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).

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.

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.

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.

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.

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.

Intracardiac malignant nonchromaffin paraganglioma (chemodectoma) in a cat.

A 5-year-old male castrated Domestic Shorthair cat was presented to a veterinary specialty hospital for evaluation of large-volume pleural effusion. Echocardiography revealed a large intracardiac mass at the level of the interatrial septum impairing right atrial inflow resulting in lymphocytic pleural effusion and ascites. Differential diagnoses included lymphoma, hemangiosarcoma, rhabdomyosarcoma, chemodectoma, neurofibrosarcoma, myxoma, metastatic carcinoma or intracardiac thrombus, abscess or granuloma. Due to poor long-term prognosis and recurrent, large-volume pleural effusion, the cat was humanely euthanized. The heart was submitted for histopathologic evaluation. The mass was subsequently determined to be a malignant extra-adrenal nonchromaffin paraganglioma (chemodectoma) arising from the pulmonary trunk near its bifurcation in the region of the glomus pulmonale. Chemodectomas are rare in cats and to the authors' knowledge, there are no reports of one originating from the glomus pulmonale.

False Positive of 68Ga-DOTATATE PET-CT in a Paraganglioma.

BACKGROUND: Functional imaging with 68Ga-DOTATATE PET-CT is widely employed to detect both primary and metastatic pheochromocytomas and paragangliomas (PGL), but its results may be occasionally misleading as in the case here reported. CASE PRESENTATION: We report here a 75-year-old woman with an interaortocaval PGL that was diagnosed after a hypertensive crisis occurring during the resection of a kidney tumor. 68Ga-DOTATATE PET-CT disclosed pathologic uptake in the abdomen and at the iliac crest. After the resection of the abdominal tumor, with the histological confirmation of PGL, arterial blood pressure and metanephrine levels were normalized. Genetic testing was negative. Thereafter, the bone lesion increased in size and became painful, requiring multiple medications. A selective biopsy disclosed a metastatic lesion arising from the renal tumor. CONCLUSION: The false-positive result of 68Ga-DOTATATE PET-CT is discussed.

PET/CT in a patient with cardiac paraganglioma.

A 22-year-old female with SDHB-positive who presented with palpitation and hypertension after adrenalectomy was performed 18F-FDG PET/CT to detect the primary ectopic pheochromocytoma (PCC) and rule out metastasis. PET/CT is useful for detecting and localizing the primary ectopic PCC.

Recent advances in the management of pheochromocytoma and paraganglioma.

Pheochromocytomas and paragangliomas (PPGLs) are rare tumors that cause refractory hypertension and hypertensive crisis. Although metastatic disease accounts for 30% of PPGLs, the diagnosis of malignancy is difficult without the presence of metastatic lesions. Here, we review several advancements in the diagnosis and treatment of PPGL. A nationwide epidemiological survey in Japan revealed that the annual number of patients with PPGL was 3000, which was higher than that reported previously. While plasma and urine fractionated metanephrines are recommended for use in specific biochemical testing for diagnosis, creatinine-corrected fractionated metanephrines in spot urine samples that had been widely used in Japan as a convenient screening test were shown to be as useful as 24-h urine fractionated metanephrines. Regarding imaging studies, a more specific functional imaging for PPGLs, 68Ga DOTATATE, was newly developed. 68Ga DOTATATE provides a clear image with high sensitivity and specificity. Currently, PASS or GAPP histological scores and SDHB immunostaining are clinically used to attempt to discriminate benign from malignant tumors. However, since this distinguishing process remains difficult, all cases were classified as malignant with the possibility of metastasis in the WHO classification of endocrine tumors updated in 2017. Approximately 60% of PPGLs have germline mutations in PPGL-related genes. Currently, the genes are classified into two clusters based on their mechanism for the etiology of tumorigenesis. Based on the possible mechanisms of tumor development associated with gene mutations, several molecular target drugs are under evaluation to explore more promising treatments for malignant PPGL.

