Computed tomography angiography features of a retroperitoneal extra-adrenal paraganglioma in a cat.

A 7-year-old spayed female domestic shorthair cat was presented for evaluation of a large-volume abdominal space-occupying lesion. A computed tomography angiography examination detected a round retroperitoneal mass, in contact with the large abdominal vessels, characterized by an external hyperattenuating capsule and a larger hypoattenuating center. The capsule was soft-tissue attenuating with marked heterogenous contrast enhancement. The center was hypoattenuating pre- and post-contrast administration. The mass displaced both kidneys laterally and the descendent colon ventrally. The mesenteric veins and both phrenicoabdominal veins were markedly increased in diameter. However, the adrenals were not involved. On the excretory phase, no contrast enhancement was observed in either ureter, except for the proximal tract of the right ureter. At laparotomy, both ureters entered the mass that was adherent to the great abdominal vessels. The cytological diagnosis was retroperitoneal extra-adrenal paraganglioma. In cats, retroperitoneal extra-adrenal paragangliomas are very rare. This is the first computed tomography angiography report of a retroperitoneal extra-adrenal paraganglioma in a domestic cat. Key clinical message: This report describes the computed tomography angiography features of a rare case of a retroperitoneal extra-adrenal paraganglioma in a cat. These features could be taken into consideration to direct the diagnosis of a possible neuroendocrine origin for a retroperitoneal mass in a cat.

Caractéristiques de l'angiographie par tomodensitométrie d'un para-gangliome extra-surrénalien rétropéritonéal chez un chatUne chatte domestique à poils courts, âgée de 7 ans, stérilisée, a été présentée pour évaluation d'une lésion abdominale de grand volume occupant de l'espace. Un examen d'angiographie tomodensitométrique a détecté une masse rétropéritonéale ronde, en contact avec les gros vaisseaux abdominaux, caractérisée par une capsule externe hyper-atténuante et un centre hypo-atténuant plus large. La capsule présentait une atténuation des tissus mous avec une prise de contraste hétérogène marquée. Le centre était hypoatténuant avant et après l'administration le milieu de contraste. La masse a déplacé latéralement les deux reins et ventralement le côlon descendant. Le diamètre des veines mésentériques et des deux veines phrénico-abdominales était nettement augmenté. Cependant, les surrénales n'étaient pas impliquées. À la phase excrétrice, aucune augmentation de contraste n'a été observée dans les deux uretères, à l'exception du tractus proximal de l'uretère droit. Lors de la laparotomie, les deux uretères pénétraient dans la masse adhérente aux gros vaisseaux abdominaux. Le diagnostic cytologique était un paragangliome extra-surrénalien rétropéritonéal. Chez le chat, les para-gangliomes extra-surrénaliens rétropéritonéaux sont très rares. Il s'agit du premier rapport d'angiographie par tomodensitométrie d'un para-gangliome extra-surrénalien rétropéritonéal chez un chat domestique.Message clinique clé:Ce rapport décrit les caractéristiques de l'angiographie par tomodensitométrie d'un cas rare de paragangliome extra-surrénalien rétropéritonéal chez un chat. Ces caractéristiques pourraient être prises en considération pour orienter le diagnostic d'une éventuelle origine neuroendocrinienne d'une masse rétropéritonéale chez un chat.(Traduit par Dr Serge Messier).

A young patient with heart failure was diagnosed with extra-adrenal paraganglioma: a case report.

BACKGROUND: We present a case of pelvic paraganglioma that presented with heart failure as the primary symptom. CASE PRESENTATION: A 35-year-old man was admitted to hospital due to heart failure. Contrast-enhanced pelvic CT showed mass shadows in the posterior wall of the bladder and multiple enlarged lymph nodes in the retroperitoneal area. Ultrasound-guided puncture was performed, and the pathologic diagnosis was extra-adrenal paraganglioma. The patient refused any chemotherapy and died within six months of diagnosis. CONCLUSION: The possibility of neuroendocrine-related tumors, for example paragangliomas, should be considered in young patients with heart failure, especially those with concomitant hypertension and diabetes.

