Management of phaeochromocytoma and paraganglioma in patients with germline SDHB pathogenic variants: an international expert Consensus statement

Adult and paediatric patients with pathogenic variants in the gene encoding succinate dehydrogenase (SDH) subunit B (SDHB) often have locally aggressive, recurrent or metastatic phaeochromocytomas and paragangliomas (PPGLs). Furthermore, SDHB PPGLs have the highest rates of disease-specific morbidity and mortality compared with other hereditary PPGLs. PPGLs with SDHB pathogenic variants are often less differentiated and do not produce substantial amounts of catecholamines (in some patients, they produce only dopamine) compared with other hereditary subtypes, which enables these tumours to grow subclinically for a long time. In addition, SDHB pathogenic variants support tumour growth through high levels of the oncometabolite succinate and other mechanisms related to cancer initiation and progression. As a result, pseudohypoxia and upregulation of genes related to the hypoxia signalling pathway occur, promoting the growth, migration, invasiveness and metastasis of cancer cells. These factors, along with a high rate of metastasis, support early surgical intervention and total resection of PPGLs, regardless of the tumour size. The treatment of metastases is challenging and relies on either local or systemic therapies, or sometimes both. This Consensus statement should help guide clinicians in the diagnosis and management of patients with SDHB PPGLs.

Diagnosis and Management of Pheochromocytomas and Paragangliomas: A Guide for the Clinician

OBJECTIVE

The aim of this review was to provide a practical approach for clinicians regarding the diagnosis and management of pheochromocytomas and paragangliomas (PPGLs).

METHODS

A literature search of PubMed was carried out using key words, including pheochromocytoma, paraganglioma, treatment, diagnosis, screening, and management. The discussion of diagnosis and management of PPGL is based on the evidence available from prospective studies when available and mostly from cohort studies, cross-sectional studies, and expert consensus.

RESULTS

PPGL are neuroendocrine tumors arising from the chromaffin cells of adrenal medulla and sympathetic and parasympathetic ganglia, respectively. PPGL can be localized or metastatic, and they may secrete catecholamines, causing a variety of symptoms and potentially catastrophic and lethal complications if left untreated. The rarity of these tumors along with heterogeneous clinical presentation often poses challenges for the diagnosis and management. PPGL can be associated with several familial syndromes which are important to recognize.

CONCLUSION

The last few years have witnessed an exponential growth in the knowledge around PPGL. This review aims at providing a comprehensive discussion of current concepts for clinicians regarding clinical presentation, diagnostic tools, and management strategies for PPGL.

Metastatic Malignant Glomus Jugulare Tumor: A Rare Case Report with Clinical Manifestations and Treatment Approach

BACKGROUND Paragangliomas are neuroendocrine neoplasms derived from paraganglia of the sympathetic and parasympathetic nervous systems. Parasympathetic ganglia-derived tumors, also called non-chromaffin, are located almost exclusively in the neck and skull base and are usually non-secretory and inactive. A case of malignant glomus jugulare with a metastatic cervical lymph node is described here. CASE REPORT A 24-year-old woman was referred to an otolaryngology clinic for concern of voice change for 1 month, which was associated with right progressive hearing loss, pulsating tinnitus, and right facial weakness. A clinical examination revealed a reddish mass in the right ear behind an intact tympanic membrane with right facial weakness of House-Brackmann grade VI. A bedside flexible nasopharyngoscopy revealed an immobile right vocal fold. A computed tomography scan of the brain revealed a destructive lesion within the right jugular foramen. The patient underwent embolization followed by glomus tumor resection via infra-temporal fossa with Fisch type A approach. Pathology revealed that the tumor was an infiltrative epithelioid tumor with a spindle and nesting pattern separated by fibrovascular stroma. The submitted lateral neck lymph node revealed a metastatic tumor. CONCLUSIONS Glomus jugulare tumors are uncommon paragangliomas, and malignant behavior with metastasis is extremely rare. Metastatic tumors are often associated with facial and vagal nerves palsy. There are no histological features that distinguish malignant glomus jugulare tumors. Malignant neoplasms are characterized by the presence of metastases. Tumors of the glomus jugulare that are malignant are treated with surgery, radiotherapy, or both. However, our search of the literature revealed no clear guidelines, given the scarcity of cases. Moreover, the presence of metastasis increases the risk of death.

An Update on Temporal Bone Paragangliomas

OPINION STATEMENT

Temporal bone paragangliomas (TBPs) are indolent, classically benign and highly vascular neoplasms of the temporal bone. There are two types of TBPs, tympanomastoid paragangliomas (TMPs) and tympanojugular paragangliomas (TJPs). The most common symptoms are hearing loss and pulsatile tinnitus. Diagnostic workup, besides conventional physical and laboratory examinations, includes biochemical testing of catecholamine and genetic testing of SDHx gene mutations as well as radiological examination. Although surgery is traditionally the mainstay of treatment, it is challenging due to the close proximity of tumor to critical neurovascular structures and thus the high risk of complications, especially in patients with advanced lesions. Radiotherapy and active surveillance have been increasingly recommended for selected patients. Decision on treatment should be made comprehensively. Curative effect depends on various factors. Long-term follow-up with clinical, laboratory, and radiological examinations is essential for all patients.

Metastatic Pheochromocytoma and Paraganglioma: Somatostatin Receptor 2 Expression, Genetics, and Therapeutic Responses

CONTEXT

Pheochromocytomas and paragangliomas (PPGLs) with pathogenic mutations in the succinate dehydrogenase subunit B (SDHB) are associated with a high metastatic risk. Somatostatin receptor 2 (SSTR2)-dependent imaging is the most sensitive imaging modality for SDHB-related PPGLs, suggesting that SSTR2 expression is a significant cell surface therapeutic biomarker of such tumors.

OBJECTIVE

Exploration of the relationship between SSTR2 immunoreactivity and SDHB immunoreactivity, mutational status, and clinical behavior of PPGLs. Evaluation of SSTR-based therapies in metastatic PPGLs.

METHODS

Retrospective analysis of a multicenter cohort of PPGLs at 6 specialized Endocrine Tumor Centers in Germany, The Netherlands, and Switzerland. Patients with PPGLs participating in the ENSAT registry were included. Clinical data were extracted from medical records, and immunohistochemistry (IHC) for SDHB and SSTR2 was performed in patients with available tumor tissue. Immunoreactivity of SSTR2 was investigated using Volante scores. The main outcome measure was the association of SSTR2 IHC positivity with genetic and clinical-pathological features of PPGLs.

RESULTS

Of 202 patients with PPGLs, 50% were SSTR2 positive. SSTR2 positivity was significantly associated with SDHB- and SDHx-related PPGLs, with the strongest SSTR2 staining intensity in SDHB-related PPGLs (P = .01). Moreover, SSTR2 expression was significantly associated with metastatic disease independent of SDHB/SDHx mutation status (P < .001). In metastatic PPGLs, the disease control rate with first-line SSTR-based radionuclide therapy was 67% (n = 22, n = 11 SDHx), and with first-line "cold" somatostatin analogs 100% (n = 6, n = 3 SDHx).

CONCLUSION

SSTR2 expression was independently associated with SDHB/SDHx mutations and metastatic disease. We confirm a high disease control rate of somatostatin receptor-based therapies in metastatic PPGLs.

Pheochromocytoma and paraganglioma in children and adolescents

Pheochromocytoma (PPC) and paraganglioma (PGL) are the tumors that rarely occur in the pediatric population (PPGL). Both originate from chromaffin cells, pheochromocytoma is localized in the adrenal gland, whereas paragangliomas are regarded as the tumors present in other localizations, from head to the pelvis. The clinical image is characterized by the presence of the sustained hypertension, headaches, sweating, palpitations. The symptoms are caused by the catecholamine secretion or are related to tumor mass pressure on different organs. The catecholamines and their metabolites levels in urine collection or plasma are necessary for further evaluation of the diagnosis. In pediatric population the tumors occur in multiple familial syndromes such as Multiple Endocrine type 2, Neurofibromatosis type 1, Von Hippel-Lindau syndrome, Familial Paraganglioma syndrome are related to specific mutations (SDHx, RET, VHL, NF1) leading to the characteristic phenotype. The radiological and nuclear imaging are an important part of the examination. Although CT and MR are reported to have overall good sensitivity for the tumor detection, further analysis with nuclear imaging is recommended for the specified diagnosis. Right now 68GA-DOTATATE is regarded as the tracer of choice, leading to the complex evaluation of patients with different mutations and metastatic disease. The treatment of choice is the tumor excision. Also, lately new therapeutic approaches including genetically targeted therapies are under investigation for more complex treatment of tumors with underlying genetic cause or metastatic disease. Long term follow-up after treatment to avoid recurrence or to detect it in early stadium must be performed.

