Acute respiratory distress syndrome associated with a pheochromocytoma in an adult dog.

A 16-year-old castrated male shih tzu dog was brought to the emergency service because of an acute (24 h) history of gagging, coughing, and lethargy. Physical examination revealed dyspnea concurrent with diffuse, bilateral, pulmonary crackles and wheezes. Oxygen saturation, measured with a pulse oximeter, was < 95%. Thoracic radiographs revealed a multifocal alveolar pattern superimposed over a diffuse interstitial pattern with normal heart size. The dog continued to be dyspneic despite oxygen therapy. In accordance with the radiographic findings, further supportive care was recommended. Due to the unknown prognosis and financial constraints, the owner elected humane euthanasia. Necropsy confirmed a pheochromocytoma and lung changes without evidence of congestive heart failure. Findings were consistent with diffuse alveolar damage. These findings correlated with the dog's clinical diagnosis of acute respiratory distress syndrome (ARDS). No other disease processes associated with ARDS were identified. The purpose of this case report is to describe an unusual presentation of ARDS likely associated with a pheochromocytoma and confirmed by necropsy. Acute respiratory distress syndrome associated with a pheochromocytoma has been described in medical literature but has never been reported in veterinary medicine. Key clinical message: Pheochromocytomas should be added to the list of risk factors associated with ARDS in dogs. Dogs with a suspected diagnosis of pheochromocytoma whose owners elect against surgical removal should be closely monitored for an acute onset of respiratory distress, which could suggest the development of ARDS.

Syndrome de détresse respiratoire aiguë associé à un phéochromocytome chez un chien adulteUn chien shih tzu mâle castré de 16 ans a été amené aux services d'urgence en raison d'antécédents aigus (24 heures) de haut-le-coeur, de toux et de léthargie. L'examen physique a révélé une dyspnée concomitante à des crépitements et des respirations sifflantes diffuses, bilatérales et pulmonaires. La saturation en oxygène, mesurée avec un oxymètre de pouls, était < 95 %. Les radiographies thoraciques ont révélé un motif alvéolaire multifocal superposé à un motif interstitiel diffus avec une taille cardiaque normale. Le chien est resté dyspnéique malgré l'oxygénothérapie. Conformément aux résultats radiographiques, des soins de soutien supplémentaires ont été recommandés. En raison du pronostic inconnu et des contraintes financières, le propriétaire a opté pour l'euthanasie sans cruauté. La nécropsie a confirmé un phéochromocytome et des modifications pulmonaires sans signe d'insuffisance cardiaque congestive. Les résultats concordaient avec des lésions alvéolaires diffuses. Ces résultats étaient en corrélation avec le diagnostic clinique du syndrome de détresse respiratoire aiguë (ARDS) du chien. Aucun autre processus pathologique associé à l'ARDS n'a été identifié. Le but de ce rapport de cas est de décrire une présentation inhabituelle de l'ARDS probablement associée à un phéochromocytome et confirmée par la nécropsie. Le syndrome de détresse respiratoire aiguë associé à un phéochromocytome a été décrit dans la littérature médicale mais n'a jamais été rapporté en médecine vétérinaire.Message clinique clé:Les phéochromocytomes doivent être ajoutés à la liste des facteurs de risque associés à l'ARDS chez le chien. Les chiens avec un diagnostic suspecté de phéochromocytome dont les propriétaires choisissent de ne pas procéder à l'ablation chirurgicale doivent être étroitement surveillés pour détecter l'apparition aiguë d'une détresse respiratoire, ce qui pourrait suggérer le développement d'un ARDS.(Traduit par Dr Serge Messier).

[Diagnosis and management of patients with pheochromocytoma/paraganglioma: Consensus of experts of the Russian Medical Society for Arterial Hypertension and the Multidisciplinary Group for the Diagnosis and Treatment of Neuroendocrine Tumors].

The understanding of the nature of catecholamine-secreting tumors has changed significantly in recent years, affecting terminology and classification. Phaeochromocytoma/paraganglioma (PCC/PG) is a rare neuroendocrine tumor from chromaffin tissue that produces and secretes catecholamines. The incidence of PCC/PG is relatively low, with 2-8 cases per 1 million population per year; among patients with arterial hypertension, their prevalence is 0.2-0.6%. However, delayed diagnosis of PCC/PG is associated with a high risk of cardiovascular complications and a high mortality rate. The consensus presents the clinical manifestations of the disease with an emphasis on the course of arterial hypertension as the most common symptom in PCC/PG; modern ideas about the features of diagnosis, aspects of preoperative preparation, treatment, and follow-up of patients with PCC/PG are considered.

Effectiveness of Robot-assisted Adrenalectomy for a Giant Adrenal Hemangioma: A Case Report.

