Pheochromocytoma and Paraganglioma: Genetics, Diagnosis, and Treatment

Management of Pheochromocytomas and Paragangliomas

Pheochromocytomas and paragangliomas are distinctive neuroendocrine tumors which frequently produce excess catecholamines with resultant cardiovascular morbidity. These tumors have a strong genetic component, with up to 40% linked to hereditary pathogenic variants; therefore, germline genetic testing is recommended for all patients. Surgical resection offers the only potential cure in the case of localized disease. Given the potential for catecholaminergic crises, appropriate perioperative management is crucial, and all patients should undergo alpha-adrenergic blockade before resection. Therapeutic options for metastatic disease are limited and include surgical debulking, radiopharmaceutical therapies, and conventional chemotherapy.

Laryngeal paraganglioma: The analysis of misdiagnosed cases and literature review

Laryngeal paraganglioma (LP) is an exceptionally rare neuroendocrine tumor, underscoring importance of accurate identification to preclude misdiagnoses. In this review, we presented two typical misdiagnosed LPs, and offered reviews of LP cases reported over the preceding decade and all documented misdiagnosed LP cases. Furthermore, we systematically investigated the underlying causes of misdiagnosis and elucidated key points for effective differentiation. A retrospective analysis of 28 LP cases revealed a predominant occurrence in middle-aged women, with an average history of 25.1 months. Through an analysis of all misdiagnosed cases (n = 37), supraglottic LPs were frequently misidentified as laryngeal carcinomas and vascular tumors, while subglottic LPs were often misdiagnosed as thyroid cancers. And the occurrence of misdiagnosis resulted in delayed and inappropriate treatments, contributing to the deterioration of LP patients (14 cases, 37.8%). In conclusion, this review endeavored to heighten awareness of LPs, with the ultimate goal of advancing diagnostic precision and enhancing patient outcomes.

Head and Neck Paragangliomas: Overview of Institutional Experience

Head and neck paragangliomas (HNPGLs) are rare and have high rates of genetic mutations. We conducted a retrospective review of 187 patients with 296 PGLs diagnosed between 1974 and 2023. The mean age of diagnosis was 48.8 years (range 10 to 82) with 69.0% female and 26.5% patients with multiple PGLs. Among 119 patients undergoing genetic testing, 70 (58.8%) patients had mutations, with SDHB (30) and SDHD (26) being the most common. The rates of metastasis and recurrence were higher among patients with SDHB mutations or SDHD mutations associated with multiple PGLs. Metabolic evaluation showed elevated plasma dopamine levels were the most common derangements in HNPGL. MRI and CT were the most common anatomic imaging modalities and DOTATATE was the most common functional scan used in this cohort. Most patients (81.5%) received surgery as the primary definitive treatment, while 22.5% patients received radiation treatment, mostly as an adjuvant therapy or for surgically challenging or inoperable cases. Systemic treatment was rarely used in our cohort. Our single-center experience highlights the need for referral for genetic testing and metabolic evaluation and for a team-based approach to improve the clinical outcomes of patients with HNPGLs.

Clinical diagnosis of pheochromocytoma and paraganglioma-induced secondary hypertension through UPLC-MS/MS analysis of plasma catecholamines and their metabolites

This study aimed to elucidate the clinical diagnostic value of plasma catecholamines and their metabolites for pheochromocytoma and paraganglioma (PPGL)-induced secondary hypertension using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS). The study population included 155 patients with PPGL that were divided into the PPGL with hypertension (n = 79) and a PPGL without hypertension (n = 76) groups, and 90 healthy volunteers and 90 patients with primary hypertension as the control groups. UPLC-MS/MS was performed to detect plasma levels of catecholamines and their metabolites, including dopamine, vanillylmandelic acid (VMA), norepinephrine, metanephrine, and normetanephrine. Receiver operating characteristic curves were generated to analyze the diagnostic value of the plasma levels of catecholamines and their metabolites in PPGL-induced secondary hypertension. Patients in the primary hypertension and PPGL without hypertension groups had higher levels of dopamine, VMA, norepinephrine, metanephrine, and normetanephrine than patients in the normal group (all p < .05). On the other hand, patients in the PPGL with hypertension group had higher levels of dopamine, VMA, norepinephrine, metanephrine, and normetanephrine than patients in the normal, primary hypertension, and PPGL without hypertension groups (all p < .05). Collectively, our findings showed that dopamine, VMA, norepinephrine, metanephrine, and normetanephrine are all effective biomarkers for the diagnosis of PPGL and PPGL-induced secondary hypertension.

Paraganglioma of the Thyroid Gland: A Case Report and a Review of the Literature

Paragangliomas of the thyroid gland are rare and usually they originate from the inferior laryngeal paraganglia. In this case report, we describe the case of a 78-year-old woman who presented with an incidental finding of thyroid nodule dislocating the trachea. After a systemic and radiological evaluation, right lobo-isthmectomy was performed, and the definitive diagnosis of paraganglioma was reached. Diagnosis of these thyroidal lesions could be difficult due to their rarity, to their specific radiological aspects and the need of employing specific histological staining techniques. Once the definitive diagnosis is reached, patients should undergo a systemic and genetic evaluation. Surgery is the gold standard treatment; radiotherapy should be considered when aggressive behavior is suspected. Regular long-lasting follow-up should be proposed to these patients considering the unpredictable behavior of these lesions.

A case of neck paraganglioma in a 49-year-old male: Case report and review of the literature

INTRODUCTION AND SIGNIFICANCE

Paragangliomas are rare tumors that most commonly occur in the head and neck. They are typically slow-growing tumors that are often associated with genetic syndromes and mutations in the enzyme succinate dehydrogenase.

CASE PRESENTATION

We describe a case of a male patient who presented with ear pain and dysphagia. On physical examination, there was a left neck mass and swalling in the left oropharynx. The mass was excised through a cervical approach and it was found to be a vagal paraganglioma.

CLINICAL DISCUSSION

A few cases of head and neck paragangliomas (HNPGLs) have been reported in the medical literature. These tumors often present as asymptomatic masses, but this case, the patient presented with ear pain and dysphagia the location of the mass in the parapharyngeal space presents a surgical challenge. HNPGLs should be considered in the differential diagnosis of any neck mass.

CONCLUSION

Paragangliomas are generally considered to have a good prognosis when they are completely excised. They rarely metastasize to adjacent or distant tissues. Cervical approach is a valid option for complete excision of cervical paraganglioma.

Risk factors and a predictive nomogram for hemodynamic instability during adrenalectomy for large pheochromocytomas and paragangliomas: A retrospective cohort study

OBJECTIVE

This study aimed to investigate risk factors for intraoperative hemodynamic instability (HDI) and construct a clinical model for predicting intraoperative HDI for large pheochromocytomas and paragangliomas (PPGLs) patients.