Case Report: A novel EPAS1 mutation in a case of paraganglioma complicated with polycythemia and atrial septal defect

Background

Paraganglioma is a rare neuroendocrine tumor and is highly associated with hereditary susceptibility genes, often occurring as part of a genetic syndrome. The genetic heterogeneity of paraganglioma poses challenges in diagnosis, counseling, and clinical management.

Case summary

We present the case of a 60-year-old woman with hypertension, atrial septal defect, and polycythemia, who experienced paroxysmal palpitations, sweating, headache, abdominal pain, nausea, and vomiting. Her blood pressure was severely unstable. Blood laboratory tests revealed elevated catecholamine levels, contrast-enhanced CT of her whole abdomen showed a round retroperitoneal mass with soft tissue density, and somatostatin receptor imaging (68Ga PET-CT) indicated a retroperitoneal mass with abnormally increased expression of somatostatin receptor. It is interesting to note that whole exome sequencing (WES) analyses on both blood and tumor samples revealed a novel EPAS1 mutation, specifically the c.2501A > G; p.Tyr834Cys variant, which has never been reported. The patient was diagnosed with paraganglioma and underwent successful Da Vinci robot-assisted laparoscopic resection of the retroperitoneal tumor. During a 3-month follow-up period, her blood pressure stabilized, and her symptoms significantly improved.

Conclusion

This case reveals that the EPSA1 mutation may be the primary driver of paraganglioma complicated by atrial septal defect and polycythemia. Additionally, the utilization of Da Vinci robot-assisted laparoscopic surgery contributed to a favorable prognosis for the patient.

Clinical consensus guideline on the management of phaeochromocytoma and paraganglioma in patients harbouring germline SDHD pathogenic variants

Patients with germline SDHD pathogenic variants (encoding succinate dehydrogenase subunit D; ie, paraganglioma 1 syndrome) are predominantly affected by head and neck paragangliomas, which, in almost 20% of patients, might coexist with paragangliomas arising from other locations (eg, adrenal medulla, para-aortic, cardiac or thoracic, and pelvic). Given the higher risk of tumour multifocality and bilaterality for phaeochromocytomas and paragangliomas (PPGLs) because of SDHD pathogenic variants than for their sporadic and other genotypic counterparts, the management of patients with SDHD PPGLs is clinically complex in terms of imaging, treatment, and management options. Furthermore, locally aggressive disease can be discovered at a young age or late in the disease course, which presents challenges in balancing surgical intervention with various medical and radiotherapeutic approaches. The axiom-first, do no harm-should always be considered and an initial period of observation (ie, watchful waiting) is often appropriate to characterise tumour behaviour in patients with these pathogenic variants. These patients should be referred to specialised high-volume medical centres. This consensus guideline aims to help physicians with the clinical decision-making process when caring for patients with SDHD PPGLs.

The diagnosis and management of pheochromocytoma and paraganglioma during pregnancy

Diagnosis of pheochromocytoma or paraganglioma (PPGL) in pregnancy has been associated historically with high rates of materno-fetal morbidity and mortality. Recent evidence suggests outcomes are improved by recognition of PPGL before or during pregnancy and appropriate medical management with alpha-blockade. Whether antepartum surgery (before the third trimester) is required remains controversial and open to case-based merits. Women with PPGL in pregnancy are more commonly delivered by Caesarean section, although vaginal delivery appears to be safe in selected cases. At least some PPGLs express the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) which may explain their dramatic manifestation in pregnancy. PPGLs in pregnancy are often associated with heritable syndromes, and genetic counselling and testing should be offered routinely in this setting. Since optimal outcomes are only achieved by early recognition of PPGL in (or ideally before) pregnancy, it is incumbent for clinicians to be aware of this diagnosis in a pregnant woman with hypertension occurring before 20 weeks' gestation, and acute and/or refractory hypertension particularly if paroxysmal and accompanied by sweating, palpitations and/or headaches. All women with a past history of PPGL and/or heritable PPGL syndrome should be carefully assessed for the presence of residual or recurrent disease before considering pregnancy.

Paraganglioma of the Head and Neck: A Review

OBJECTIVE

To review the epidemiology, presentation, diagnosis, and management of head and neck paragangliomas.

METHODS

A literature review of english language papers with focus on most current literature.

RESULTS

Paragangliomas (PGLs) are a group of neuroendocrine tumors that arise in the parasympathetic or sympathetic ganglia. Head and neck PGLs (HNPGLs) comprise 65% to 70% of all PGLs and account for 0.6% of all head and neck cancers. The majority of HNPGLs are benign, and 6% to 19% of all HNPGLs develop metastasis outside the tumor site and significantly compromise survival. PGLs can have a familial etiology with germline sequence variations in different susceptibility genes, with the gene encoding succinate dehydrogenase being the most common sequence variation, or they can arise from somatic sequence variations or fusion genes. Workup includes biochemical testing to rule out secretory components, although it is rare in HNPGLs. In addition, imaging modalities, such as computed tomography and magnetic resonance imaging, help in monitoring in surgical planning. Functional imaging with DOTATATE-positron emission tomography, 18F-fluorodeoxyglucose, or 18F-fluorohydroxyphenylalanine may be necessary to rule out sites of metastases. The management of HNPGLs is complex depending on pathology, location, and aggressiveness of the tumor. Treatment ranges from observation to resection to systemic treatment. Similarly, the prognosis ranges from a normal life expectancy to a 5-year survival of 11.8% in patients with distant metastasis.

CONCLUSION

Our review is a comprehensive summary of the incidence, mortality, pathogenesis, presentation, workup and management of HNPGLs.

Supportive management of patients with pheochromocytoma/paraganglioma undergoing noninvasive treatment

PURPOSE OF REVIEW

Many publications review perioperative management of pheochromocytomas/paragangliomas (PPGLs); however, a large population, including 10-20% of metastatic PPGL patients, have inoperable disease. This has necessitated the development of noninvasive treatments (e.g., radio/chemotherapy), which, in affording disease-modification, have led to an ever-growing population of surviving patients with inoperable PPGL. These patients experience debilitating symptoms arising from discomforts related to the masses themselves (e.g., pain from osseous metastasis) and symptoms from tumoral catecholamine production and release. Unfortunately, management of these conditions is not yet well-defined. Adding further insult-to-injury, these noninvasive treatments can trigger catecholamine release, worsening catecholamine-induced symptoms. Herein, we detail these ailments and their management, especially while patients receive these noninvasive treatments.

RECENT FINDINGS

Improved diagnostic evaluations have allowed for earlier detection of PPGL, prolonging survival in patients with inoperable PPGLs. Accordingly, noninvasive treatment strategies have rapidly evolved alongside state-of- the-art theranostics and genetic testing, which inform ongoing management and therapeutic response.

SUMMARY

While treatments afford improved survival, there must be a corresponding attention to quality-of-life. This is ensured by employing supportive management, which mitigates debilitating symptoms. This is best accomplished with a multidisciplinary approach and familiarity with genetic and biochemical determinants which guide patient education and management.

Paragangliomas da Cabeça e Pescoço: A Experiência de um Centro Oncológico do Sul da Europa

INTRODUCTION

Paragangliomas are usually benign slow-growing tumors, but they are locally invasive and can cause significant morbidity. The aim of this study was to characterize the presenting symptoms, secretory status, genetics, imaging features, treatment modalities, post-treatment complications and survival of patients with head and neck paragangliomas treated at a single institution.

