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Right tympanic PGL in a 23-year-old man. (a) Axial CT image (bone window) shows softtissue-attenuation bulging of the tympanic membrane (arrow). (b) Axial nonenhanced T1-weighted MR image shows an avidly enhancing tumor (arrow) in the right middle ear.
Source publication
Pheochromocytoma (PC) and paraganglioma (PGL) are rare neu- roendocrine tumors that occur throughout the body from the base of the skull to the pelvis. Sympathetic catecholamine-secreting tu- mors may be associated with hyperadrenergic symptoms and long- term morbidity if they are untreated.Typically biochemically silent, head and neck PGLs may res...
Context in source publication
Context 1
... PGLs (Fig 6) arising from the tympanic branch of the glossopharyngeal nerve (Jacobson nerve) and the auricular branch of the vagus nerve (Arnold nerve) are the commonest tumor of the middle ear and typically manifest with pulsatile tinnitus, conductive hearing loss, and vertigo. Similar to jugular tumors, they can be locally aggressive, with destruction of the temporal bone resulting from spread by means of mastoid air cells. ...
Citations
... This pathway has been the subject for the development of many new targeted therapies. occur in more than 90% of patients with SDHD mutations, and multifocal disease occurs most commonly in patients with these mutations compared with those having mutations in other SDH subunits (Fig 9) (123). ...
... To date, a considerable progress has been made in the study of functioning of complexes (I, II, III, IV) of the electron-transport chain as sensors of apoptotic cell death and the role of their dysfunction in various pathologies. For example, it was shown that inhibition of respiratory chain complex II upon binding of the TRAP1 (tumor necrosis factor receptor associated protein 1) mitochondrial chaperone protein to succinate dehydrogenase induces oncogenesis through the formation of a pseudohypoxic state [81,82], while a decrease in the enzymatic activity of this complex accompanies tumor growth in the case of paraganglioma [83], feocromocitoma [84], and other types of malignant growth [85,86]. In turn, targeting the electron transport chain and, as a consequence, stimulation of cell death in a specific way was found for compounds of various chemical structure and therapeutic purpose. ...
A final review of the results of studies of versatile biological activities (in vitro) of chiral metal complexes with benzylamine and ethylenediamine derivatives of terpenes is presented. The cytotoxic profiles of palladacycles containing a Pd-C bond and palladium and zinc chelate complexes were determined. For a number of compounds, the possible mechanisms of potential anticancer action were analyzed, such as modulation of mitochondrial functioning and effect on the parameters of glycolytic function of tumor cells. The antibacterial and antifungal activities of palladium complexes of different types and copper chelate complexes were investigated. A correlation between high antimicrobial activity and antioxidant properties was found for a number of copper complexes. The material is supplemented by an extended analysis of publications in relevant subjects.
... Boys are typically affected more than girls (1,2). Sympathetic paragangliomas, such as that in this scenario, are believed to originate from paravertebral aorta sympathetic ganglia (3) and are located along the sympathetic chains in the thorax and abdomen (4). Twenty percent of sympathetic paragangliomas are malignant (5). ...
... Over 80% of cases of paragangliomas in children are inherited, and more than 20 genes have been implicated in their pathogenesis (6). Depending on the tumor's size, location, and biochemical activity (3,7), the clinical manifestations of sympathetic paragangliomas may include hypertension, palpitations, migraines, syncope, excessive perspiration, anxiety, and pallor. Approximately 70% of pediatric cases involve persistent hypertension (7). ...
... Subsequent CT of the chest, abdomen, and pelvis and MRI studies showed a significant (16.9 3 11.5 cm) invasive mass protruding within the hemithorax, involving the T6 and T7 vertebral bodies with nearly complete loss of height in both vertebrae, alongside a midline mass in the lower abdomen (13.7 3 10.3 cm) with marked vascularity (Figs. [2][3][4]. ...