Imaging features of retroperitoneal extra-adrenal paragangliomas in 10 dogs.

Retroperitoneal paragangliomas are rare tumors of the neuroendocrine system. Only a few canine case reports are available with rare descriptions of their imaging features. The objectives of this multi-center, retrospective case series study were to describe the diagnostic imaging features of confirmed retroperitoneal paragangliomas and specify their location. Medical records and imaging studies of 10 affected dogs with cytological or histopathologic results concordant with retroperitoneal paragangliomas were evaluated. Dogs had a median age of 9 years. Four of them had clinical signs and laboratory reports compatible with excessive production of catecholamines. Six ultrasound, four CT, four radiographic, and one MRI studies were included. The paragangliomas did not have a specific location along the aorta. They were of various sizes (median 33 mm, range: 9-85 mm of length). Masses had heterogeneous parenchyma in six of 10 dogs, regardless of the imaging modality. Strong contrast enhancement was found in all CT studies. Encircling of at least one vessel was detected in six of 10 masses, clear invasion of a vessel was identified in one of 10 masses. In five of 10 cases, the masses were initially misconstrued as lymph nodes by the on-site radiologist. Retroperitoneal paragangliomas appear along the abdominal aorta, often presenting heterogeneous parenchyma, possibly affecting the local vasculature, and displaying strong contrast enhancement on CT. Clinical signs can be secondary to mass effects or excessive catecholamine production. Underdiagnosis and misdiagnosis of this tumor are suspected as they can be silent, of small size, or confused with other structures.

Surgical Treatment of Primary Cardiac Paragangliomas: A Single-Center Experience.

BACKGROUND: Cardiac paragangliomas are rare neuroendocrine tumors that will cause significant morbidity if left undiagnosed. Because of the paucity of cohort data, their rapid diagnosis and appropriate management still pose unique challenges to cardiac surgeons. We aimed to investigate the clinical features and surgical management of primary cardiac paragangliomas in our single center. METHODS: From May 2014 to October 2020, patients diagnosed with primary cardiac paragangliomas retrospectively were reviewed. Demographic data, clinical presentation, preoperative imaging methods, surgical resection, perioperative management, histological analysis, and outcomes were recorded. Postoperative follow up also was reviewed. RESULTS: With multiple imaging methods, including echocardiography, computed tomography, positron-emission tomographic-computed tomography, and biochemical tests, there were five cases of primary cardiac paraganglioma verified by postoperative immunohistochemical staining, two of which were hormonally active. There were no metastatic cardiac paragangliomas, according to positron-emission tomographic-computed tomography, and all patients accepted surgical treatment. Preoperative adrenoceptor blockade was given to hormonally active patients, accordingly. Complete resection of the tumor was accomplished under cardiopulmonary bypass in each case. Tumor distribution included two masses on the roof of the left atrium, two masses in the right atrioventricular groove, and one between the ascending aorta and main pulmonary artery. Immunohistochemical staining for chromogranin, neuron-specific enolase, synaptophysin, and S-100 were positive, which were typical of cardiac paraganglioma. There were no operative deaths. All the patients had an uneventful recovery except one patient who underwent low cardiac output syndrome. During follow up (mean 4.2 years, range 0.6-7.0 years), all patients were well with New York Heart Association class I or II. Only one patient developed thyroid carcinoma three years after surgery but with no paraganglioma recurrence during periodic computed tomography, and this patient recovered well after thyroidectomy. CONCLUSION: Although cardiac paragangliomas are rare and may present surgical challenges for clinicians, surgical resection remains the choice of treatment with favorable outcomes through a multidisciplinary heart team. Moreover, lifelong surveillance still is recommended to detect possible recurrence or associated nonchromaffin tumors in time.

Mesenteric Extra-adrenal Paraganglioma - An Unusual Cause of Intermittent Abdominal Pain.