MATERIAL AND METHODS

We retrospectively reviewed the clinical records of patients managed at our center between 1997 and 2020.

RESULTS

Seventy-three patients were included in the study, encompassing 89 head and neck paragangliomas. Forty-eight patients (65.8%) were female and 15 (20.5%) had multiple tumor sites (including 10 patients with multicentric benign paragangliomas and five with disseminated malignant disease). Regarding location, our series encompassed 40 temporal bone paragangliomas (44.9%), 24 carotid body paragangliomas (27%), 22 vagal paragangliomas (24.7%), two laryngeal paragangliomas (2.2%) and one sinonasal paraganglioma (1.1%). Excessive catecholamine secretion was detected in 11 patients (15.1%). Sixty-four patients (87.7%) underwent genetic testing. Of those, 24 (37.5%) exhibited pathogenic succinate dehydrogenase complex germline mutations. Regarding patients who presented with untreated disease, 45 patients (66.2%), encompassing 55 tumors, underwent surgery as primary treatment modality, 20 (29.4%; 23 tumors) were initially treated with radiotherapy and three patients (4.4%, encompassing three solitary tumors) were kept solely under watchful waiting. Five-year overall survival was 94.9% and disease-free survival was 31.9%.

CONCLUSION

Head and neck paragangliomas are rare, slow-growing but locally aggressive tumors resulting in high morbidity but low mortality rates.

Management and outcome of metastatic pheochromocytomas/paragangliomas: a monocentric experience

BACKGROUND

Pheochromocytoma (PHEO) and paraganglioma (PGL) are rare neuroendocrine tumors releasing catecholamines. Metastatic pheochromocytomas/paragangliomas (PPGLs) occur in about 5-26% of cases. To date, the management of patients affected by metastatic disease is a challenge in the absence of guidelines.

AIM

The aim of this study was to evaluate the overall survival (OS) and the progression-free survival (PFS) in metastatic PPGLs.

METHODS

Clinical data of 20 patients referred to the Careggi University Hospital (Florence, Italy) were retrospectively collected. Follow-up ranged from 1989 to 2019. Site and size of primary tumor, biochemical activity, genetic analysis and employed therapies were considered. Data were analyzed with SPSS version 27.

RESULTS

Nine PHEOs (45%) and 11 PGLs (55%) were enrolled. Median age at diagnosis was 43.5 years [30-55]. Mean follow-up was 104.6 ± 89.3 months. Catecholamines were released in 70% of cases. An inherited disease was reported in 50% of patients. OS from the initial diagnosis (OSpt) and from the metastatic appearance (OSmtx) were lower in older patients (OSpt p = 0.028; OSmtx p < 0.001), abdominal PGLs (OSpt p = 0.007; OSmtx p = 0.041), larger tumors (OSpt p = 0.008; OSmtx p = 0.025) and sporadic disease (OSpt p = 0.013; OSmtx p = 0.008).

CONCLUSION

Our data showed that older age at the initial diagnosis, sympathetic extra-adrenal localization, larger tumors and wild-type neoplasms are related to worse prognosis. Notably, the employed therapies do not seem to influence the survival of our patients. At present, effective treatments for metastatic PPGLs are missing and a multidisciplinary approach is indispensably required.

Pediatric Metastatic Pheochromocytoma and Paraganglioma: Clinical Presentation and Diagnosis, Genetics, and Therapeutic Approaches

Although pediatric pheochromocytomas and paragangliomas (PPGLs) are rare, they have important differences compared to those in adults. Unfortunately, without timely diagnosis and management, these tumors have a potentially devastating impact on pediatric patients. Pediatric PPGLs are more often extra-adrenal, multifocal/metastatic, and recurrent, likely due to these tumors being more commonly due to a genetic predisposition than in adults. This genetic risk results in disease manifestations at an earlier age giving these tumors time to advance before detection. In spite of these problematic features, advances in the molecular and biochemical characterization of PPGLs have heralded an age of increasingly personalized medicine. An understanding of the genetic basis for an individual patient's tumor provides insight into its natural history and can guide clinicians in management of this challenging disease. In pediatric PPGLs, mutations in genes related to pseudohypoxia are most commonly seen, including the von Hippel-Lindau gene (VHL) and succinate dehydrogenase subunit (SDHx) genes, with the highest risk for metastatic disease associated with variants in SDHB and SDHA. Such pathogenic variants are associated with a noradrenergic biochemical phenotype with resultant sustained catecholamine release and therefore persistent symptoms. This is in contrast to paroxysmal symptoms (e.g., episodic hypertension, palpitations, and diaphoresis/flushing) as seen in the adrenergic, or epinephrine-predominant, biochemical phenotype (due to episodic catecholamine release) that is commonly observed in adults. Additionally, PPGLs in children more often present with signs and symptoms of catecholamine excess. Therefore, children, adolescents, and young adults present differently from older adults (e.g., the prototypical presentation of palpitations, perspiration, and pounding headaches in the setting of an isolated adrenal mass). These presentations are a direct result of genetic determinants and highlight the need for pediatricians to recognize these differences in order to expedite appropriate evaluations, including genetic testing. Identification and familiarity with causative genes inform surveillance and treatment strategies to improve outcomes in pediatric patients with PPGL.

Pheochromocytoma/paraganglioma crisis: case series from a tertiary referral center for pheochromocytomas and paragangliomas

Pheochromocytoma/paraganglioma (PPGL)-induced catecholamine crisis is a rare endocrine emergency leading to life-threatening hemodynamic instability causing end-organ damage or dysfunction. As it is associated with a significant mortality rate of approximately 15%, recognizing the signs and symptoms and making the appropriate diagnosis are critical. For this purpose, we report the clinical course of the crisis in four out of a total of six patients with a PPGL crisis from a cohort of 199 PPGL patients of a single tertiary referral center for PPGL patients in the Netherlands diagnosed between 2002 and 2020. Successful treatment of a PPGL crisis demands prompt diagnosis, vigorous pharmacological therapy, and emergency tumor removal if the patient continues to deteriorate.

Metastatic Pheochromocytomas and Abdominal Paragangliomas

CONTEXT

Pheochromocytomas and paragangliomas (PPGLs) are believed to harbor malignant potential; about 10% to 15% of pheochromocytomas and up to 50% of abdominal paragangliomas will exhibit metastatic behavior.

EVIDENCE ACQUISITION

Extensive searches in the PubMed database with various combinations of the key words pheochromocytoma, paraganglioma, metastatic, malignant, diagnosis, pathology, genetic, and treatment were the basis for the present review.

DATA SYNTHESIS

To pinpoint metastatic potential in PPGLs is difficult, but nevertheless crucial for the individual patient to receive tailor-made follow-up and adjuvant treatment following primary surgery. A combination of histological workup and molecular predictive markers can possibly aid the clinicians in this aspect. Most patients with PPGLs have localized disease and may be cured by surgery. Plasma metanephrines are the main biochemical tests. Genetic testing is important, both for counseling and prognostic estimation. Apart from computed tomography and magnetic resonance imaging, molecular imaging using 68Ga-DOTATOC/DOTATATE should be performed. 123I-MIBG scintigraphy may be performed to determine whether 131I-MIBG therapy is a possible option. As first-line treatment in patients with metastatic disease, 177Lu-DOTATATE or 131I-MIBG is recommended, depending on which shows best expression. In patients with very low proliferative activity, watch-and-wait or primary treatment with long-acting somatostatin analogues may be considered. As second-line treatment, or first-line in patients with high proliferative rate, chemotherapy with temozolomide or cyclophosphamide + vincristine + dacarbazine is the therapy of choice. Other therapies, including sunitinib, cabozantinib, everolimus, and PD-1/PDL-1 inhibitors, have shown modest effect.

CONCLUSIONS

Metastatic PPGLs need individualized management and should always be discussed in specialized and interdisciplinary tumor boards. Further studies and newer treatment modalities are urgently needed.

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.