METHODS

A single-center retrospective study of the clinicopathological data of patients undergoing surgery for PPGLs larger than 5 cm in diameter was conducted. A total of 215 eligible patients were enrolled in the study. Three advanced statistical methods were used to select independent risk factors in the training cohort for constructing a nomogram for predicting intraoperative HDI. The predictive performance of the model was assessed by area under the curve (AUC), positive predictive value (PPV), negative predictive value (NPV), and calibration. Decision curve analysis (DCA) and clinical impact curves (CIC) were used to assess predictive accuracy and clinical utility. The performance of the nomogram of was further internally validated.

RESULTS

Comorbid diabetes mellitus, anemia, hypoproteinemia, 24-h urine vanillylmandelic acid and intraoperative blood transfusion (P < 0.05) were identified as independent risk factors for constructing the nomogram. In the training cohort, the AUC, PPV and NPV of the nomogram were 0.846, 91.6% and 69.2%. In the validation cohort, the AUC, PPV and NPV were 0.842, 91.8% and 63.3%. These showed good predictive power of the model. The calibration curves demonstrated an optimal consistency between the nomogram-predicted and the actual observed survival probability. DCA and CIC examination showed superior clinical relevance.

CONCLUSIONS

The nomogram can objectively and accurately predict intraoperative HDI in patients with large PPGLs, which can help in individualized pre-treatment decision-making.

Identification of potential molecular targets for the treatment of cluster 1 human pheochromocytoma and paraganglioma via comprehensive proteomic characterization

BACKGROUND

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors. New drug targets and proteins that would assist sensitive PPGL imagining could improve therapy and quality of life of patients with PPGL, namely those with recurrent or metastatic disease. Using a combined proteomic strategy, we looked for such clinically relevant targets among integral membrane proteins (IMPs) upregulated on the surface of tumor cells and non-membrane druggable enzymes in PPGL.

METHODS

We conducted a detailed proteomic analysis of 22 well-characterized human PPGL samples and normal chromaffin tissue from adrenal medulla. A standard quantitative proteomic analysis of tumor lysate, which provides information largely on non-membrane proteins, was accompanied by specific membrane proteome-aimed methods, namely glycopeptide enrichment using lectin-affinity, glycopeptide capture by hydrazide chemistry, and enrichment of membrane-embedded hydrophobic transmembrane segments.

RESULTS

The study identified 67 cell surface integral membrane proteins strongly upregulated in PPGL compared to control chromaffin tissue. We prioritized the proteins based on their already documented direct role in cancer cell growth or progression. Increased expression of the seven most promising drug targets (CD146, CD171, ANO1, CD39, ATP8A1, ACE and SLC7A1) were confirmed using specific antibodies. Our experimental strategy also provided expression data for soluble proteins. Among the druggable non-membrane enzymes upregulated in PPGL, we identified three potential drug targets (SHMT2, ARG2 and autotaxin) and verified their upregulated expression.

CONCLUSIONS

Application of a combined proteomic strategy recently presented as "Pitchfork" enabled quantitative analysis of both, membrane and non-membrane proteome, and resulted in identification of 10 potential drug targets in human PPGL. Seven membrane proteins localized on the cell surface and three non-membrane druggable enzymes proteins were identified and verified as significantly upregulated in PPGL. All the proteins have been previously shown to be upregulated in several human cancers, and play direct role in cancer progression. Marked upregulation of these proteins along with their localization and established direct roles in tumor progression make these molecules promising candidates as drug targets or proteins for sensitive PPGL imaging.

A Comprehensive Review on Neuroendocrine Neoplasms: Presentation, Pathophysiology and Management

Neuroendocrine neoplasms (NENs) are a group of heterogeneous tumors with neuroendocrine differentiation that can arise from any organ. They account for 2% of all malignancies in the United States. A significant proportion of NEN patients experience endocrine imbalances consequent to increased amine or peptide hormone secretion, impacting their quality of life and prognosis. Over the last decade, pathologic categorization, diagnostic techniques and therapeutic choices for NENs-both well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs)-have appreciably evolved. Diagnosis of NEN mostly follows a suspicion from clinical features or incidental imaging findings. Hormonal or non-hormonal biomarkers (like serum serotonin, urine 5-HIAA, gastrin and VIP) and histology of a suspected NEN is, therefore, critical for both confirmation of the diagnosis and classification as an NET or NEC. Therapy for NENs has progressed recently based on a better molecular understanding, including the involvement of mTOR, VEGF and peptide receptor radionuclide therapy (PRRT), which add to the growing evidence supporting the possibility of treatment beyond complete resection. As the incidence of NENs is on the rise in the United States and several other countries, physicians are more likely to see these cases, and their better understanding may support earlier diagnosis and tailoring treatment to the patient. We have compiled clinically significant evidence for NENs, including relevant changes to clinical practice that have greatly updated our diagnostic and therapeutic approach for NEN patients.

Primary hepatic paraganglioma with megacolon: A case report

Primary hepatic paraganglioma (PGL) is a rare neuroendocrine tumor characterized by clinical manifestations including paroxysmal hypertension, palpitation, abdominal pain and constipation. In the present study, the case of a 21-year-old woman with pathologically confirmed hepatic PGL with megacolon following surgery is reported. The patient initially visited Beijing Tiantan Hospital (Beijing, China) for hypoferric anemia. A triple-phase CT scan of the whole abdomen showed a large hypodense mass with a solid periphery and strong arterial enhancement of the peripheral solid portion of the liver. The sigmoid colon and rectum were obviously distended, filled with gas and intestinal contents. The patient was preoperatively diagnosed with iron deficiency anemia, liver injury and megacolon and then underwent partial hepatectomy, total colectomy and enterostomy. Microscopically, the liver cells exhibited an irregular zellballen pattern. In addition, immunohistochemical staining revealed that liver cells were positive for CD56, chromogranin A, vimentin, S-100, melan-A and neuron-specific enolase. Therefore, the diagnosis of primary PGL of the liver was confirmed. These findings suggested that primary hepatic PGL should not be excluded when megacolon occurs and comprehensive imaging evaluation is of great importance for its diagnosis.

Genetic Testing for Adrenal Tumors-What the Contemporary Surgeon Should Know

Surgical diseases of the adrenal gland include pheochromocytoma/paraganglioma, primary hyperaldosteronism, Cushing syndrome, and adrenocortical carcinoma. These conditions may be associated with familial syndromes, and genetic testing is available and recommended in most. For adrenal surgeons to be familiar with these syndromes and know when to consider referral for genetic counseling and genetic testing is important. Identification of patients with familial syndromes allows for the detection and screening of associated syndromic neoplasms, guides surgical planning and operative approach, influences recurrence and malignancy risk assessment, aids in the development of a postoperative surveillance plan, and determines the need for screening family members.

Paraganglioma arising from the liver and abutting the heart

A paraganglioma is a rare extra-adrenal neuroendocrine tumour with a variable clinical presentation. A paraganglioma can arise anywhere along the sympathetic and parasympathetic chains, but it can occasionally emerge from unusual locations such as the liver and the thoracic cavity. We report a rare case of a woman in her 30s who presented to our emergency department with symptoms of chest discomfort, episodic hypertension, tachycardia and diaphoresis. A diagnostic approach including a chest X-ray, an MRI and a positron emission tomography-CT scan showed a large exophytic liver mass protruding into the thoracic cavity. For further characterisation of the mass, a biopsy of the lesion was performed, demonstrating that the tumour is of neuroendocrine origin. This was supported by a urine metanephrine test showing high levels of catecholamine breakdown products. Treatment consisted of a unique multidisciplinary approach involving hepatobiliary and cardiothoracic surgery allowing a safe and complete extermination of the hepatic tumour and its cardiac extension.