Paragangliomas are non-epithelial tumors of neuroendocrine origin that arise from the paraganglia of the sympathetic and parasympathetic nervous system. These paraganglia cells are derived from the neural crest and can be found anywhere in the body where paraganglia exist. Paragangliomas are rare tumors. It is estimated that the incidence of pheochromocytoma (intra-adrenal paraganglioma) and extra-adranal paraganglioma is 0.8 per 100,000 person years. It is commonly stated that 10 percent of paragangliomas are extra-adrenal. The majority of parasymphathetic paragangliomas reside in the skull base and along the vagus and glossopharyngeal nerves, whereas the majority of sympathetic paragangliomas can be found in the abdomen. Paragangliomas found in the mesentery are exceedingly rare, with 12 reported cases identified in the literature. We present the case of a 61-year-old female who presented to our institution with a suspected superior mesenteric artery aneurysm who was ultimately found to have an extra-adrenal paraganglioma within the small bowel mesentery of the right lower quadrant of the abdomen.

Caveat for Vascular Surgeons: Lesson Learned from Acute Onset of a Rare Aortic Paraganglioma in a Young Boy.

BACKGROUND: Paragangliomas (PGs) are rare neuroendocrine tumors arising from the extra-adrenal autonomic paraganglia that are tiny organs formed by bundles of neuroendocrine cells derived from the embryonic neural crest and capable of catecholamines secretion. Diagnosis and treatment of aortic PGs could be a challenging issue when they present as an emergency setup (sudden abdominal pain and radiological images resembling a vascular emergency). CASE REPORT: We present a rare case of a 16-year-old man with a symptomatic and bleeding left para-aortic mass, treated in emergency with embolization, before a staged videolaparoscopic resection. Histology of the mass showed the presence of a large aortic PG. CONCLUSIONS: In case of active bleeding, in emergency, vascular consultants are always involved. Sometimes, circumstances are very atypical; therefore, it is essential to keep in mind rare pathologies. In such settings, multidisciplinary approach is primary to obtain a prompt diagnosis and appropriate treatment.

Multiple intraneural glomus tumors in different digital nerve fascicles.

BACKGROUND: Glomus tumors in the digital nerve are extremely rare. Multiple intraneural glomus tumors in different digital nerve fascicles have not been previously reported. CASE PRESENTATION: We report the case of a 54-year-old male with a 1-year history of progressive numbness of the middle finger with point tenderness at the level of the middle phalanx. Surgical incision revealed the presence of two glomus tumors within different fascicles of the ulnar digital nerve of the middle finger. One tumor was excised along with surrounding fascicle, the other was removed leaving the fascicle intact. Subsequently, the patient regained function of the finger and no tumors have recurred. CONCLUSIONS: Patients and physicians should be aware of the properties of intraneural glomus tumors so that early diagnosis and treatment can be sought.

[Carney triad: Report of one case]. / Tríada de Carney. Una rara asociación de tumores infrecuentes: Caso clínico.

Carney described a disorder characterized by the presence of several uncommon tumors which were pulmonary chondromas, gastric sarcomas and extra-adrenal paragangliomas. We report a 14 year-old girl in whom multiple gastric tumors were discovered during a study of an iron deficiency anemia and was subjected to a partial gastrectomy. At 25 years of age, she developed several pulmonary chondromas and at 33 years, a mediastinal tumor with features of an extra-adrenal paraganglioma was found. At 35 years of age, a total gastrectomy was performed to remove a gastrointestinal stromal tumor with excision of peritoneal and lymph node metastasis. One year later, the patient died due to liver failure secondary to liver metastases.

Management of Carotid Bifurcation Tumors: 30-Year Experience.