An update on adult forms of hereditary pheochromocytomas and paragangliomas

PURPOSE OF REVIEW

Pheochromocytomas and paragangliomas (PPGL) display a strong genetic determinism with 40% of inherited forms. The purpose of this review is to provide an update on current knowledge on adult forms of hereditary PPGL and their management.

RECENT FINDINGS

PPGL are genetically-driven in 70% of cases, with germline and/or somatic mutations identified in more than 20 genes. Although eight new susceptibility genes have recently emerged, mutations on SDHx genes remain the most frequent. In addition to SDHB, mutations in SLC25A11, FH and MDH2 may predispose to a metastatic disease and somatic alterations including TERT and ATRX mutations, and the differential expression on noncoding RNAs are also associated with the occurrence of metastases.The biochemical diagnosis remains the mainstay of functional PPGL and does not differ between hereditary PPGL while the choice of the best nuclear imaging approach is dictated by the tumor type and can be influenced by the presence of a germline mutation (18F-DOPA PET/CT for cluster 2 mutation and Ga-DOTATATE PET/CT for cluster 1 mutation).

SUMMARY

A systematic genetic testing and counselling is recommended for all PPGL patients and should lead to conservative surgery and an adapted follow up, in case of hereditary form.

[Literature review in the diagnosis and treatment of malignant pheochromocytomas and paragangliomas.]

OBJECTIVE

Perform a review on the diagnosis and treatment of pheochromocytomas and malignant paragangliomas. MATERIAL AND METHOD: A search was conducted in PubMed and Google Scholar of articles or clinical guides that referred to the diagnosis and treatment of these tumors. RESULTS: For the diagnosis of malignancy, a histological confirmation of a pheochromocytoma or paraganglioma should be provided, plus the presence of metastasis confirmed by images. Methanephrines are recommended over other biochemical determinations. For staging, PET-CT with 18F-FDG or 18F-DOPA is preferred because of its greater sensitivity than conventional images. The 123I-MIBG scan should be requested when radiotherapy with 131I-MIBG is planned.For treatment, control of adrenergic symptoms through the use of α-blockers is recommended. Active surveillance was an option in selected patients with slowly progressive tumors. Surgical treatment improved OS (148 months vs 36 months p=<0.01). Therapy with 131I-MIBG was indicated in patients with positive scintigraphy, reporting a global survival of 50% at 5 years with variable tumor responses. Chemotherapy was proposed in rapidly progressive disease, reporting a median overall survival of 6 years. Ablative therapies should be considered when there is a limited number of lesions, to achieve local tumor control and reduce the symptoms of excess catecholamines. External radiation therapy at high doses would be effective for patients with local symptoms due to their tumor burden. Prospective multi-institutional clinical trials are needed to determine the true benefits of molecular therapies in these patients.

CONCLUSIONS

We recommend a multidisciplinary approach in centers of high complexity to be able to offer the entire diagnostic - therapeutic arsenal available so far that they improve the survival and quality of life of these patients.

Emerging Treatments for Advanced/Metastatic Pheochromocytoma and Paraganglioma

OPINION STATEMENT

The incidence of metastatic pheochromocytoma (PHEO) and paraganglioma (PGL) may occur in as many as 35% of patients particularly with PGL and even more frequently in those with specific mutations. Biochemical, morphological, and molecular markers have been investigated for use in the distinction of benign from malignant PHEO/PGL. PHEO/PGL metastasizes via hematogenous or lymphatic routes and shows differences based on mutational status. The most common sites of involvement in patients that have an SDHB mutation are the bone (78%), lungs (45%), lymph nodes (36%), and liver (35%). In patients with sporadic PHEO/PGL, the most common sites of metastasis are the bones (64%), lungs (47%), lymph nodes (36%), and liver (32%). Metastases may be present at presentation or may occur later. Metastases to the liver and lungs are associated with a shorter survival. Overall, the estimated 5-year survival rates are between 34 and 74%. Currently, treatments for metastatic PHEO/PGL are essentially palliative. Surgery is potentially curative; however, tumor dissemination limits the chance for a curative resection. When surgical intervention is not amenable, the therapeutic options include radiolabeled MIBG (Azedra®-iobenguane 131 was recently FDA-approved for patients > 12 years and older with iobenguane scan positive) or systemic chemotherapy with cyclophosphamide, vincristine, and dacarbazine (CVD) with an overall objective response rate (ORR) of less than 40%; however, it is not clear if the administration of CVD impacts overall survival, as nearly all patients develop progressive and ultimately fatal disease. Other treatment modalities under investigation include cytoreductive techniques, novel radiopharmaceuticals, chemotherapy, radiotherapy, immunotherapy, and experimental therapies. Here we are discussing emerging treatment for advanced/metastatic PHEO/PGL.

Genetics, diagnosis, management and future directions of research of phaeochromocytoma and paraganglioma: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension

: Phaeochromocytoma and paraganglioma (PPGL) are chromaffin cell tumours that require timely diagnosis because of their potentially serious cardiovascular and sometimes life- threatening sequelae. Tremendous progress in biochemical testing, imaging, genetics and pathophysiological understanding of the tumours has far-reaching implications for physicians dealing with hypertension and more importantly affected patients. Because hypertension is a classical clinical clue for PPGL, physicians involved in hypertension care are those who are often the first to consider this diagnosis. However, there have been profound changes in how PPGLs are discovered; this is often now based on incidental findings of adrenal or other masses during imaging and increasingly during surveillance based on rapidly emerging new hereditary causes of PPGL. We therefore address the relevant genetic causes of PPGLs and outline how genetic testing can be incorporated within clinical care. In addition to conventional imaging (computed tomography, MRI), new functional imaging approaches are evaluated. The novel knowledge of genotype-phenotype relationships, linking distinct genetic causes of disease to clinical behaviour and biochemical phenotype, provides the rationale for patient-tailored strategies for diagnosis, follow-up and surveillance. Most appropriate preoperative evaluation and preparation of patients are reviewed, as is minimally invasive surgery. Finally, we discuss risk factors for developing metastatic disease and how they may facilitate personalised follow-up. Experts from the European Society of Hypertension have prepared this position document that summarizes the current knowledge in epidemiology, genetics, diagnosis, treatment and surveillance of PPGL.

Onyx embolization of skull base paragangliomas: a single-center experience

BACKGROUND

Skull base paragangliomas are highly vascular tumors that are often embolized before surgical resection; however, the safety and efficacy of preoperative embolization using an ethylene vinyl alcohol copolymer (Onyx; Medtronic, Dublin, Republic of Ireland) in these tumors is unknown. This retrospective cohort study evaluated patient outcomes after preoperative embolization of skull base paragangliomas using Onyx.

METHODS

We retrospectively analyzed data from all patients with skull base paragangliomas who underwent preoperative Onyx embolization at our institution (January 01, 2005-December 31, 2017). Patient, tumor, embolization, and outcomes data were extracted by reviewing inpatient and outpatient clinical and imaging records.

RESULTS

Seven patients were studied (5/7 [71%] female), 6 with glomus jugulares and 1 with a glomus vagale. The median age was 52 years, and the most common presenting symptom was cranial neuropathy (6/7 [86%]). The tumor vascular supply was from the ascending pharyngeal artery in all 7 cases (100%) with additional feeders including the occipital artery in 5 (71%); internal carotid artery in 3 (43%); middle meningeal, vertebral, and internal maxillary artery each in 2 (29%); and posterior auricular artery in 1 (14%). The median postembolization tumor devascularization was 80% (range, 64-95%). The only postembolization complication was a facial palsy in 1 patient.

CONCLUSION

Preoperative embolization with Onyx affords excellent devascularization for the majority of skull base paragangliomas, and it may facilitate resection of these hypervascular lesions. The advantages provided by Onyx with respect to penetration of intratumoral vessels must be weighed against the risk of cranial neuropathy.