TOP2A Expression in Pheochromocytoma and Abdominal Paraganglioma: a Marker of Poor Clinical Outcome?

Pheochromocytoma and abdominal paraganglioma (PPGL) are rare neuroendocrine tumors originating from chromaffin cells. Even though only 10-15% of the tumors metastasize, all PPGLs are considered potentially malignant. Topoisomerase 2A (TOP2A) is a protein involved in cell proliferation and has been found to be over-expressed in metastatic PPGL. To provide support whether TOP2A could serve as a prognostic marker, 88 PPGLs (of which 8 metastatic/relapsing) and 10 normal adrenal gland samples were assessed for TOP2A mRNA expression using quantitative real-time PCR (qRT-PCR) and TOP2A immunohistochemistry. Comparisons to clinical parameters connected to metastatic behavior were made, and The Cancer Genome Atlas was used for validation of the results. A significant association between high TOP2A mRNA expression in primary PPGL and subsequent metastatic events (p = 0.008) was found, as well as to specific histological features and clinical parameters connected to metastatic behavior and mutations in SDHB. TOP2A immunoreactivity was calculated as an index of positive nuclei divided by the total amount of nuclei, and this index associated with TOP2A mRNA levels (p = 0.023) as well as the Ki-67 labeling index (p = 0.001). To conclude, TOP2A is a potential prognostic marker as it is frequently elevated in PPGL displaying subsequent metastatic disease, and future studies in larger cohorts are warranted to determine if a TOP2A index as assessed by immunohistochemistry could be a marker of poor outcome. Additionally, elevated levels of TOP2A could indicate a potential actionable event, and future studies with topoisomerase inhibitors would be of interest.

Case Report: A rare case of primary paraganglioma of the gallbladder with a literature review

Introduction

Paragangliomas of the gallbladder are exceptionally rare. To date, only a few cases of this disease have been reported globally, and the majority were found incidentally during surgery. Although complete resection can achieve a curative effect, specific targeted drugs may have survival benefits for patients with potential recurrence and metastasis risks.

Case presentation

A 48-year-old woman was scheduled for anatomical central hepatectomy due to the discovery of a liver mass. Surprisingly, a gallbladder tumor accompanied by intrahepatic invasion was found rather than primary liver lesions during the operation. Postoperatively, the lesion was confirmed to be a paraganglioma originating from the gallbladder with intrahepatic invasion detectable on histopathology. After surgery, the patient was treated with a new targeted drug, surufatinib {200 mg, q.d. [quaque die (every day)]}, and no recurrence was observed during the regular follow-up.

Discussion

Gallbladder paraganglioma is rare and occult, and surgeons do not know it well, so it is easily misdiagnosed before surgery. Postoperative pathological examination is the gold standard for diagnosis.

Conclusion

Given that the tumor contained abundant blood sinuses, the early and continuous enhancement of dynamic enhanced CT scanning was its characteristic manifestation. We presented a case in which a primary gallbladder paraganglioma was identified accidentally in a patient who was misdiagnosed with a liver lesion before surgery. Based on our experience in this work, the en bloc resection technique in combination with surufatinib might have a survival benefit to patients at risk of potential recurrence or metastasis; however, further follow-up observations are needed.

SDHB exon 1 deletion: A recurrent germline mutation in Colombian patients with pheochromocytomas and paragangliomas

Pheochromocytomas (PCCs) and paragangliomas (PGLs) (known as PPGL in combination) are rare neuroendocrine tumors of the adrenal medulla and extra-adrenal ganglia. About 40% of the patients with PPGL have a hereditary predisposition. Here we present a case-series of 19 unrelated Colombian patients with a clinical diagnosis of PPGL tumors that underwent germline genetic testing as part of the Hereditary Cancer Program developed at the Instituto Nacional de Cancerología, Colombia (INC-C), the largest reference cancer center in the country. Ten of 19 patients (52.63%) were identified as carriers of a pathogenic/likely pathogenic (P/LP) germline variant in a known susceptibility gene. The majority of the P/LP variants were in the SDHB gene (9/10): one corresponded to a nonsense variant c.268C>T (p.Arg90*) and eight cases were found to be carriers of a recurrent CNV consisting of a large deletion of one copy of exon 1, explaining 42% (8/19) of all the affected cases. Only one additional case was found to be a carrier of a missense mutation in the VHL gene: c.355T>C (p.Phe119Leu). Our study highlights the major role of SDHB in Colombian patients with a clinical diagnosis of PGL/PCC tumors and supports the recommendation of including the analysis of large deletions/duplications of the SDHB gene as part of the genetic counselling to improve the detection rate of hereditary cases and their clinical care.

An incidentally discovered paraganglioma that caused sinus arrest after resection

Paragangliomas are neural-crest-derived nonepithelial neuroendocrine tumors distributed along the parasympathetic and sympathetic nerves. To our knowledge, no studies were reported regarding sinus arrest on day 4 after paraganglioma resection. A 66-year-old female patient with a history of pulmonary vein isolation visited our department for sigmoid colon cancer treatment. Enhanced computed tomography revealed an enhanced small nodule-like lymph node near the root of the inferior mesenteric artery. The patient underwent laparoscopic colectomy with regional lymph node dissection. Postoperatively, paroxysmal atrial fibrillation attacks developed, and the patient resumed oral medication. Additionally, sinus arrest after tachycardia developed. Changing the oral medication could maintain her circulatory dynamics. Pathological examination revealed that differentiated tubular adenocarcinoma infiltrated the submucosa. Immunohistochemically, the excised nodule as a lymph node was considered a functional paraganglioma. Our case indicates that paraganglioma resection and oral medication resumption may contribute to sinus arrest. When arrhythmias affecting the circulation occur perioperatively, the presence of a catecholamine-producing tumor should be considered in addition to cardiac disease. J. Med. Invest. 70 : 503-507, August, 2023.

Metastatic pheochromocytoma and paraganglioma: a retrospective multicentre analysis on prognostic and predictive factors to chemotherapy

Background

Prognostic and predictive markers in metastatic pheochromocytoma and paraganglioma (mPPGL) are unknown. We aimed to evaluate epidemiology of mPPGL, and prognostic factors of overall survival (OS) and predictive markers of treatment duration with first-line chemotherapy (TD1L).

Patients and methods

Retrospective multicentre study of adult patients with mPPGL treated in Latin American centres between 1982 and 2021.