BACKGROUND: The carotid bifurcation can host a variety of tumors requiring complex surgical management. Treatment requires resection and, in some cases, vascular reconstruction that may compromise the cerebral circulation. The most frequent lesion at this location is the carotid body tumor (CBT). CBT are classified according to Shamblin in 3 types depending on the degree of carotid vessels encasement. Our main objective was to report our clinical experience managing carotid bifurcation tumors throughout the last 30 years. METHODS: Between 1984 and 2014, we treated 30 patients with 32 carotid bifurcation tumors. There were 21 women and 9 men (2.3:1), with a mean age of 45.5 years (18-75). The most frequent presentation was an asymptomatic neck swelling or palpable mass localized at the carotid triangle (86.7%). RESULTS: Thirty of 32 tumors were resected. Since 1994, computed tomography scan has been the most frequently used diagnostic imaging tool (80%), followed by magnetic resonance imaging. Angiography was used mainly during the first 10 years of the study period. Mean size of the tumor was 44.6 mm (20-73 mm). Nineteen (63%) were classified as Shamblin II and 6 (20%) as Shamblin's III. All specimens were analyzed by a pathologist; 28 tumors (93%) were confirmed as paragangliomas, 2 (7%) were diagnosed as schwannomas. Two patients underwent preoperative embolization of the CBT; 5 patients (17%) required simultaneous carotid revascularization, all of them Shamblin III. Mean hospitalization time was 4.5 days (1-35 days). Transient extracranial nerve deficit was observed in 7 patients (23.3%). Three patients (Shamblin III) required red blood cells transfusion. One patient (Shamblin III) underwent a planned en bloc excision of the vagus nerve. There was no perioperative mortality or procedure-related stroke. No malignancy or tumor recurrence were observed during follow-up. CONCLUSIONS: CBTs can be diagnosed on clinical grounds requiring vascular imaging confirmation. These infrequent lesions are generally benign. Early surgical removal by surgeons with vascular expertise avoids permanent neurologic and or vascular complications.

(68)Ga-DOTATOC PET/CT provides accurate tumour extent in patients with extraadrenal paraganglioma compared to (123)I-MIBG SPECT/CT.

PURPOSE: The aim of this study was to compare the accuracy of (123)I-MIBG SPECT/CT with that of (68)Ga-DOTATOC PET/CT for staging extraadrenal paragangliomas (PGL) using both functional and anatomical images (i.e. combined cross-sectional imaging) as the reference standards. METHODS: The study included three men and seven women (age range 26 to 73 years) with anatomical and/or histologically proven disease. Three patients had either metastatic head and neck PGL (HNPGL) or multifocal extraadrenal PGL, and seven patients had nonmetastatic extraadrenal disease. Comparative evaluation included morphological imaging with CT, functional imaging with (68)Ga-DOTATOC PET, and (123)I-MIBG imaging. The imaging results were analysed on a per-patient and on a per-lesion basis. RESULTS: On a per-patient basis, the detection rate of (68)Ga-DOTATOC PET was 100 %, whereas that of planar (123)I-MIBG imaging was 10.0 % and with SPECT/CT 20.0 % for both nonmetastatic and metastatic/multifocal extraadrenal PGL. On a per-lesion basis, the overall sensitivity of (68)Ga-DOTATOC PET was 100 % (McNemar p < 0.5), that of planar (123)I-MIBG imaging was 3.4 % (McNemar p < 0.001) and that of SPECT/CT was 6.9 % (McNemar p < 0.001). Both (68)Ga-DOTATOC PET and anatomical imaging identified 27 lesions. Planar (123)I-MIBG imaging identified only one lesion, and SPECT/CT two lesions. Two additional lesions were detected by (68)Ga-DOTATOC PET but not by either (123)I-MIBG or CT imaging. CONCLUSION: Our analysis in this patient cohort indicated that (68)Ga-DOTATOC PET/CT is superior to (123)I-MIBG SPECT/CT, particularly in head and neck and bone lesions, and provides valuable information for staging extraadrenal PGL, particularly in patients with surgically inoperable tumours or multifocal/malignant disease.

18F-FDG PET/CT as a predictor of hereditary head and neck paragangliomas.