Disease monitoring of patients with pheochromocytoma or paraganglioma by biomarkers and imaging studies

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors, a large proportion of which secrete catecholamines. PPGL are associated with a high cardiovascular morbidity and come with a risk of malignancy. The therapy of choice is surgical resection. Nevertheless, PPGL are associated with a lifelong risk of tumor persistence or recurrence. Currently, there are no clinical, biochemical, histopathological or imaging characteristics, which can predict or exclude malignant behavior or tumor recurrence. Therefore, long-term follow-up is recommended even after apparent complete surgical removal. Early detection of recurrence is essential to reduce cardiovascular morbidity and mortality due to catecholamine secretion, to prevent morbidity by mass effects of paraganglioma (PGL) or by metastatic spread of disease. Due to the rarity of these tumors, no prospective data on long-term surveillance exist. In fact, current recommendations are based on retrospective analyses, expert opinions and case studies. The aim of this review is to provide an overview on the current state of knowledge with regard to known factors that increase the risk of recurrence and might impact disease monitoring as well as the available possibilities for biochemical and imaging follow-up. Based on this overview, we aim to propose a practical approach for a patient-oriented follow-up after surgical removal of a PPGL.

Metastatic pheochromocytoma and paraganglioma: Management of endocrine manifestations, surgery and ablative procedures, and systemic therapies

Metastatic pheochromocytomas and paragangliomas (MPPGs) are rare neuroendocrine tumors. Most patients present with advanced disease that is associated with manifestations of catecholamine release. Surgical resection of the primary tumor and ablative therapies of metastases-whenever possible-may improve clinical outcomes and, perhaps, lengthen the patient's overall survival. Significant steps in understanding the genetic alterations linked to MPPGs and scientific progress made on cancers that share a similar pathogenesis are leading to the recognition of potential systemic therapeutic options. Data derived from clinical trials evaluating targeted therapies such as tyrosine kinase inhibitors, radiopharmaceuticals, immunotherapy, and combinations of these will likely improve the outcomes of patients with advanced and progressive MPPGs. Exemplary of this success is the recent approval in the United States of the high-specific-activity iodine¹³¹ meta-iodine-benzylguanidine (MIBG) for patients with unresectable and progressive MPPGs that express the noradrenaline transporter. This review will discuss the therapeutic approaches for patients with MPPGs.

Clinical Presentation and Treatment Outcomes of Children and Adolescents With Pheochromocytoma and Paraganglioma in a Single Center in Korea

PURPOSE

Pheochromocytoma (PCC) and paraganglioma (PGL) (PPGL) are rare neuroendocrine tumors, and data on managing these conditions in children and adolescents are lacking. The objective of this study was to demonstrate the clinical presentation and treatment outcomes in children and adolescents with PPGL in a single tertiary care center in Korea.

METHODS

This retrospective study included 23 patients diagnosed with PCC (n = 14) and PGL (n = 9) before the age of 21 at Samsung Medical Center (from June 1994 to June 2019). We describe age, gender, family history, clinical characteristics, laboratory findings, pathologic findings, therapeutic approaches, and treatment outcomes.

RESULTS

Of the 23 patients, 14 had PCC and nine had PGL. The median age at diagnosis was 16.8 years (range, 6.8-20.8 years). The common presenting symptoms were hypertension (n = 10), headache (n = 9), palpitation (n = 4), and sweating (n = 4). The plasma or 24-hour urine catecholamine and/or metabolite concentrations were markedly elevated in 22 patients with PPGL, but were normal in one patient with carotid body PGL. All tumors were visualized on computed tomography. Genetic tests were performed in 15 patients, and seven patients showed mutations in RET (n = 3), SDHB (n = 3), and VHL (n = 1). All patients underwent surgery, and complete excision was performed successfully. Three patients with metastasis underwent postoperative adjuvant therapy.

CONCLUSION

This study suggests that pediatric PPGL tends to be extra-adrenal and bilateral and shows a higher potential for genetic mutations. Considering the hereditary predisposition of pediatric PPGL, genetic screening tests are strongly recommended, and lifelong follow-up is needed to detect recurrence and metastasis. Further research with a larger sample size and routine genetic screening is needed to better understand the genetic conditions and long-term prognosis of PPGL.

'Peptide receptor radionuclide therapy in the management of advanced pheochromocytoma and paraganglioma: A systematic review and meta-analysis'

OBJECTIVE

Inoperable and metastatic pheochromocytomas and paragangliomas (PPGLs) present a therapeutic challenge with current treatment options being limited to radiolabelled meta-iodo-benzyl-guanidine (MIBG) and systemic chemotherapy. Peptide receptor radionuclide therapy (PRRT) seems to be a promising option for these patients with few studies reporting favourable response. This systematic review was conducted to evaluate the efficacy and safety of PRRT in patients with advanced PPGLs.

METHODS

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Searches in PubMed, Scopus and Embase were made using relevant keywords and articles up to May 2019 were included. Data on efficacy and toxicity were extracted from the individual articles, and pooled estimates were generated using meta-analysis.

RESULTS

Twelve articles consisting of 201 patients with advanced PPGLs were included. Overall, treatment with PRRT achieved an objective response rate of 25% (95% CI: 19%-32%) and a disease control rate of 84% (95% CI: 77%-89%). Clinical and biochemical responses were seen in 61% and 64% of the patients, respectively. Among the PRRTs, similar tumour response rates were noted for ⁹⁰ Y-yttrium- and ¹⁷⁷ Lu-lutetium-based agents. Treatment-related adverse effects were minimal with grade 3/4 neutropenia, thrombocytopenia, lymphopenia and nephrotoxicity observed in 3%, 9%, 11% and 4% of the patients, respectively. Treatment discontinuation was noted in five out of 102 patients.

CONCLUSIONS

Peptide receptor radionuclide therapy is a safe and efficacious treatment option for advanced PPGLs and may be considered a viable alternative to chemotherapy and I-¹³¹ MIBG.

Pheochromocytomas and Paragangliomas

Pheochromocytomas are rare neuroendocrine tumors. Extra-adrenal lesions arising from the autonomic neural ganglia are termed paraganglioma. Clinical symptoms are common between the adrenal and extra-adrenal forms and are determined by excess secretion of catecholamines. Hypertension is a critical and often dramatic feature of pheochromocytoma/paraganglioma, and its most prevalent reported symptom. However, given the rare occurrence of this cancer, in patients undergoing screening for hypertension, the prevalence ranges from 0.1% to 0.6%. Still, patients frequently come to the attention of endocrinologist when pheochromocytoma/paraganglioma is suspected as a secondary cause of hypertension. This article summarizes current clinical approaches in patients with pheochromocytoma/paraganglioma.

Asymptomatic left posterior mediastinal functional paraganglioma: A case report

RATIONALE

Paraganglioma refers to a set of neuroendocrine tumors derived from the chromaffin cells of the adrenal diplomatic ganglion. Paragangliomas can be classified as functional or nonfunctional based on the ability to synthesize and release catecholamines.

PATIENT CONCERNS

We report a 47-year-old man with a functional paraganglioma in the left posterior mediastinum and highlight the key elements of management of mediastinal paragangliomas.

DIAGNOSES

A left posterior mediastinal mass was found by computed tomography (CT) scan and Chest-enhanced CT. Preoperative ultrasound-guided biopsy suggested the possibility of a paraganglioma. A diagnosis of paraganglioma was established by immunohistochemistry.

INTERVENTIONS

The patient underwent single-stage resection of the lesion via left thoracotomy after preoperative oral α-adrenoceptor (phenoxybenzamine) therapy and intravenous fluid resuscitation for two weeks.

OUTCOMES

The postoperative period was uneventful. The patient exhibited no abnormal blood pressure or recurrence during the 12-month follow-up period.

LESSONS SUBSECTIONS AS PER STYLE

Pathological examination alone cannot determine whether it was a benign or malignant paraganglioma, which can be determined by pathological examination combined with distant metastasis. Long-term follow-up is required to assess the treatment effect.

Metastatic pheochromocytoma and paraganglioma: recent advances in prognosis and management

PURPOSE OF REVIEW

Metastatic pheochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors with variable prognosis. This review highlights recent studies on outcomes and management of patients with metastatic PPGL.