Results

Fifty-eight patients were included: 53.4% were female, median age at diagnosis of mPPGL was 36 years and 12.1% had a family history of PPGL. The primary site was adrenal, non-adrenal infradiaphragmatic and supradiaphragmatic in 37.9%, 34.5% and 27.6%, respectively. 65.5% had a functioning tumour and 62.1% had metachronous metastases. Positive uptakes were found in 32 (55.2%) ⁶⁸Gallium positron emission tomography (PET/CT), 27 (46.6%) 2-deoxy-2-[fluorine-18]fluoro-D-glucose PET/CT and 37 (63.8%) of ¹³¹Iodine-metaiodobenzylguanidine (MIBG) tests. Twenty-three (40%) patients received first-line chemotherapy, with cyclophosphamide, vincristine and dacarbazine used in 12 (52%) of patients. At a median follow-up of 62.8 months, median TD1L was 12.8 months. Either functional exams, tumour functionality, pathological characteristics or primary tumour location were significantly associated with response or survival. Yet, negative MIBG, Ki67 ≥ 10%, infradiaphragmatic location and functional tumours were associated with numerically inferior OS.

Conclusions

In patients with mPPGL, prognostic and predictive factors to chemotherapy are still unknown, but negative MIBG uptake, Ki67 ≥ 10%, infradiaphragmatic location and functional tumours were numerically linked to worse OS. Our results should be further validated in larger and independent cohorts.

Development and validation of a novel nomogram predicting pseudohypoxia type pheochromocytomas and paragangliomas

PURPOSE

Pseudohypoxia type (PHT) pheochromocytomas and paragangliomas (PPGLs) are more likely to metastasize and have a poor prognosis. However, application of genetic tests has many restrictions. The study aims to establish a novel nomogram for predicting the risk of PHT PPGLs.

METHODS

This retrospective cross-sectional study included 242 patients with pathology confirmed PPGLs in one tertiary care center in China in 2010-2021. Clinical and biochemical characteristics were collected. Next-generation sequencing was performed in all PPGLs patients for detection of mutation. Univariate and multivariable logistic regression analyses were used to select risk factors for constructing the nomogram. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the discrimination of the nomogram and the calibration curve was performed.

RESULTS

Four variables including age ≤ 35 years, hypertension, 24 h urinary output of urinary vanillylmandelic acid (VMA) ≥ 100 umol/24 h and urinary 17-ketosteroide (17 KS) ≤ 50 umol/24 h levels were independently associated with PHT PPGLs in the logistic regression analysis and were included in the nomogram. The nomogram showed a good discrimination performance with AUC of 0.829 [95% confidence interval (CI), 0.767-0.891] in the training set and 0.797 (95%CI, 0.659-0.935) in the validation set, respectively. The calibration curve showed a bias-corrected AUC of 0.809 vs. 0.795, and a Hosmer-Lemeshow (H-L) test yielded a p value of 0.801 vs. 0.885, indicating the nomogram's good ability to distinguish PHT PPGLs from non-PHT PPGLs.

CONCLUSION

Our study has proposed a novel nomogram for individualized prediction of the PHT PPGLs, which may make contributions to guide the patients' personalized management, follow-up, and treatment.

Initial characterization of immune microenvironment in pheochromocytoma and paraganglioma

Due to fewer adverse events, faster onset of action, and longer durable responses compared to chemotherapy, immunotherapy has been widely used to treat advanced solid tumors. Moreover, immunotherapy can improve the autoimmune status, thus allowing patients to benefit from the treatment in the long term. The immune microenvironment status is closely associated with the response to chemotherapies. Here, we analyzed the characteristics of the immune microenvironment in pheochromocytoma and paraganglioma (PPGL). Immunohistochemistry showed that PD-L1 is sparely expressed in PPGL with low positive rates and low expression levels, an expression pattern, that is, not correlated with tumor malignancy. Moreover, the level of intratumoral CD4⁺ and CD8⁺ lymphocyte infiltration in PPGL is low, suggesting that the immune microenvironment in PPGL may be in "immune desertification" or "immune rejection" states in which CD4⁺ and CD8⁺ lymphocyte infiltration is prevented, rendering immunotherapy less effective. In sum, our results indicate that PPGL is a microsatellite-stable tumor with low tumor mutational burden (TMB) levels, weak neoantigen production, and poor tumor antigenicity, hinting at a poor response of PPGL to chemotherapies.

Diagnostic features and therapeutic strategies for malignant paraganglioma in a patient: A case report

BACKGROUND

Paragangliomas and extra-adrenal pheochromocytomas are uncommon neuroendocrine tumors with ubiquitous distribution. Malignant paraganglioma is a relatively rare entity. We report the treatment and pathological characteristics of a patient with malignant paraganglioma, and summarize the latest advances in the treatment of malignant paraganglioma based on a literature review.

CASE SUMMARY

A 45-year-old Chinese woman presented to the hospital due to pain in the waist (right side) and right buttock, and was diagnosed as malignant paraganglioma after the placement of ureteral stent, implantation of ileus catheter, and transvaginal removal of the vaginal mass. After relief of intestinal obstruction, the patient received intravenous chemotherapy and peritoneal perfusion chemotherapy. Although her pelvic mass disease was stable, she developed multiple liver metastases and bone metastases. Due to the development of spinal cord compression, she underwent orthopedic surgery, followed by radiotherapy, and molecular targeted therapy with apatinib, but with poor disease control.

CONCLUSION

Clinical management of paraganglioma is challenging for endocrinologists and oncologists. Prospective studies are required to develop standardized therapeutic strategies for malignant paragangliomas.

Unusually large paraganglioma complicated with successive catecholamine crises: A case report and review of the literature

Background

Paragangliomas are rare neuroendocrine tumors that could secret catecholamines. Hypertension and heart failure caused by the catecholamine crisis are fatal cardiovascular events. However, silent paragangliomas that lack typical symptoms of catecholamine pose a significant diagnostic challenge.

Case summary

A 45-year-old woman who presented with more than 1-year history of abdominal discomfort was suspected of having a gastrointestinal stromal tumor by a local hospital since a vast metastatic mass occupied her left abdomen. Thus, she was recommended to our hospital. After completing the gastroscopy, she unexpectedly developed acute heart failure and was transferred to the Intensive Care Unit (ICU) where the initial diagnosis of paraganglioma was considered through path. However, a second catecholamine crisis due to constipation led to acute heart failure again. After anti-heart failure therapy and rigorous preoperative preparation, surgery was arranged to remove the tumor. Postoperative pathology confirmed the paraganglioma, and the patient was discharged from the hospital in good condition.

Conclusion

We reported a rare case of huge retro-peritoneal paraganglioma with successive catecholamine crises and acute heart failure. This was probably the largest retro-peritoneal paraganglioma since the 1980s. Besides, we were the first to use surgical drawing to illustrate its complex anatomical adjacent relationship of retro-peritoneal paraganglioma. Our case emphasizes the inclusion of extra-adrenal paraganglioma in the differential diagnosis of retroperitoneal tumors. In suspected paragangliomas, catecholamine testing is preferable to invasive procedures including gastroscopy and biopsy to avoid triggering a catecholamine crisis. Surgical resection is the primary treatment. We highlight the priority of dealing with the venous reflux branches of the tumor to prevent the release of catecholamines into the blood. In particular, preoperative preparation plays a vital role in managing paraganglioma. Moreover, it is necessary to schedule genetic testing and clinical follow-up due to the metastatic potential of paragangliomas.