BACKGROUND: Hereditary head and neck paragangliomas (HNPGLs) account for at least 35% of all HNPGLs, most commonly due to germline mutations in SDHx susceptibility genes. Several studies about sympathetic paragangliomas have shown that (18)F-FDG PET/CT was not only able to detect and localize tumours, but also to characterize tumours ((18)F-FDG uptake being linked to SDHx mutations). However, the data concerning (18)F-FDG uptake specifically in HNPGLs have not been addressed. The aim of this study was to evaluate the relationship between (18)F-FDG uptake and the SDHx mutation status in HNPGL patients. METHODS: (18)F-FDG PET/CT from sixty HNPGL patients were evaluated. For all lesions, we measured the maximum standardized uptake values (SUVmax), and the uptake ratio defined as HNPGL-SUVmax over pulmonary artery trunk SUVmean (SUVratio). Tumour sizes were assessed on radiological studies. RESULTS: Sixty patients (53.3% with SDHx mutations) were evaluated for a total of 106 HNPGLs. HNPGLs-SUVmax and SUVratio were highly dispersed (1.2-30.5 and 1.0-17.0, respectively). The HNPGL (18)F-FDG uptake was significantly higher in SDHx versus sporadic tumours on both univariate and multivariate analysis (P = 0.002). We developed two models for calculating the probability of a germline SDHx mutation. The first one, based on a per-lesion analysis, had an accuracy of 75.5%. The second model, based on a per-patient analysis, had an accuracy of 80.0%. CONCLUSIONS: (18)F-FDG uptake in HNPGL is strongly dependent on patient genotype. Thus, the degree of (18)F-FDG uptake in these tumours can be used clinically to help identify patients in whom SDHx mutations should be suspected.

Retroperitoneal venous malformation mimics paraganglioma on triple imaging modalities.

Here, we report a case of a woman in her 50s who was referred for an incidentally discovered lesion anterior to the origin of inferior vena cava suspicious for a paraganglioma following a CT scan for vaginal bleeding. A follow-up 68Ga-DOTATATE PET-CT and MRI of the abdomen reinforced the radiological impression of an extra-adrenal paraganglioma (EAP). The EAP was deemed non-functional given normal urine biogenic amine, supine plasma fractionated metanephrines and chromogranin A levels. The mass was resected laparoscopically without perioperative blockade. Histological examination revealed a venous malformation. Extrahepatic abdominal venous malformations are rare and can be indistinguishable from an EAP on imaging preoperatively. Although benign, the lesion nevertheless warrants excision as it is associated with a risk of haemorrhage.

A retrospective comparison between 68Ga-DOTA-TOC PET/CT and 18F-DOPA PET/CT in patients with extra-adrenal paraganglioma.

PURPOSE: (18)F-Fluoro-L-dihydroxyphenylalanine ((18)F-DOPA) PET offers high sensitivity and specificity in the imaging of nonmetastatic extra-adrenal paragangliomas (PGL) but lower sensitivity in metastatic or multifocal disease. These tumours are of neuroendocrine origin and can be detected by (68)Ga-DOTA-Tyr(3)-octreotide ((68)Ga-DOTA-TOC) PET. Therefore, we compared (68)Ga-DOTA-TOC and (18)F-DOPA as radiolabels for PET/CT imaging for the diagnosis and staging of extra-adrenal PGL. Combined cross-sectional imaging was the reference standard. METHODS: A total of 5 men and 15 women (age range 22 to 73 years) with anatomical and/or histologically proven extra-adrenal PGL were included in this study. Of these patients, 5 had metastatic or multifocal lesions and 15 had single sites of disease. Comparative evaluation included morphological imaging with CT and functional imaging with (68)Ga-DOTA-TOC PET and (18)F-DOPA PET. The imaging results were analysed on a per-patient and a per-lesion basis. The maximum standardized uptake value (SUVmax) of each functional imaging modality in concordant tumour lesions was measured. RESULTS: Compared with anatomical imaging, (68)Ga-DOTA-TOC PET and (18)F-DOPA PET each had a per-patient and per-lesion detection rate of 100% in nonmetastatic extra-adrenal PGL. However, in metastatic or multifocal disease, the per-lesion detection rate of (68)Ga-DOTA-TOC was 100% and that of (18)F-DOPA PET was 56.0%. Overall, (68)Ga-DOTA-TOC PET identified 45 lesions; anatomical imaging identified 43 lesions, and (18)F-DOPA PET identified 32 lesions. The overall per-lesion detection rate of (68)Ga-DOTA-TOC PET was 100% (McNemar, P < 0.5), and that of (18)F-DOPA PET was 71.1% (McNemar, P < 0.001). The SUVmax (mean ± SD) of all 32 concordant lesions was 67.9 ± 61.5 for (68)Ga-DOTA-TOC PET and 11.8 ± 7.9 for (18)F-DOPA PET (Mann-Whitney U test, P < 0.0001). CONCLUSION: (68)Ga-DOTA-TOC PET may be superior to (18)F-DOPA PET and diagnostic CT in providing valuable information for pretherapeutic staging of extra-adrenal PGL, particularly in surgically inoperable tumours and metastatic or multifocal disease.