RECENT FINDINGS

Latest advances were made in identifying predictors of favorable outcomes of patients with metastatic PPGL. Recent studies evaluated the efficacy of tyrosine kinase inhibitors, high-specific-activity radiopharmaceuticals, and peptide receptors radionuclide therapy in treatment of metastatic disease. Moreover, ongoing studies are assessing the effects of hypoxia-inducible factor 2αα and heat shock protein 90 inhibitors as potential therapies.

SUMMARY

Several active studies are evaluating the efficacy of systemic chemo, immuno, radiopharmaceutical, and peptide receptor radionuclide therapies to relieve local and adrenergic symptoms and provide survival benefit for patients with symptomatic and/or progressive advanced metastatic PPGL. Owing to rarity and wide-outcome variability, multidisciplinary team effort and personalized approach are central in caring for patients with metastatic PPGL.

Rectal Paraganglioma

A 57-year-old woman was admitted with lower abdominal pain and bloody bowel discharge. She was diagnosed with rectal tumor by colonoscopy, and a biopsy was performed. Surgery was performed, resulting in a diagnosis of rectal paraganglioma. Since recurrence was confirmed three years later, reoperation was done, and chemotherapy with cyclophosphamide, vincristine and dacarbazine (CVD) was subsequently carried out for further recurrence. After the administration of up to 15 courses of CVD, we delivered best supportive care due to disease progression. She died a year and a half after starting chemotherapy. We herein report this rare disease with a review of the relevant literature.

Primary malignant tumors of the adrenal glands

Malignancy must be considered in the management of adrenal lesions, including those incidentally identified on imaging studies. Adrenocortical carcinomas (ACCs) are rare tumors with an estimated annual incidence of 0.7-2 cases per year and a worldwide prevalence of 4-12 cases per million/year. However, a much higher incidence of these tumors (>15 times) has been demonstrated in south and southeastern Brazil. Most ACCs cause hypersecretion of steroids including glucocorticoids and androgens. ACC patients have a very poor prognosis with a 5-year overall survival (OS) below 30% in most series. Pheochromocytoma or paraganglioma (PPGL) is a metabolically active tumor originating from the chromaffin cells of the adrenal medulla. The incidence of PPGL is 0.2 to 0.9 cases per 100,000 individuals per year. Pheochromocytomas are present in approximately 4-7% of patients with adrenal incidentalomas. Classically, PPGL manifests as paroxysmal attacks of the following 4 symptoms: headaches, diaphoresis, palpitations, and severe hypertensive episodes. The diagnosis of malignant PPGL relies on the presence of local invasion or metastasis. In this review, we present the clinical and biochemical characteristics and pathogenesis of malignant primary lesions that affect the cortex and medulla of human adrenal glands.

Treatment responses to antiangiogenetic therapy and chemotherapy in nonsecreting paraganglioma (PGL4) of urinary bladder with SDHB mutation: A case report

INTRODUCTION

Paraganglioma (PGL) is a rare neuroendocrine tumor. Currently, the malignancy is defined as the presence of metastatic spread at presentation or during follow-up. Several gene mutations are listed in the pathogenesis of PGL, among which succinate dehydrogenase (SDHX), particularly the SDHB isoform, is the main gene involved in malignancy. A 55-year-old male without evidence of catecholamine secretion had surgery for PGL of the urinary bladder. After 1 year, he showed a relapse of disease and demonstrated malignant PGL without evidence of catecholamine secretion with a germline heterozygous mutation of succinate dehydrogenase B (SDHB). After failure of a second surgery for relapse, he started medical treatment with sunitinib daily but discontinued due to serious side effects. Cyclophosphamide, vincristine, and dacarbazine (CVD) chemotherapeutic regimen stopped the disease progression for 7 months.

CONCLUSION

Malignant PGL is a very rare tumor, and SDHB mutations must be always considered in molecular diagnosis because they represent a critical event in the progression of the oncological disease. Currently, there are few therapeutic protocols, and it is often difficult, as this case demonstrates, to decide on a treatment option according to a reasoned set of choices.

[Primary thyroid paraganglioma: a case report]

Primary thyroid paraganglioma (PTPG) is rare,we report a case of 55 years old women with PTPG, which describes the clinical features, diagnosis and treatment. A possible diagnosis, treatment and follow-up strategy was proposed by reviewing relevant reports. It aims to improve the cognitive of PTPG and standardize its treatment.

Pheochromocytomas and Hypertension

PURPOSE OF REVIEW

Pheochromocytomas and paragangliomas (PPGLs) are uncommon catecholamine-producing neuroendocrine neoplasms that usually present with secondary hypertension. This review is to update the current knowledge about these neoplasms, the pathophysiology, genetic aspects and diagnostic and therapeutic algorithms based on scientific literature mostly within the past 3 years.

RECENT FINDINGS

Eighty to eighty-five percent of PPGLs arise from the adrenal medulla (pheochromocytomas; PCCs) and the remainder from the autonomic neural ganglia (paragangliomas; PGLs). Catecholamine excess causes chronic or paroxysmal hypertension associated with sweating, headaches and palpitations, the presenting features of PPGLs, and increases the cardiovascular morbidity and mortality. Genetic testing should be considered in all cases as mutations are reported in 35-40% of cases; 10-15% of PCCs and 20-50% of PGLs can be malignant. Measurements of plasma-free metanephrines or 24-h urine-fractionated metanephrines help biochemical diagnosis with high sensitivity and specificity. Initial anatomical localization after biochemical confirmation is usually with computed tomography (CT) or magnetic resonance imaging (MRI). ¹²³Iodine metaiodobenzylguanidine (¹²³I-MIBG) scintigraphy, positron emission tomography (PET) or single-photon emission computed tomography (SPECT) is often performed for functional imaging and prognostication prior to curative or palliative surgery. Clinical and biochemical follow-up is recommended at least annually after complete tumour excision. Children, pregnant women and older people have higher morbidity and mortality risk. De-bulking surgery, chemotherapy, radiotherapy, radionuclide agents and ablation procedures are useful in the palliation of incurable disease. PPGLs are unique neuroendocrine tumours that form an important cause for endocrine hypertension. The diagnostic and therapeutic algorithms are updated in this comprehensive article.

Treatment and outcome of metastatic paraganglioma of the spine

BACKGROUND

Spinal metastatic paraganglioma (MPG) is rare and only reported in individual case reports. The low incidence makes it difficult to define appropriate therapy and prognosis. Our study illustrated the largest series to discuss the possible treatment and outcomes of patients with spinal MPG.

METHODS

A retrospective study of 15 patients with spinal MPG who were surgically treated between 2005 and 2014 was performed. Three surgical modalities were applied, and radiotherapy and chemotherapy were utilized as adjuvant therapy.

RESULTS

The mean patients age was 40.9 (range 23-58) years. The period between primary surgery and spinal metastasis averaged 8.2 (0.5-15) years. Lesions were mainly located in cervical spine (2), thoracic spine (8), lumbar spine (3), and sacrum (2). The mean follow-up period was 35.0 months. Lesion progression was detected in nine patients, whereas five patients (33.3%) passed away. For solitary spine, multiple bone and both bone and nonosseous metastasis cases, the mean progression-free survival was 41 (range 9-56), 22.5 (range 12-38) and 8.3 (range 3-18) months, respectively.

CONCLUSIONS

The cases presented in the current study highlight the crucial role of surgery. Total en bloc for solitary spinal MPG could result in a satisfying prognosis and piecemeal total resection with postoperative radiotherapy could be an alternative therapy. Radiotherapy and chemotherapy were advocated, especially for the multiple metastasis.

Malignant pheochromocytoma-paraganglioma: pathogenesis, TNM staging, and current clinical trials

PURPOSE OF REVIEW

Pheochromocytomas and paragangliomas (PPGs) are rare neuroendocrine tumors. Over the last 15 years, substantial progress has been made toward understanding the clinical aspects and molecular origins of this disease. Nevertheless, predicting and managing malignancy remains the biggest challenge in clinical practice. The natural history of patients with malignant PPGs has not yet been described, and their prognosis varies. Currently, the diagnosis of malignant PPGs relies on the presence of metastases, by which time the disease is usually advanced. Better understanding of the clinical and molecular characteristics of patients with malignant PPGs has spurred several prospective clinical trials.