Pheochromocytoma of the prostate: An unusual location

Ectopic pheochromocytomas, also called paragangliomas, are defined as catecholamine -secreting tumors, which develop outside the adrenal medulla.

Pheochromocytomas of the urinary tract represent less than 1% of all paragangliomas and are most commonly located in the bladder. Nevertheless, prostatic pheochromocytoma is an extremely rare clinical entity and only a few cases have been reported in the medical literature.

Herein, we report a case of ectopic pheochromocytoma arising from the prostate, revealing with hypertensive crisis occurring immediately after ejaculation.

Aorto-iliac paraganglioma: Case report and literature review

Introduction

Paraganglioma and pheochromocytoma are uncommon conditions that affect around 1.5–9 patients per million. The most frequent symptoms are headache, hypertension and diaphoresis; however, palpitations or tachycardia could be present. Malignancy is not frequent, and when is suspected, positron emission tomography (PET) should be performed. Surgery it's the gold standard treatment, with acceptable rates of morbidity and mortality.

Presentation of the case

A 33-year-old woman presented to private practice with long-standing symptoms consisting of asthenia, adynamia, and sensation of palpable masses in the neck. Due to her medical history and imaging findings, urine metanephrines were obtained, showing high values of adrenaline 6.69 (μg/24 h), noradrenaline 130.09 (μg/24 h), dopamine 262.59 (μg/24 h). PET was performed to identify hyperfunctioning masses in other locations, finding bilateral carotid hypermetabolic masses and a nodular lesion anterior to the aortoiliac bifurcation, probably malignant. Laparoscopic retroperitoneal tumor resection was performed by a laparoscopic and metabolic surgeon, with intraoperative findings of a vascularized mass (30 × 25 mm) closely related to the left aortoiliac bifurcation and peritoneal fluid.

Discussion

Paragangliomas are rare tumors that frequently produce catecholamines with varied symptoms. Diagnosis requires patient history, laboratory studies including 24-hour urine-metanephrines and plasma metanephrine levels. Imaging such as CT, MRI and PET scan are necessary. Perioperative management needs to be performed and surgery is the basis of the treatment in patients with localized disease. Metastatic disease has a 50% mortality at 5 years and requires a different approach.

Conclusion

Paraganglioma is a rare and complex entity that requires a multidisciplinary approach.

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Paragangliomas are rare tumors that produce catecholamines with varied symptoms.

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Diagnosis requires a detailed history, laboratory and imaging studies.

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Perioperative management needs to be performed by a multidisciplinary board.

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Surgery is the cornerstone treatment of this pathology.

PGL4 syndrome in a patient with synchronous paraganglioma-pheochromocytoma

Pheochromocytoma and paraganglioma (PGL) are rare neuroendocrine tumours, frequently associated with genetic syndromes. We report the case of a man in his 40s with a left anterior neck mass and a history of hypertensive crisis, heavy sweating and constipation. Biochemical tests showed increased plasma and urine normetanephrines. Neck ultrasound suggested left carotid body PGL, but it was mandatory to search for other lesions. Whole-body MIBG failed to show abnormal uptake. Abdominal MRI was suggestive of another PGL, anterior to the right adrenal gland. Abdominal surgery was performed uneventfully under alpha and beta blockers. This intervention proved to be effective, as normetanephrines levels became completely normal after 1 month. Carotid body PGL was successfully excised 4-months later. Genetic study identified a large deletion in exon 1 of the SDHB gene allowing the diagnosis of paraganglioma syndrome type 4 (PGL4). After 19 months of follow-up, he is still on clinical and biochemical remission and will continue life-long surveillance.

Primary Paraganglioma of the Spine: A Systematic Review of Clinical Features and Surgical Management in Cauda Equina vs Non-Cauda Equina Lesions

BACKGROUND

Primary spine paragangliomas are rare tumors. Surgical resection plays a role, but aggressive lesions are challenging. We reviewed the literature on primary spine paragangliomas.

METHODS

PubMed, Scopus, Web of Science, and Cochrane were searched upon the PRISMA guidelines to include studies on primary spine paragangliomas. Clinical-radiological features, treatments, and outcomes were analyzed and compared between cauda-equina vs non-cauda-equina tumors.

RESULTS

We included 143 studies comprising 334 patients. Median age was 46 years (range, 6-85). The most frequent symptoms were lower-back (64.1%) and radicular (53.9%) pain, and sympathetic in 18 patients (5.4%). Cauda-equina paragangliomas (84.1%) had frequently lumbar (49.1%) or lumbosacral (29%) locations. Non-cauda-equina tumors were mostly in the thoracic (11.4%), thoracolumbar (5.1%), and cervical (3.6%) spine. Median tumor diameter was 2.5cm (range, 0.5-13.0). Surgical resection (98.5%) was preferred over biopsy (1.5%). Decompressive laminectomy (53%) and spine fusion (6.9%) were also performed. Adjuvant radiotherapy was delivered in 39 patients (11.7%) with aggressive tumors. Post-treatment symptomatic improvement was described in 86.2% cases. Median follow-up was 19.5 months (range, 0.1-468.0), and 23 patients (3.9%) had tumor recurrences. No significant differences were found between cauda-equina vs non-cauda-equina tumors.

CONCLUSION

Surgical resection is effective and safe in treating primary spine paragangliomas; however, adjuvant treatments may be needed for aggressive lesions.

Glomus jugulare in a pediatric patient: case report and literature review

PURPOSE

The jugular and tympanic glomus are rare neoplasms in the general population, being even more uncommon in the pediatric population. There is considerable morbidity associated with both disease and treatment. Treatment is essentially surgical, carried out in recent years in a multidisciplinary manner using preoperative embolization associated with microsurgery and eventually adjuvant radiotherapy. The outcome depends on the location of the lesion and its proximity to noble structures in addition to multidisciplinary monitoring in the postoperative period.

METHODS

In this article, a literature review was carried out in the PubMed database, finding reports from 17 patients diagnosed with the disease. Only articles in English were considered.

RESULTS

Moreover, we reported a case of a 14-year-old patient diagnosed with jugulotympanic glomus who underwent radical surgical treatment of the lesion.

CONCLUSION

This is a rare case of jugulotympanic glomus in a pediatric patient, who underwent surgical treatment associated with multidisciplinary therapy, with a favorable postoperative outcome.

Perioperative Management of Pheochromocytomas and Sympathetic Paragangliomas

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors arising from chromaffin cells of the adrenal medulla or extra-adrenal paraganglia, respectively. PPGLs have the highest degree of heritability among endocrine tumors. Currently, ~40% of individuals with PPGLs have a genetic germline and there are at least 12 different genetic syndromes related to these tumors. Metastatic PPGLs are defined by the presence of distant metastases at sites where chromaffin cells are physiologically absent. Approximately 10% of pheochromocytomas and ~40% of sympathetic paragangliomas are linked to metastases, explaining why complete surgical resection is the first-choice treatment for all PPGL patients. The surgical approach is a high-risk procedure requiring perioperative management by a specialized multidisciplinary team in centers with broad expertise. In this review, we summarize and discuss the most relevant aspects of perioperative management in patients with pheochromocytomas and sympathetic paragangliomas.