Isolated Cardiac Paraganglioma Encasing Right Coronary Artery With Evidence of Succinyl Dehydrogenase Gene Mutation: Successful Management Using Multimodality Imaging.

This report involves a young woman with isolated cardiac paraganglioma that was diagnosed using 68Gallium-labeled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-NaI3-octreotide positron emission tomographic scintigraphy. For the preoperative evaluation, multimodality imaging accurately described the anatomic location of the tumor and its relationship with the surrounding tissues. The patient underwent successful surgical resection of the tumor along with right coronary artery bypass grafting. The 2-month follow-up scintigraphy was normal. Next-generation sequencing evaluation revealed a novel germline mutation for the succinate dehydrogenase subunit B gene.

Mediastinal Paraganglioma: A retrospective analysis of 51 cases.

BACKGROUND: Paragangliomas are rarely found in the mediastinum, where they account for a small proportion of mediastinal masses. This study aimed to better characterize the presenting features and relevant aspects in optimizing the diagnosis and treatment of mediastinal paragangliomas. METHODS: A computer-assisted search of electronic health records was performed to identify adult patients (≥18 years) who underwent evaluation for a primary mediastinal paraganglioma at Mayo Clinic between January 2000 and April 2022. Medical charts, laboratory tests and radiology images were reviewed to collect data. RESULTS: The study included 51 patients, each with a single mediastinal paraganglioma. The median age was 47 years (IQR: 39-67), 67% females. Symptoms of catecholamine excess were manifest in 39% of patients, and 14% presented with mass effect, while the remaining 47% had no paraganglioma-related symptoms. Genetic testing was performed in 35 patients; 66% harbored a pathogenic variant in the succinate dehydrogenase enzyme complex. Most paragangliomas (71%) were in the middle mediastinum and showed uptake of intravenous contrast on chest imaging. Biopsies were performed in 30 (59%) patients; 27% were inconclusive and 10% resulted in major complications. Surgical resection occurred in 75%, primarily for relief of symptoms (50%) followed by proximity to critical structures (45%). Perioperative complications were common (66%), but there were no cases of local tumor recurrence during the follow-up period (median 8 years; IQR: 4-13). CONCLUSION: Mediastinal paragangliomas are most located in the middle mediastinum and can often be diagnosed noninvasively using a combination of clinical, biochemical, and radiological features.

Report of a vagal paraganglioma at the cervicothoracic junction.

BACKGROUND: Vagus nerve paragangliomas are rare tumors, comprising 0.03% of head and neck neoplasms. These tumors are usually located cephalad to the hyoid bone, and there is only one previously reported case that arose from the lower third of the neck. METHODS: We describe the second reported case of a lower neck vagus nerve paraganglioma that was managed with a limited sternotomy for access and surgical removal. RESULTS: A 66-year-old male presented with a long-standing lesion of the cervicothoracic junction. CT, MRI, and Ga-68 DOTATATE PET/CT showed an avidly enhancing 5.2 × 4.2 × 11.5 cm mass extending from C6 to approximately T4 level. FNA confirmed the diagnosis. The patient underwent catheter angiography and embolization via direct puncture technique followed by excision of the mass via a combined transcervical and limited sternotomy approach. CONCLUSION: We describe an unusual case of vagal paraganglioma at the cervicothoracic junction with retrosternal extension requiring a sternotomy for surgical excision.