Pheochromocytoma and paraganglioma are rare in children, at only 1 in every 50,000 cases. Even though some cases are sporadic, they have been connected to syndromes such as von Hippel-Lindau, multiple endocrine neoplasia types IIa and IIb, neurofibromatosis type 1, and hereditary pheochromocytoma-paraganglioma syndromes. A genetic mutation causes around 60% of pheochromocytomas and paragangliomas in children under 18. Methods: A 15-y-old child with a 6-y history of back discomfort is presented. The justification for using 2 functional imaging modalities, 68Ga-DOTATATE PET/CT and 123I-meta-iodobenzylguanidine SPECT/CT, is examined in this case study. We reviewed the patients' journey since the first referral for imaging. Results: Delaying the molecular imaging modalities has affected patients' overall diagnosis and applied treatment outcomes. Conclusion: This case study investigates the potential for the earlier use of various diagnostic modalities in conjunction with diagnostic testing to facilitate an earlier diagnosis. However, since this study is based solely on imaging and lacks access to the patient's clinical or family history, factors such as potential inequities in health-care facilities, health literacy, and socioeconomic status are not addressed. It is essential to acknowledge these influences as they contribute to the inequitable access to health-care settings in New Zealand.
... 32 At present, signifi cant progress has been made in the study of the functioning of electron transport chain complexes as sensors of apoptotic cell death, as well as the role of their dysfunction in various pathologies. For example, it has been shown that the inhibition of complex II of the respiratory chain due to binding of the mitochondrial chaperone TRAP1 (tumor necrosis factor receptor associated protein 1) by succinate dehydrogenase induces oncogenesis through the formation of a pseudohypoxic state, 33,34 and a decrease in the enzymatic activity of this complex accompanies the growth of tumors of paraganglioma, 35 pheochromocytoma, 36 and other malignant neoplasms. 37,38 Intracellular parasites, in particular, E. tenella, P. falciparum, are characterized by aberrant activity of mitochondrial complexes, and, as a result, their improved respiratory capacity. ...
Six new chiral zinc(ii) complexes 1–6 based on ethylenediamine derivatives of terpenes were synthesized and characterized. The molecular structure of complex 2 was established by X-ray diffraction analysis. The modulating effect of complexes 1–6 on the functional state of mitochondria, which are organelles playing an utterly important role in maintaining the energy balance of cells, transfer of genetic material, and regulation of the processes of triggering the cell death by apoptosis, autophagy, and necrosis, was studied. It is shown that synthesized zinc complexes lead to depolarization of the mitochondrial membrane, an increase in the threshold of sensitivity of the organelles to calcium-induced opening of the mitochondrial permeability transition pores, and disruption of the operation of the respiratory chain complexes in these organelles. Such a dysfunctional state of mitochondria is one of the main causes of cell death through apoptosis due to the release of various proapoptotic factors into the intracellular space. In this regard, the newly synthesized zinc complexes 1–6 can be considered as destructive agents aimed at triggering cell death cascades by affecting mitochondrial functions. These properties are of paramount importance when searching for potential drugs with possible antitumor, antiprotozoal, or antifungal activity.
... PHEP/PGL are identifiable in various types of hereditary syndromes including well-known conditions like multiple endocrine neoplasia (MEN]. syndrome type I and IIA, type 1 neurofibromatosis (NF1), Von Hipple Lindau disease (VHL) [10]. Somatic mutations are mainly related to succinate dehydrogenase (SDH) gene, generally considered to be involved in 25% of all cases with PHEO-PGL syndrome [10,11]. ...
... syndrome type I and IIA, type 1 neurofibromatosis (NF1), Von Hipple Lindau disease (VHL) [10]. Somatic mutations are mainly related to succinate dehydrogenase (SDH) gene, generally considered to be involved in 25% of all cases with PHEO-PGL syndrome [10,11]. The percent of metastatic PHEO/PGL is 8% of sporadic cases and 20-75% of patients with hereditary syndromes [1]. ...
... Paragangliomas can be visualized on MRI as heterogeneously enhancing tumors with flow voids or "salt-and-pepper" signal appearance, [3][4][5] while schwannomas can present as heterogeneously enhancing tumors with cystic change or dumbbell-shaped appearance. 6,7 However, these imaging findings are not specific and can overlap between paragangliomas and schwannomas. ...
Abstract
Background and Purpose:
Differentiating paragangliomas from schwannomas and
distinguishing sporadic from neurofibromatosis type 2 (NF 2)-related schwannomas is
challenging but clinically important. This study aimed to assess the utility of dynamic
susceptibility contrast perfusion MRI (DSC-MRI) and diffusion-weighted imaging (DWI) in
discriminating infratentorial extra-axial schwannomas from paragangliomas and NF2-
related schwannomas.