RECENT FINDINGS

Several molecular targeted therapies, a novel radiopharmaceutical medication that targets the catecholamine transporter, and immunotherapy are under evaluation for the treatment of patients with malignant PPGs. Furthermore, the identification of clinical predictors of malignancy and survival has led to the first TNM staging classification for PPGs.

SUMMARY

Prospective clinical trials are providing patients with therapeutic options beyond systemic chemotherapy. The knowledge derived from these trials and from the evaluation of the TNM staging in clinical practice will help to clarify how to most effectively treat malignant PPGs.

PRECISION MEDICINE IN ADRENAL DISORDERS: THE NEXT GENERATION

OBJECTIVE

Discuss exciting new research in the area of adrenal disorders that has emerged in the last few years. Advances in genetics, biochemical diagnosis, and imaging modalities that have set new standards for diagnosis and treatment are described.

METHODS

A literature review was conducted on adrenal disorders using PubMed.

RESULTS

We highlight new developments in adrenal diseases from new genes discovered in aldosterone-producing adenomas, cortisol-producing tumors to pheochromocytomas/paragangliomas. In addition, we discuss new information regarding the question of whether nonfunctional adrenal adenomas are really functional or not. In congenital adrenal hyperplasia, emerging steroids that might be helpful in the near future for diagnostic purposes are discussed. New types of imaging are now available to identify endocrine neoplasms to help clinicians find lesions after biochemical confirmation.

CONCLUSION

The tremendous knowledge gained thus far in adrenal diseases sets the stage for not only new precision treatment modalities for individualized care but also for prevention.

ABBREVIATIONS

ACC = adrenal cortical carcinoma; APA = aldosterone-producing adenoma; APCC = aldosterone-producing cell cluster; CAH = congenital adrenal hyperplasia; CT = computed tomography; DOTATATE = [⁶⁸Ga]-DOTA(0)-Tyr(3)-octreotate; FDG = fluorodeoxyglucose; FH = fumarate hydratase; MR = miner-alocorticoid; MDH2 = malate dehydrogenase 2; PCC = pheochromocytoma; PET = positron emission tomography; PGL = paraganglioma; SCS = subclinical cortisol-secreting; SDHB = succinate dehydrogenase subunit B; TCGA = The Cancer Genome Atlas.

Is there an optimal preoperative management strategy for phaeochromocytoma/paraganglioma?

Phaeochromocytomas and paragangliomas (PPGLs) are catecholamine secreting neuroendocrine tumours that predispose to haemodynamic instability. Currently, surgery is the only available curative treatment, but carries potential risks including hypertensive and hypotensive crises, cardiac arrhythmias, myocardial infarction and stroke, due to tumoral release of catecholamines during anaesthetic induction and tumour manipulation. The mortality associated with surgical resection of PPGL has significantly improved from 20-45% in the early 20th century (Apgar & Papper, AMA Archives of Surgery, 1951, 62, 634) to 0-2·9% in the early 21st century (Kinney et al. Journal of Cardiothoracic and Vascular Anesthesia, 2002, 16, 359), largely due to availability of effective pharmacological agents and advances in surgical and anaesthetic practice. However, surgical resection of PPGL still poses significant clinical management challenges. Preoperatively, alpha-adrenoceptor blockade is the mainstay of management, although various pharmacological strategies have been proposed, based largely on reports derived from retrospective data sets. To date, no consensus has been reached regarding the 'ideal' preoperative strategy due, in part, to a paucity of data from high-quality evidence-based studies comparing different treatment regimens. Here, based on the available literature, we address the Clinical Question: Is there an optimal preoperative management strategy for PPGL?

[Endocrinology, what's new in 2016]

The European Society of Endocrinology has published this year a series of guidelines for hypoparathyroidism, the management of adrenal incidentalomas as well as for the long-term follow-up of patients operated on for a phaeochromocytoma/paraganglioma (PPGL). For hypoparathyroidism, guidelines insist on screening for chronic complications and monitoring treatment with calcium and vitamin D; the use of recombinant PTH may provide new opportunities for the future. Concerning adrenal incidentalomas, the panel of the guidelines primarily recommends non contrast CT for the evaluation of the risk of malignancy. Patients operated on for a PPGL, should be offered an individualized follow-up plan based on assessment of their risk of tumor recurrence.

[Diagnosis and management of metastatic pheochromocytoma and paraganglioma]

Pheochromocytoma (PHEO) and paraganglioma (PGL) are rare catecholamine-producing neuroendocrine tumors arising from adrenal medulla or extra-adrenal sympathetic and parasympathetic ganglia. Most of the PHEOs/PGLs are benign tumors, but metastatic disease is common, especially in patients with particular genetic background. Although PHEOs/PGLs were described more than a century ago, diagnosis and therapy of metastatic disease are still challenging. Advances in understanding molecular and metabolic changes associated with tumorigenesis lead us to identification of the background of these tumors. Novel information allowed for development of more precise diagnostic methods and molecular therapeutic targets identification, which will improve care of patients with metastatic PHEO/PGL.Key words: diagnostics - management - paraganglioma - pheochromocytoma - therapy.

Novel insights into the polycythemia-paraganglioma-somatostatinoma syndrome

Worldwide, the syndromes of paraganglioma (PGL), somatostatinoma (SOM) and early childhood polycythemia are described in only a few patients with somatic mutations in the hypoxia-inducible factor 2 alpha (HIF2A). This study provides detailed information about the clinical aspects and course of 7 patients with this syndrome and brings into perspective these experiences with the pertinent literature. Six females and one male presented at a median age of 28 years (range 11-46). Two were found to have HIF2A somatic mosaicism. No relatives were affected. All patients were diagnosed with polycythemia before age 8 and before PGL/SOM developed. PGLs were found at a median age of 17 years (range 8-38) and SOMs at 29 years (range 22-38). PGLs were multiple, recurrent and metastatic in 100, 100 and 29% of all cases, and SOMs in 40, 40 and 60%, respectively. All PGLs were primarily norepinephrine-producing. All patients had abnormal ophthalmologic findings and those with SOMs had gallbladder disease. Computed tomography (CT) and magnetic resonance imaging revealed cystic lesions at multiple sites and hemangiomas in 4 patients (57%), previously thought to be pathognomonic for von Hippel-Lindau disease. The most accurate radiopharmaceutical to detect PGL appeared to be [¹⁸F]-fluorodihydroxyphenylalanine ([¹⁸F]-FDOPA). Therefore, [¹⁸F]-FDOPA PET/CT, not [⁶⁸Ga]-(DOTA)-[Tyr3]-octreotate ([⁶⁸Ga]-DOTATATE) PET/CT is recommended for tumor localization and aftercare in this syndrome. The long-term prognosis of the syndrome is unknown. However, to date no deaths occurred after 6 years follow-up. Physicians should be aware of this unique syndrome and its diagnostic and therapeutic challenges.

Diagnostic and Therapeutic Difficulties in Carotid Body Paragangliomas, Based on Clinical Experience and a Review of the Literature

BACKGROUND

Paragangliomas are rare neuroendocrine tumors, representing 0.03% of all tumors. Half of them develop in the head and neck, and among these 50% are sporadic cervical tumors.

OBJECTIVES

The aim of the study was to carry out an epidemiological and clinical analysis of paraganglioma patients diagnosed and treated at the authors' clinics between 1985 and 2014.

MATERIAL AND METHODS

The medical data of 47 patients were analyzed. All the patients were qualified for surgery. In 43 cases (88%), simple resection of the tumor was performed, including 11 cases (22%) that additionally required vascular suturing, and 5 (10%) that required reconstruction of the internal carotid artery. Carotid vessel repair was performed by shortening the internal carotid artery in 3 cases (6%), using a saphenous vein graft in 2 cases (4%), and by creating an anastomosis between the external carotid artery and the distal portion of the internal carotid artery in one case (2%).