Predictive Factors for Catecholamine-Induced Cardiomyopathy in Patients with Pheochromocytoma and Paraganglioma

OBJECTIVE

To investigate possible predictive factors of catecholamine-induced cardiomyopathy in pheochromocytoma and paraganglioma (CICMPP) patients.

METHODS

In all, 50 CICMPP patients and 152 pheochromocytoma and paraganglioma (PPGL) patients without CICMPP who were treated in our institution between August 2012 and April 2018 were included in this retrospective study to assess predictors of CICMPP.

RESULTS

Patients with CICMPP reported younger onset age, more clinical symptoms and signs, more family history of hypertension, and higher maximum systolic, diastolic, and mean BP and maximum HR. Medical evaluation also showed higher level of blood hematocrit, blood glucose, 24-h urine catecholamines, larger diameter of the tumor and more comorbidities, von Hippel-Lindau syndromes, and metastatic tumors in these patients. Multivariable analysis identified maximum resting HR over 115 beats/min (OR 10.05, 95% CI 3.71-27.20), maximum resting systolic BP over 180 mmHg (OR 7.17, 95% CI 2.22-23.23), blood glucose over 8.0 mmol/L (OR 6.52, 95% CI 2.25-18.86), more than 3 symptoms and signs (OR 6.05, 95% CI 1.86-19.64), and onset age under 40 years (OR 3.74, 95% CI 1.37-10.20) as independent predictors of CICMPP. Female sex (OR 5.06, 95% CI 1.19-21.54), complaint of chest pain (OR 5.84, 95% CI 1.27-26.90), and extra-adrenal tumor (OR 8.64, 95% CI 1.82-40.94) were independent predictors of Takotsubo cardiomyopathy in CICMPP.

CONCLUSION

Maximum resting HR ≥115 beats/min, maximum resting systolic BP ≥180 mmHg, blood glucose ≥8.0 mmol/L, number of symptoms and signs ≥3, and onset age ≤40 years were found to be predictive factors for CICMPP.

Antiproliferative effects of metformin in cellular models of pheochromocytoma

Pheochromocytomas (PCCs) are rare neuroendocrine tumors derived from adrenal medulla chromaffin cells. Malignancy and recurrence are rare but demand effective treatment. Metformin exerts antiproliferative effects in several cancer cell lines. We thus evaluated the effects of metformin on cell viability and proliferation, cellular respiration and AMPK-AKT-mTOR-HIFA proliferation pathway on a rat PCC cell line (PC12-Adh). We then addressed metformin's effects on the AMPK-AKT-mTOR-HIFA pathway on two human primary cultures: one from a VHL-mutant PCC and other from a sporadic PCC. Metformin (20 mM) inhibited PC12-Adh cell proliferation, and decreased oxygen consumption, ATP production and proton leak, in addition to loss of mitochondrial membrane potential. Further, metformin induced AMPK phosphorylation and impaired AMPK-PI3k-AKT-mTOR pathway activation. The mTOR pathway was also inhibited in human VHL-related PCC cells, however, in an AMPK-independent manner. Metformin-induced decrease of HIF1A levels was likely mediated by proteasomal degradation. Altogether our results suggest that metformin impairs PCC cellular proliferation.

Protocol for presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas: a multidisciplinary approach

OBJECTIVE

To offer a practical guide for the presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas (PGLs).

METHODS

This protocol was based on a comprehensive review of the literature and on our own multidisciplinary team's experience from managing pheochromocytoma and sympathetic PGLs at a referral center.

RESULTS

Patients with pheochromocytomas and sympathetic paragangliomas (PGLs) may develop potentially life-threatening complications, especially during surgical procedures. A complete biochemical, radiological, genetic, and cardiological assessment is recommended in the preoperative stage as it provides an evaluation of the risk of surgical complications and malignancy, allowing individualization of the presurgical treatment. Treatment with α-blockade and proper volume expansion in the preoperative stage significantly reduces the perioperative morbidity. During surgery, the anesthesiologist should look for a deep anesthetic level that inhibits the cardiovascular effects of catecholamines to minimize the risk of intraoperative complications.

CONCLUSIONS

An optimal presurgical evaluation of pheochromocytomas/ sympathetic PGL requires a multidisciplinary approach, including a complete hormonal, radiological, cardiac, genetic, and functioning evaluation in most cases. A proper preoperative evaluation in combination with strict blood pressure and heart rate control, and blood volume status optimization, will significantly reduce the risk of intraoperative and perioperative complications. In those patients who unfortunately develop intraoperative complications, the role of the anesthesiologist is essential since the selection of the appropriate management has a direct impact on morbimortality reduction.

Pediatric Neck Masses: Imaging Guidelines and Recommendations

Neck masses commonly present in children and several potential diagnostic and management pathways exist, though with a paucity of evidence-based recommendations. The purpose of this article is to evaluate the current literature and utilization of various diagnostic imaging modalities , with a review of imaging features and management pearls for pediatric neck masses. A comprehensive understanding and practical imaging workflow will guide optimal patient workup and management.

Hereditary paraganglioma presenting with atypical symptoms: Case report

RATIONALE

Paraganglioma (PGL), an extra-adrenal pheochromocytoma, is a rare tumor, especially in children. While hypersecretion of catecholamines causes the classic triad of headaches, palpitations, and profuse sweating, prompt diagnosis is still challenging.

PATIENT CONCERNS

For 7 months, an 8-year-old boy complained of polyuria and weight loss, followed by proteinuria and headache for 1 month prior to admission. He was admitted to our hospital due to an afebrile seizure.

DIAGNOSIS

His blood pressure remained markedly elevated even after cessation of the convulsion. Magnetic resonance imaging of the brain revealed posterior reversible encephalopathy syndrome. Abdominal computed tomography showed a mass lesion encasing the left renal artery, measuring 41 mm in length along its major axis. The plasma and urine levels of normetanephrine were elevated. Additionally, iodine-123-metaiodobenzylguanidine scintigraphy showed an abnormal uptake in the abdominal mass with no evidence of metastasis. Based on these findings, we tentatively diagnosed him with PGL.

INTERVENTION

Substantial alpha- and beta-blocking procedures were performed, followed by a tumor resection and an extended left nephrectomy on day 31 of hospitalization. Pathological findings confirmed the diagnosis of PGL.

OUTCOME

The postoperative course was uneventful, and his blood pressure normalized without the use of antihypertensive agents. Genetic testing revealed a known SDHB germline mutation. The same mutation was also detected on his father and paternal grandfather without any history of hypertension or malignant tumor.