Methods:
This retrospective study included 41 patients diagnosed with paragangliomas,
sporadic schwannomas, and NF2-related schwannomas in the infratentorial extra-axial
space between April 2013 and August 2021. All cases had pretreatment DSC-MRI and
DWI. Normalized mean apparent diffusion coefficient (nADCmean), normalized relative
cerebral blood volume (nrCBV), and normalized relative cerebral blood flow (nrCBF) were
compared between paragangliomas and schwannomas and between sporadic and NF2-
related schwannomas as appropriate.
Results:
nrCBV and nrCBF were significantly higher in paragangliomas than in sporadic/
NF2-related schwannomas (nrCBV: median 11.5 vs. 1.14/3.74; p < .001 and .004, nrCBF:
median 7.43 vs. 1.13/2.85; p < .001 and .007, respectively), while nADCmean were not.
The corresponding diagnostic performances were area under the curves (AUCs) of .99/.92
and 1.0/.90 with cutoffs of 2.56/4.22 and 1.94/3.36, respectively. nADCmeanwere lower,
and nrCBV and nrCBF were higher in NF2-related than in sporadic schwannomas (nADCmean:
median 1.23 vs. 1.58, nrCBV: median 3.74 vs. 1.14, nrCBF: median 2.85 vs. 1.13;
all p < .001), and the corresponding diagnostic performances were AUCs of .93, .91, and
.95 with cutoffs of 1.37, 2.63, and 2.48, respectively.
Conclusions:
DSC-MRI and DWI both can aid in differentiating paragangliomas from schwannomas and sporadic from NF2-related schwannomas.
... Larger tumors are often more complex and can be lobulated or multinodular in appearance [14]. In general PGL are highly vascular tumors: intra-tumoral and peri-tumoral vessels may be evident, and necrosis is common in larger lesions [15]. ...
... Similar to head and neck PGLs, a classical 'salt and pepper' appearance of PGLs can be seen on T1w and T2w imaging, particularly in larger tumors [11] (Fig. 8). This appearance reflects a combination of intratumoral vascularity (low signal flow voids) and hyperintense foci due to microhemorrhages on T1w or slow-flowing blood on T2w [15]. Restricted diffusion is almost always present, even in small tumors [11,13] (Fig. 7). ...
... The premise is that an appropriate peptide for the target tumor is attached to a radioisotope chosen to decay with beta emission in a timely half-life. Iodine-131 ( 131 I) can be combined with mIBG for tumors expressing norepinephrine receptors, and Yttrium-90 ( 90 Y) or Lutetium-177 ( 177 Lu) can be combined with DOTATATE for tumors expressing the somatostatin receptor [15]. This essentially delivers targeted high-dose radiation to the tumor and metastatic sites. ...
Bladder paragangliomas (bPGL) are rare neuroendocrine tumors arising from the sympathetic paraganglia present in the bladder wall. Bladder PGLs are typically submucosal or intramural but when subserosal may not be readily visible at cystoscopy. The average size at presentation is 3.9 cm (range 1.0–9.1 cm). When small, bPGL are usually spherical, well-marginated and homogeneous. Larger bPGL are typically more complex with peri- and intra-tumoral neovascularity and central necrosis. On ultrasound, increased color Doppler signal is typical. The increased soft tissue resolution of MRI enables localization of bPGL within the bladder wall more accurately than CT. Restricted diffusion and avid contrast enhancement help differentiate small bPGLs from leiomyomas, which have similar appearances on ultrasound and CT. Nuclear medicine techniques identify bPGLs and their metastases with high specificity, ⁶⁸Ga-DOTATATE PET/CT having largely replaced ¹²³I-mIBG SPECT/CT as the first line functional investigation. Imaging is essential to aid surgical planning, as endoscopic resection is often not possible or incomplete due to tumor location. For patients with advanced disease, ⁶⁸Ga-DOTATATE PET/CT and ¹²³I-mIBG SPECT/CT assess suitability for peptide receptor radionuclide therapy. Up to 63% of bPGL patients have a germline mutation, most commonly in the SDHB subunit gene, increasing their risk of developing pheochromocytomas and further paragangliomas; lifelong annual biochemical and periodic imaging screening from skull base to pelvis is therefore recommended.
