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Endocrine and Neuroendocrine Tumors
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
Natasha Shrikrishnapalasuriyar, P.N. Plowman, Márta Korbonits, Ashley B. Grossman
Biochemical diagnosis is based on increased catecholamine metabolites. Plasma or urinary fractionated metanephrines (normetanephrine and metanephrine) are highly sensitive and form the basis for specific screening tests that detect secretory pheochromocytomas and paragangliomas: Plasma 3-methoxytyramine, a metabolite of dopamine, is used as a potential marker of malignancy.66
Primary adrenal malignancy
Published in Anju Sahdev, Sarah J. Vinnicombe, Husband & Reznek's Imaging in Oncology, 2020
Ayshea Hameeduddin, Anju Sahdev, Rodney H Reznek
Free plasma metanephrines and 24-hour free urinary metanephrines are accurate methods for establishing diagnosis of pheochromocytoma. Their respective sensitivity and specificities range from 96%–100% and 92%–99% and 87%–92% and 64%–72%, respectively (75,76). The measurement of plasma metanephrines is easier than urinary measurements.
Pheochromocytoma and Paraganglioma
Published in Giuseppe Mancia, Guido Grassi, Konstantinos P. Tsioufis, Anna F. Dominiczak, Enrico Agabiti Rosei, Manual of Hypertension of the European Society of Hypertension, 2019
Andrzej Januszewicz, Jacques W.M. Lenders, Graeme Eisenhofer, Aleksander Prejbisz
Early postoperative follow-up is recommended and blood pressure and plasma or urinary metanephrines should be measured 1–2 weeks after the surgery. If plasma metanephrines are completely normalized after surgery, resection is considered complete. Elevated levels may indicate the presence of residual tumour, a second PPGL or metastases (1,42,52).
Clinical presentation and diagnostic evaluation of pheochromocytoma: case series and literature review
Published in Clinical and Experimental Hypertension, 2023
Panagiota Anyfanti, Κonstantinos Mastrogiannis, Αntonios Lazaridis, Κonstantinos Tasios, Despoina Vasilakou, Αnastasia Kyriazidou, Fotios Aroutsidis, Olga Pavlidou, Εleni Papoutsopoulou, Athina Tiritidou, Vasileios Kotsis, Αreti Triantafyllou, Ιoannis Zarifis, Stella Douma, Εugenia Gkaliagkousi
According to the international guidelines for the diagnosis and treatment of pheochromocytoma, the initial screening test is measurement of plasma or 24-hour urine metanephrine levels, whose diagnostic value is higher compared to the previously used urinary catecholamines or VMA (6,29). More specifically, measurement of urine metanephrines provides excellent sensitivity and specificity for the diagnosis of pheochromocytoma, reaching 97% and 91%, respectively (30). A positive biochemical screening test must be followed by imaging in order to locate the tumor. Abdominal CT with intravenous contrast infusion is suggested as the imaging examination of choice and is considered superior to magnetic resonance imaging (MRI) (6), owing to its excellent spatial analysis for the chest, abdomen and pelvis, with excellent sensitivity for tumor localization varying from 88% to 100% (31–34). MRI should be preferred over CT in exceptional cases such as patients with known allergy to intravenous contrast agents or patients whose exposure to ionizing radiation should be avoided (pregnancy, children, presence of surgical clips, need for repeated imaging as in familial syndromes) (6). However, it needs to be highlighted that both CT and MRI lack specificity for pheochromocytoma, which may present either as a homogeneous or heterogeneous mass, a necrotic mass with calcifications, or a solid or cystic tumor (3,35).
Thyroid paraganglioma – a rare entity
Published in Journal of Endocrinology, Metabolism and Diabetes of South Africa, 2023
K Naidu, V Saksenberg, MF Suliman, B Bhana
On laboratory investigations, thyroid function tests, serum calcitonin (< 0.2 ng/l [0–5]) and CEA (< 1 ng/ml [0–5]) were normal. Plasma normetanephrines analysis showed a twofold increase (plasma normetanephrines = 414 pg/ml [0–196]) with normal plasma metanephrines. Urinary fractionated metanephrines and chromogranin A were not performed. Renal function and liver function were normal. Blood tests were consistent with Hashimoto’s thyroiditis and menopause. Thyroid ultrasonography revealed a large (> 4 cm) solid hypoechoic left thyroid nodule (Figure 1) with increased peripheral and intranodal vascularity (Figure 1). The nodule had American Thyroid Association (ATA) sonographic features that were consistent with an intermediate suspicion pattern nodule (ACR-TIRADS = 4 [5 points]). Genetic testing for susceptibility genes was not available. Ethics approval was granted by the University of the Witwatersrand Human Research Ethics Committee (Ethics approval number: M200144).
The effect of acid use as a preservative on the results of biochemical tests measured in 24-h urine
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2022
Ceylan Bal, Canan Topcuoğlu, Ahmet Rıfat Balık, Fatma Meriç Yılmaz, Özcan Erel, Gülsen Yılmaz
In terms of mean percent differences for adrenaline and noradrenaline, the parameters in which acid use is recommended as a preservative, the difference between groups B and E from group A was greater than the difference between groups C and D (although the difference between groups B and E for adrenaline was less than 10%). Willemsen et al. found low varying concentrations of adrenaline in 3 of 8 samples and noradrenaline in 4 of 8 samples stored at room temperature without preservatives after 24 h [21]. In other studies in the literature, it was reported that the catecholamine concentration decreased within 24 h. Most of these studies are studies conducted with a limited number of individuals or by creating a urine pool [22–24]. The limited number of studies evaluating metanephrines found no significant difference in metanephrine concentrations in treated and untreated samples [11,21,25]. In our study, there was no significant difference in all of the other groups when compared with the group that we accepted as a reference.