LESSON

It remains challenging to diagnose pheochromocytoma/paraganglioma (PPGL) promptly because PPGL can present with a variety of symptoms. Preceding symptoms of the presented case might be caused by PGL. Although PPGL is a rare disease, especially in children, it should be considered in differential diagnosis when various unexplained symptoms persist.

Imaging of Petrous Apex Lesions

The petrous apex may be affected by a range of lesions, commonly encountered as incidental and asymptomatic findings on imaging performed for other clinical reasons. Symptoms associated with petrous apex lesions commonly relate to mass effect and/or direct involvement of closely adjacent structures. Petrous apex lesions are optimally assessed using a combination of high-resolution CT and MRI of the skull base. Management of petrous apex lesions varies widely, reflecting the range of possible pathologies, with imaging playing a key role, including lesion characterization, surveillance, surgical planning, and oncological contouring.

A simultaneous extraction/derivatization strategy coupled with liquid chromatography-tandem mass spectrometry for the determination of free catecholamines in biological fluids

The current study presents a convenient, rapid and effective simultaneous extraction/derivatization (SEDP) strategy for effective pretreatment of catecholamines (CAs). Commercial zirconium oxide (ZrO₂) nanoparticles were employed for the selective capturing of cis-diol containing CAs to remove the biological interferences and phenyl isothiocyanate (PITC) was used for derivatization to improve the ionization and to improve the chromatographic separation. The extraction and derivatization procedures were integrated into one step to simplify the sample pretreatment. Excessive derivatization reagents were removed as well, reducing the degree of contaminations in mass spectrometry. The factors affecting the SEDP process were optimized and the results showed that the detection sensitivity and chromatographic separation of CAs greatly improved compared with underivatized CAs, during LC-MS/MS analysis. Combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), quantifying the concentration of norepinephrine (NE), epinephrine (E) and dopamine (DA) in biological fluids was validated in ranges of 1-200.0 ng/mL with a satisfactory correlation coefficient (R² > 0.997). The obtained recoveries were in the range of 91.0-109.5% with RSDs less than 9.4%. Finally, significant changes in CAs levels in urine samples of healthy people and pheochromocytoma patients were detected. The developed method offers comparative advantages in terms of sensitivity, specificity and selectivity.

Insights into Mechanisms of Pheochromocytomas and Paragangliomas Driven by Known or New Genetic Drivers

Simple Summary

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors that are often hereditary. Although research has advanced considerably, significant gaps still persist in understanding risk factors, predicting metastatic potential and treating aggressive tumors. The study of rare mutations can provide new insights into how pheochromocytomas and paragangliomas develop. In this review, we provide examples of such rare events and how they can inform our understanding of the spectrum of mutations that can lead to these tumors and improve our ability to provide a genetic diagnosis.

Abstract

Pheochromocytomas and paragangliomas are rare tumors of neural crest origin. Their remarkable genetic diversity and high heritability have enabled discoveries of bona fide cancer driver genes with an impact on diagnosis and clinical management and have consistently shed light on new paradigms in cancer. In this review, we explore unique mechanisms of pheochromocytoma and paraganglioma initiation and management by drawing from recent examples involving rare mutations of hypoxia-related genes VHL, EPAS1 and SDHB, and of a poorly known susceptibility gene, TMEM127. These models expand our ability to predict variant pathogenicity, inform new functional domains, recognize environmental-gene connections, and highlight persistent therapeutic challenges for tumors with aggressive behavior.

Metastatic urinary bladder paraganglioma on Ga-68 DOTATATE PET/CT

Paragangliomas are extra-adrenal catecholamine-secreting neuroendocrine tumors that can present with adrenergic signs and symptoms. The urinary bladder is a rare location for a paraganglioma, and these tumors must be distinguished from other more common bladder neoplasms. In this case report, we discuss a 59 year-old woman who initially presented with tachycardia, palpitations, chest tightness, shortness of breath, and weight loss. Laboratory evaluation showed significantly elevated catecholamines in the plasma and urine. A CT (Computed Tomography) scan of the abdomen and pelvis revealed an enhancing mass arising from the urinary bladder and an enlarged right pelvic lymph node. A follow up Ga-68 DOTATATE PET/CT (Positron Emission Tomography and/or Computed Tomography) showed increased uptake in the primary bladder mass, right pelvic lymph node, numerous skeletal lesions, and pulmonary nodules, consistent with metastatic paraganglioma of the urinary bladder. This case report demonstrates the radiological findings of metastatic urinary bladder paraganglioma and highlights the importance of skull base to mid-thigh PET/CT using Ga-68 DOTATATE. It is crucial for the radiologist to be familiar with the characteristics of urinary bladder paragangliomas and identify these tumors on imaging to allow prompt initiation of surgical resection and/or systemic therapy.

Genetics of pheochromocytoma and paraganglioma

PURPOSE OF REVIEW

This review summarizes our current understanding of germline and somatic genetics and genomics of pheochromocytomas and paragangliomas (PCC/PGL), describes existing knowledge gaps, and discusses future research directions.

RECENT FINDINGS

Germline pathogenic variants (PVs) are found in up to 40% of those with PCC/PGL. Tumors with germline PVs are broadly categorized as Cluster 1 (pseudohypoxia), including those with SDH, VHL, FH, and EPAS1 PVs, or Cluster 2 (kinase signaling) including those with NF1, RET, TMEM127, and MAX PVs. Somatic driver mutations exist in some of the same genes (RET, VHL, NF1, EPAS1) as well as in additional genes including HRAS, CSDE1 and genes involved in cell immortalization (ATRX and TERT). Other somatic driver events include recurrent fusion genes involving MAML3.

SUMMARY

PCC/PGL have the highest association with germline PVs of all human solid tumors. Expanding our understanding of the molecular pathogenesis of PCC/PGL is essential to advancements in diagnosis and surveillance and the development of novel therapies for these unique tumors.

Paraganglioma with highly malignant potential involving the rib - Case report and review of the literature

Paragangliomas are rare neuroendocrine tumors arising from paraganglion cells in sympathetic or parasympathetic chains, which may develop in the abdomen, chest, skull base, and neck. As paragangliomas have a wide range of imaging features, the diagnosis often requires tissue sampling. We present a unique case of a paraganglioma which originally presented as a rib tumor.

A 64-year-old male with right flank pain for 2 months’ was referred for a noncontrast renal colic CT. He was found to have a 3.7 × 3.5 cm soft tissue mass invading the left posterior 9th rib and paraspinal muscle. This was fluorodeoxyglucose F 18, (¹⁸F-FDG) avid, with no other distant metabolic activity. He underwent ultrasound-guided core biopsy which revealed a diagnosis of paraganglioma. A right thoracotomy with chest wall resection of 8, 9, and 10 ribs were subsequently performed. The tumor was removed along with a small portion of adherent lung. The tumor was positive for CD56, synaptophysin and chromogranin. S-100 highlighted occasional sustentacular cells, consistent with a pathologic diagnosis of a paraganglioma. The patient remains symptom free for 6 months’ after the operation.