Graphical abstract
... Pheochromocytoma and sympathetic paragangliomas are rare neuroendocrine tumors arising from the adrenal medulla and sympathetic chains, respectively (1). These tumors can occur sporadically or as part of hereditary syndromes and are frequently linked to mutations in the succinate dehydrogenase (SDH) enzyme subunit genes (1). ...
... CT angiography presents the vascular relationships with a profuse and homogeneous tumor blush in the capillary phase or a major nutrient vessel [20], and MRI portrays the classic "salt and pepper" appearance. Anatomic and functional imaging are keys to the diagnosis of clinically suspected PGs and the development of individualized treatment strategy [21]. ...
... Hu et al. BMC Surg (2021)21:Operative imaging and pathological analysis of the new reported case. A intra-operative view of the tumor (labeled with asterisk) and the cricoid cartilage (labeled with arrow). ...
Background
Subglottic paragangliomas (PGs) are exceptionally rare and unpredictable, occasionally presenting at an atypical location. There are three different clinical forms of subglottic PGs: intraluminal (tracheal PGs), extraluminal (thyroid PGs) and the mixed type (both intraluminal and extraluminal, mixed-subglottic PGs). These tumors are usually misdiagnosed as other relatively common primary thyroid or laryngotracheal tumors, and the treatment is troublesome.
Case presentation
A 22-year-old male patient with subglottic PGs has been successively misdiagnosed as thyroid tumors and subglottic hemangiomas, and lastly underwent local extended lumpectomy and laryngotracheal reconstruction with a pedicled thoracoacromial artery perforator flap (PTAPF). The patient was decannulated successfully after the second-stage tracheal reconstruction with a local flap, and no evidence of local recurrence and distant metastasis of the tumor until now.
Conclusion
Subglottic PGs can be easily misdiagnosed as laryngotracheal or thyroid tumors when presented at an atypical location. It is essential for otolaryngologists and head and neck surgeons to remain vigilant against these tumors. If the tumor is not diagnosed or removed completely, patients may encounter a risk of lethal paroxysm, which is incredibly troublesome.
... Regarding tumor characteristics, as previous studies have reported, the presence of flow voids and the enhancement pattern showed significant differences between schwannomas and paragangliomas, while age was younger in SDH mutation-positive than SDH mutationnegative paragangliomas. 1,3,4 Semiquantitative parameters are based on and calculated from TICs, which can differentiate divergent hemodynamic patterns. In our study, TME, SER, peak enhancement, and wash-in showed significant differences between the 2 tumors. ...
Background and purpose:
Distinguishing schwannomas from paragangliomas in the head and neck and determining succinate dehydrogenase (SDH) mutation status in paragangliomas are clinically important. We aimed to assess the clinical usefulness of DWI and dynamic contrast-enhanced MR imaging in differentiating these 2 types of tumors, as well as the SDH mutation status of paragangliomas.
Materials and methods:
This retrospective study from June 2016 to June 2020 included 42 patients with 15 schwannomas and 27 paragangliomas (10 SDH mutation-positive and 17 SDH mutation-negative). ADC values, dynamic contrast-enhanced MRI parameters, and tumor imaging characteristics were compared between the 2 tumors and between the mutation statuses of paragangliomas as appropriate. Multivariate stepwise logistic regression analysis was performed to identify significant differences in these parameters.
Results:
Fractional plasma volume (P ≤ .001), rate transfer constant (P = .038), time-to-maximum enhancement (P < .001), maximum signal-enhancement ratio (P < .001) and maximum concentration of contrast agent (P < .001), velocity of enhancement (P = .002), and tumor characteristics including the presence of flow voids (P = .001) and enhancement patterns (P = .027) showed significant differences between schwannomas and paragangliomas, though there was no significant difference in ADC values. In the multivariate logistic regression analysis, fractional plasma volume was identified as the most significant value for differentiation of the 2 tumor types (P = .014). ADC values were significantly higher in nonhereditary than in hereditary paragangliomas, while there was no difference in dynamic contrast-enhanced MR imaging parameters.
Conclusions:
Dynamic contrast-enhanced MR imaging parameters show promise in differentiating head and neck schwannomas and paragangliomas, while DWI can be useful in detecting SDH mutation status in paragangliomas.
