity in extraosseous MTC metastases, since calcium deposition can increase attenuation even when not visually detectable. Subjects and methods: Extraosseous metastatic lesions of 15 patients with MTC were evaluated using 18F-NaF positron-emission tomography (PET)/computed tomography (CT) and segmented by levels of standardized uptake value (SUV). The correlation between mean SUV and mean Hounsfield unit (HU) values was assessed for the entire group of segments and for two subgroups with different mean HU values. Results: Very high correlations were observed between mean SUV and mean HU values for both the entire group of segments and the subgroup with a mean HU value greater than 130 (p = 0.92 and p = 0.95, respectively; p < 0.01). High correlation (p = 0.71) was also observed in the subgroup with mean HU values ranging from 20 to 130 (p < 0.01). Conclusion: The findings of the present study suggest that there is an association between 18F-NaF uptake and calcium deposition in extraosseous metastases of MTC, supporting the hypothesis that visually undetectable calcium accumulation may be responsible for 18F-NaF uptake in regions without visible calcium deposition.
ABSTRACT
The present study aimed to assess the diagnosis, treatment and follow-up of uterine sarcoma cases. A retrospective cohort study with 122 women recruited between 2001 and 2016 was performed. The data regarding epidemiology, clinical presentation, treatment and follow-up were analyzed based on the following histological types: Carcinosarcoma, leiomyosarcoma, endometrial stromal sarcoma (ESS) and adenosarcoma. Statistical analysis included descriptive statistics, logistic regression and survival curves. The diagnosis of uterine sarcoma exhibited an increasing trend of +1.2 new cases every 2 years (P=0.044) and comprised 10% of all uterine cancer diagnoses. There were 47% carcinosarcomas, 22% leiomyosarcomas, 16% ESS and 14% adenosarcomas. The majority of the women was ≥60 years old (62%). Among the subjects, 77% were postmenopausal, 61% had a body mass index up to 29.9 kg/m2 and 71% presented with a comorbidity. Regression analysis exhibited an association between post menopause and the histological type associated with lower overall survival (OS), namely leiomyosarcoma or carcinosarcoma (odds ratio, 5.45, P<0.001). Stage I malignancy was present in 44% and Stage IV in 22%. The treatment included primary surgery in 78% of the cases, whereas 79% received adjuvant therapy. Only 55 cases achieved disease control and 20 relapsed (36%) with a 5-year OS rate of 33%. The OS was lower for carcinosarcoma and leiomyosarcoma (20%; P=0.003). In summary, the present study indicated that the number of uterine sarcoma cases had increased between 2001 and 2016. The majority of the women were >60 years old and diagnosed in advanced stages. The postmenopausal status was associated with histological types of poor prognosis. The OS was low and worse for patients with carcinosarcoma and leiomyosarcoma.