Comprehensive review of evaluation and management of cardiac paragangliomas.

Cardiac paraganglioma (PGL) is a rare neuroendocrine tumour causing significant morbidity primarily due to norepinephrine secretion potentially causing severe hypertension, palpitations, lethal tachyarrhythmias, stroke and syncope. Cardiologists are faced with two clinical scenarios. The first is the elevated norepinephrine, whose actions must be properly counteracted by adrenoceptor blockade to avoid catastrophic consequences. The second is to evaluate the precise location of a cardiac PGL and its spread since compression of cardiovascular structures may result in ischaemia, angina, non-noradrenergic-induced arrhythmia, cardiac dysfunction or failure. Thus, appropriate assessment of elevated norepinephrine by its metabolite normetanephrine is a gold biochemical standard at present. Furthermore, dedicated cardiac CT, MRI and transthoracic echocardiogram are necessary for the precise anatomic information of cardiac PGL. Moreover, a cardiologist needs to be aware of advanced functional imaging using 68Ga-DOTA(0)-Tyr(3)-octreotide positron emission tomography/CT, which offers the best cardiac PGL-specific diagnostic accuracy and helps to stage and rule out metastasis, determining the next therapeutic strategies. Patients should also undergo genetic testing, especially for mutations in genes encoding succinate dehydrogenase enzyme subunits that are most commonly present as a genetic cause of these tumours. Curative surgical resection after appropriate α-adrenoceptor and ß-adrenoceptor blockade in norepinephrine-secreting tumours is the primary therapeutic strategy. Therefore, appropriate and up-to-date knowledge about early diagnosis and management of cardiac PGLs is paramount for optimal outcomes in patients where a cardiologist is an essential team member of a multidisciplinary team in its management.

Primary Lumbar Paraganglioma: Clinical, Radiologic, Surgical, and Histopathologic Characteristics from a Case Series of 13 Patients.

BACKGROUND: Paragangliomas are uncommon neuroendocrine tumors, rarely occurring in the lumbar spine. Primary lumbar paragangliomas are prominently vascularized, can present variably, and pose both diagnostic and surgical challenges. We report on a large case series with long-term follow-up and intraoperative footage to characterize the natural history, diagnostic approach, and operative approach to this rare surgical disease. METHODS: This is a single-center, retrospective cohort study including all patients with histologically confirmed primary lumbar paraganglioma treated at our tertiary neurosurgical center between 1997 and 2018. Clinical, radiologic, surgical, and histologic data were collected from medical records. RESULTS: There were 13 cases of primary lumbar paraganglioma (8 men [61.5%], 5 women [38.5%]; mean age, 51.3 years; range, 33.2-68.9 years). Symptom duration correlated with tumor size (Spearman r = 0.735, P = 0.01). The main presenting symptoms were lower back pain and radiculopathy, often long-standing with recent deterioration. Seven patients (53.8%) were admitted as emergency cases, including 3 with cauda equina syndrome. Preoperative differential diagnoses included nerve sheath tumor, ependymoma, meningioma, and disk herniation. The mean Ki-67 mitotic index was 5.7% (range, 1%-10%). Surgical resection improved pain in 8 of 13 patients (61.5%) and weakness improved in 5 of 5 patients (100%). CONCLUSIONS: Primary lumbar paragangliomas are rare neoplasms of the cauda equina that typically progress slowly but may also present acutely. They are often related to the filum terminale, which should be resected prior to other attachments intraoperatively to prevent displacement of the tumor out of view. Total resection can be curative, and long-term follow-up in this series found no recurrence.

A 46-Year-Old Woman With a Mediastinal Mass.

CASE PRESENTATION: A 46-year-old otherwise healthy woman visited the ED twice over a period of 4 days for chest discomfort, midback pain, and dyspnea. The pain was localized, constant, nonpleuritic in nature, moderate in severity, and was not relieved by over-the-counter medications.