RESULTS

In 40 cases (82%), the course of treatment was uneventful. Three patients (6%) were reoperated because of symptoms of cerebral stroke. Palsy of the hypoglossal nerve occurred in 3 cases (6%), and facial nerve palsy in 2 patients (4%). Six patients (12%) developed postoperative hematomas in the wound. In all the cases, histopathological examinations confirmed carotid paraganglioma.

CONCLUSIONS

Cooperation with an otolaryngologist and vascular surgeon during surgery is recommended due to frequent damage to carotid vessels by carotid paragangliomas. Detection of the tumor in the early stages improves surgical treatment outcomes and reduces the number of complications. Regular postoperative check-ups are necessary due to possible occurrences of multiple tumors.

Endocrine tumors associated with the vagus nerve

The vagus nerve (cranial nerve X) is the main nerve of the parasympathetic division of the autonomic nervous system. Vagal paragangliomas (VPGLs) are a prime example of an endocrine tumor associated with the vagus nerve. This rare, neural crest tumor constitutes the second most common site of hereditary head and neck paragangliomas (HNPGLs), most often in relation to mutations in the succinate dehydrogenase complex subunit D (SDHD) gene. The treatment paradigm for VPGL has progressively shifted from surgery to abstention or therapeutic radiation with curative-like outcomes. Parathyroid tissue and parathyroid adenoma can also be found in close association with the vagus nerve in intra or paravagal situations. Vagal parathyroid adenoma can be identified with preoperative imaging or suspected intraoperatively by experienced surgeons. Vagal parathyroid adenomas located in the neck or superior mediastinum can be removed via initial cervicotomy, while those located in the aortopulmonary window require a thoracic approach. This review particularly emphasizes the embryology, molecular genetics, and modern imaging of these tumors.

European Society of Endocrinology Clinical Practice Guideline for long-term follow-up of patients operated on for a phaeochromocytoma or a paraganglioma

Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours. Standard treatment is surgical resection. Following complete resection of the primary tumour, patients with PPGL are at risk of developing new tumoural events. The present guideline aims to propose standardised clinical care of long-term follow-up in patients operated on for a PPGL. The guideline has been developed by The European Society of Endocrinology and based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) principles. We performed a systematic review of the literature and analysed the European Network for the Study of Adrenal Tumours (ENS@T) database. The risk of new events persisted in the long term and was higher for patients with genetic or syndromic diseases. Follow-up in the published cohorts and in the ENS@T database was neither standardised nor exhaustive, resulting in a risk of follow-up bias and in low statistical power beyond 10 years after complete surgery. To inform patients and care providers in this context of low-quality evidence, the Guideline Working Group therefore prepared recommendations on the basis of expert consensus. Key recommendations are the following: we recommend that all patients with PPGL be considered for genetic testing; we recommend assaying plasma or urinary metanephrines every year to screen for local or metastatic recurrences or new tumours; and we suggest follow-up for at least 10 years in all patients operated on for a PPGL. High-risk patients (young patients and those with a genetic disease, a large tumour and/or a paraganglioma) should be offered lifelong annual follow-up.

MANAGEMENT OF CATECHOLAMINE-SECRETING TUMORS IN PREGNANCY: A REVIEW

OBJECTIVE

Catecholamine-secreting tumors (pheochromocytomas and paragangliomas) presenting during pregnancy are extremely rare, but they can be fatal to both mother and fetus. Recent discoveries in the genetic background of these tumors are expected to address an increasing number of at-risk women to prenatal diagnosis.

METHODS

The literature was reviewed in order to provide clinicians with a practical and updated guide on how to manage this life-threatening condition.

RESULTS

The clinical presentation of catecholamine-secreting tumors can be deceptive and mimic common disorders of pregnancy. Silent catecholamine-secreting tumors can become evident during pregnancy, and hypertension cannot be considered a hallmark for this condition: some women may be normotensive or develop orthostatic hypotension. Biochemical screening includes measurement of plasma free metanephrines or urinary fractioned metanephrines. Measurement of catecholamines, dopamine, and methoxytyramine can provide further information on tumor biology, location, and prognosis. Diagnostic imaging is limited, and medical treatment requires a cautious balance between hemodynamic control and effects on the fetoplacental unit. Several genes have been associated with syndromes including catecholamine-secreting tumors, and positive genetic testing can correlate with tumor behavior. Timing and modalities for tumor removal and delivery, including anesthetic management, depend on gestational age, maternal and fetal wellbeing, control of catecholamine excess, suspicion of multiple or malignant disease, and surgical accessibility to the tumor.

CONCLUSION

A timely diagnosis and a multidisciplinary approach are the keys to improve pregnancy outcomes in patients with a catecholamine-secreting tumor; each case should be managed in a tertiary referral center.

Pheochromocytoma and Paraganglioma: Genetics, Diagnosis, and Treatment

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare but unique neuroendocrine tumors. The hypersecretion of catecholamines from the tumors can be associated with high morbidity and mortality, even when tumors are benign. Up to 40% of PCCs/PGLs are associated with germline mutations in susceptibility genes. About one-quarter are malignant, defined by the presence of distant metastases. Treatment options for unresectable metastatic disease, including chemotherapy, (131)I-MIBG, and radiation, can offer limited tumor and hormone control, although none are curative. This article reviews the inherited genetics, diagnosis, and treatment of PCCs and PGLs.

15 YEARS OF PARAGANGLIOMA: Clinical manifestations of paraganglioma syndromes types 1-5

The paraganglioma (PGL) syndromes types 1-5 are autosomal dominant disorders characterized by familial predisposition to PGLs, phaeochromocytomas (PCs), renal cell cancers, gastrointestinal stromal tumours and, rarely, pituitary adenomas. Each syndrome is associated with mutation in a gene encoding a particular subunit (or assembly factor) of succinate dehydrogenase (SDHx). The clinical manifestations of these syndromes are protean: patients may present with features of catecholamine excess (including the classic triad of headache, sweating and palpitations), or with symptoms from local tumour mass, or increasingly as an incidental finding on imaging performed for some other purpose. As genetic testing for these syndromes becomes more widespread, presymptomatic diagnosis is also possible, although penetrance of disease in these syndromes is highly variable and tumour development does not clearly follow a predetermined pattern. PGL1 syndrome (SDHD) and PGL2 syndrome (SDHAF2) are notable for high frequency of multifocal tumour development and for parent-of-origin inheritance: disease is almost only ever manifest in subjects inheriting the defective allele from their father. PGL4 syndrome (SDHB) is notable for an increased risk of malignant PGL or PC. PGL3 syndrome (SDHC) and PGL5 syndrome (SDHA) are less common and appear to be associated with lower penetrance of tumour development. Although these syndromes are all associated with SDH deficiency, few genotype-phenotype relationships have yet been established, and indeed it is remarkable that such divergent phenotypes can arise from disruption of a common molecular pathway. This article reviews the clinical presentations of these syndromes, including their component tumours and underlying genetic basis.

Paraganglioma in Pregnancy: A Case Series and Review of the Literature

CONTEXT

Pregnancies complicated by a pheochromocytoma or paraganglioma are very rare, being estimated to occur in 0.007% of all pregnancies. Both the well-being of the mother and fetus need to be considered, and management can be challenging. The optimal management of women with a pheochromocytoma or paraganglioma in pregnancy is not well established.

OBJECTIVE

The objective of the study was to assess whether there is a difference in fetal or maternal mortality between pheochromocytomas and paragangliomas in pregnancy.

DESIGN

We present an experience of eight pregnancies in four SDHB germline mutation-positive women with sympathetic paragangliomas, followed by a systematic review of the literature to compare the outcome of paragangliomas with that of pheochromocytomas occurring in pregnancy.

RESULTS

In our case series, favorable fetal and maternal outcomes were seen in all eight pregnancies. From the systematic review, maternal and fetal mortality were lower in women with paragangliomas, at 3.6% and 12% respectively, compared with 9.8% and 16% in women with pheochromocytomas.

CONCLUSION

Pregnant women with paragangliomas may be at a lower risk of adverse outcome than those with pheochromocytomas, but both maternal and fetal mortality rates are still higher than that of the general obstetric population.