Our case highlights that, when paragangliomas occur within the chest wall, they may present as a rib tumor and can mimic metastasis, myeloma or other primary neoplastic etiologies originating from ribs. Both imaging and pathologic diagnosis can be challenging.

Mastermind Like Transcriptional Coactivator 3 (MAML3) Drives Neuroendocrine Tumor Progression

Metastatic disease in pheochromocytomas and paragangliomas (PCC/PGL) is not well-understood. The Cancer Genome Atlas discovered recurrent MAML3 fusion genes in a subset of tumors that lacked known germline or somatic driver mutations and were associated with aggressive disease. Here, we aimed to investigate the role of MAML3 in tumorigenesis. Human PCC/PGLs were used for IHC and genetic analysis. Three neuroendocrine tumor cell lines, SK-N-SH, QGP-1, and BON-1, were transiently transfected with MAML3 (FL) or exon 1 deleted MAML3 (dEx1; mimicking the fusion), and biologic effects of overexpression were examined in vitro. We found 7% (4/55) of human PCC/PGL have UBTF∼MAML3 fusions and all were sporadic cases with metastatic disease. Fusion-positive tumors had intense MAML3 nuclear staining and increased β-catenin by IHC and showed increased WNT4 expression. In vitro, overexpression of FL and dEx1 MAML3 increased invasion in SK-N-SH, QGP-1, and BON-1 (all P < 0.05) and increased soft-agar colony formation in QGP-1 and BON-1 (all P < 0.05). Cotransfection with FL or dEx1 MAML3 and β-catenin increased TCF/LEF promoter activation by luciferase activity and coimmunoprecipitation confirmed interaction between MAML3 and β-catenin. These data suggest MAML3 is involved in WNT signaling pathway activation. In summary, UBTF∼MAML3 fusions are present in a subset of PCC/PGL and associated with metastatic disease without other known drivers. MAML3 overexpression led to increased tumorigenicity in neuroendocrine tumor cells and the mechanism of action may involve WNT signaling pathways. IMPLICATIONS: MAML3 increases tumorigenicity and invasion in neuroendocrine tumor cells and may be a prognostic marker for aggressive disease.

Endocrine emergencies in anesthesia

PURPOSE OF REVIEW

An increasing number of patients with endocrine disorders will present to the operating rooms. In this review, we outline the common endocrine disorders that the anesthesiologist may face in the perioperative time span, review the controversies in optimal management, as well as summarize the recent literature for the management of these complex patients.

RECENT FINDINGS

Perioperative management of pheochromocytoma and paraganglioma has been facilitated by improved medical management and the adoption of minimally invasive surgical techniques. An improved understanding of the sequelae of carcinoid syndrome has resulted in safer perioperative management. Perioperative glycemic management requires a fundamental understanding of perioperative fluid resuscitation and adverse events associated with the new generation oral hyperglycemic agents to prevent avoidable complications.

SUMMARY

Endocrine disorders will commonly present in the perioperative time period and the anesthesiologist plays a critical role in achieving good operative outcomes.

Malignant pheochromocytoma with cerebral and skull metastasis: A case report and literature review

BACKGROUND

Malignant pheochromocytoma with cerebral and skull metastasis is a very rare disease. Combining our case with 16 previously reported cases identified from a PubMed search, an analysis of 17 cases of malignant cerebral pheochromocytoma was conducted. This literature review aimed to provide information on clinical manifestations, radiographic and histopathological features, and treatment strategies of this condition.

CASE SUMMARY

A 60-year-old man was admitted with a progressive headache and enlarging scalp mass lasting for 3 mo. Radiographic images revealed a left temporal biconvex-shaped epidural mass and multiple lytic lesions. The patient underwent a left temporal craniotomy for resection of the temporal tumor. Histopathological analysis led to identification of the mass as malignant pheochromocytoma. The patient’s symptoms were alleviated at the postoperative 3-mo clinical follow-up. However, metastatic pheochromocytoma lesions were found on the right 6^th rib and the 6^th to 9^th thoracic vertebrae on a 1-year clinical follow-up computed tomography scan.

CONCLUSION

Magnetic resonance spectroscopy and histopathological examination are necessary to make an accurate differential diagnosis between malignant cerebral pheochromocytoma and meningioma. Surgery is regarded as the first choice of treatment.

The North American Neuroendocrine Tumor Society Consensus Guidelines for Surveillance and Management of Metastatic and/or Unresectable Pheochromocytoma and Paraganglioma

ABSTRACT

This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management and surveillance of metastatic and unresectable pheochromocytoma and paraganglioma held on October 2 and 3, 2019. The panelists consisted of endocrinologists, medical oncologists, surgeons, radiologists/nuclear medicine physicians, nephrologists, pathologists, and radiation oncologists. The panelists performed a literature review on a series of questions regarding the medical management of metastatic and unresectable pheochromocytoma and paraganglioma as well as questions regarding surveillance after resection. The panelists voted on controversial topics, and final recommendations were sent to all panel members for final approval.

Pseudotumoral form of schistosomiasis mimicking neuroendocrine tumor: a case report and brief review of the differential diagnosis of retroperitoneal masses

Differential diagnosis of retroperitoneal masses may become complex and requires careful anamnesis, physical examination and several complementary tests. We present the clinical case of a male patient aged 45 years who was diagnosed with a 4cm paraaortic lesion compatible with neuroendocrine tumor in the abdominal computed tomography (CT) exam. The workup performed with SPECT-CT, somatostatin receptors scintigraphy, MIBG scintigraphy, 24-hour urine total and fractionated catecholamines and 24-hour urine 5-OH indoleacetic did not confirm the first diagnostic impression. Finally, the lesion was biopsied and presence of micro-organisms was revealed. Further exams confirmed schistosomiasis as the cause of the paraaortic lesion. Histological diagnosis can be helpful with regard to the differential diagnosis of retroperitoneal masses.

Adrenal Pheochromocytoma Treated With Stereotactic Body Radiation Therapy

Pheochromocytoma is a rare neuroendocrine tumor arising from chromaffin cells in the adrenal medulla. In most cases, it is benign and tends to remain localized. However since it leads to the development of cardiovascular disease, it is associated with high rates of morbidity and mortality. Treatment options include medical, surgical, or ablative measures, which often adequately control the disease. Primary pheochromocytoma is conventionally treated with external beam radiation therapy (EBRT), while stereotactic body radiation therapy (SBRT) is preferred for cases with metastasis. However, literature regarding the use of SBRT for the treatment of primary disease is scarce. This case report describes a patient with an inoperable primary adrenal gland pheochromocytoma who was treated with SBRT, resulting in adequate symptomatic control during clinical follow-up.

Perioperative management of pheocromocytoma/ paraganglioma: a comprehensive review

Pheochromocytomas are rare neuroendocrine neoplasms that require adequate preoperative evaluation in order to prevent and lessen the serious complications of catecholamine hypersecretion. Preoperative management contributes to reducing morbidity and mortality rates in patients who have not been diagnosed with this condition and undergo any surgery. However, current mortality seems to be lower, a fact attributed to preoperative management with alpha blockers.