BACKGROUND: Adrenal hemangiomas are extremely rare benign tumors that often need to be distinguished from malignancies. Adrenal tumors >4 cm in size are treated surgically because the possibility of malignancy cannot be ruled out. Traditionally, open surgery has been the mainstay of treatment; however, in recent years, robot-assisted surgery has been increasingly used for tumors of larger size and suspected malignancy. Here, we report a case of robot-assisted adrenalectomy for an 11 cm adrenal hemangioma. CASE REPORT: A 62-year-old male with lateral abdominal pain was referred to our hospital for further examination and treatment. His medical history was significant for hypertension, diabetes, and dyslipidemia. Computed tomography revealed an 11 cm left adrenal tumor, and all endocrinological screening tests were negative. Because the possibility of malignancy could not be ruled out, a robot-assisted adrenalectomy was performed. The operation time was 129 min, and the estimated blood loss was 7 ml. Pathological findings revealed an adrenal hemangioma. The postoperative course was uneventful, and patient's condition subsequently improved postoperatively. CONCLUSION: Robot-assisted adrenalectomy was performed for a giant adrenal hemangioma without any complications. Robotic surgery is useful for resecting adrenal hemangiomas even exceeding 11 cm in diameter.

[The value of serum dehydroepiandrosterone sulfate in the functional evaluation of adrenal space-occupying lesions in adults].

Objective: To evaluate the function of serum dehydroepiandrosterone sulfate (DHEAS) in adult adrenal space-occupying lesions. Methods: In this cross-sectional study, 395 patients with adrenal space-occupying lesions who had their DHEAS levels measured were collected from the First Medical Center of Chinese PLA General Hospital from January 2010 to June 2021. They were divided into the adrenal Cushing syndrome (ACS) group (n=100) and non-ACS group (n=295). The former was divided into the cortisol-producing adrenal adenoma (CPA) group (n=67) and primary bilateral macronodular adrenal hyperplasia (PBMAH) group (n=33). Clinical data of each group were collected and compared among groups by independent samples t-test, chi-square test, and Mann-Whitney U test. Serum DHEAS ratio corrected for age and sex was further constructed to identify the receiver operating characteristic curve and the optimal tangent point value for different adrenal occupation. Results: Patients in the ACS group were younger (44.9±13.7 vs. 49.9±12.5, P=0.001); had a larger proportion of women (79/100 vs.139/295, P=0.001); and had higher cortisol levels [8∶00Am, 497.31 (343.52, 606.50) vs. 353.11 (267.50, 487.91) nmol/L, P<0.001] than those in the non-ACS group. The serum DHEAS level and ratio in the ACS group were significantly lower than those in the non-ACS group [0.50 (0.40, 1.21) vs. 2.68 (1.56, 4.32) µmol/L, 1.00 (0.43, 1.68) vs. 3.17 (2.21, 4.54), both P<0.001]. When the serum DHEAS ratio cut-off point was 1.29, the sensitivity and specificity for differential diagnosis of ACS and non-ACS were 72.0% and 91.5% respectively. The ratio of DHEAS in the CPA group was lower [0.58 (0.27, 1.05) vs. 1.14 (1.04, 2.40), P<0.001] than that in the PBMAH group. When the serum DHEAS ratio cut-off point was 0.99, the sensitivity and specificity for differential diagnosis of CPA and PBMAH were 64.2% and 81.2% respectively. Conclusion: Corrected age-sex DHEAS ratio can assist in the functional assessment of adrenal space-occupying lesions.

Characteristics of Adrenal Hemorrhage: A Single Clinic's Experience.

<b>Introduction:</b> Adrenal hemorrhage (AH) is a very rare and potentially life-threatening disease which may be secondary to trauma or of non-traumatic etiology.<b>Aim:</b> The aim of the study was to present the characteristics and management of adrenal hemorrhage and show that adrenal hemorrhage is more common than expected and that the clinical symptoms are not specific.<b>Materials and methods:</b> This retrospective study involved 199 patients with postoperative diagnosis of adrenal hemorrhage.<b>Discussion:</b> The factors identified as potential causes of adrenal hemorrhage are adrenocortical carcinoma, pheochromocytoma, and adrenal adenoma. The study group included 199 patients with postoperative diagnosis of AH. It showed that all patients with postoperative diagnosis had pheochromocytoma (n = 54), adrenal adenoma (n = 68), or adenocarcinoma (n = 17). If we look more careful at the results, we can find only 30% of patients (n = 39) with preoperative diagnosis of AH. This group of 39 patients was prepared for expedited surgery. In this group of patients, the preoperative diagnosis of AH was pheochromocytoma 28% (n = 11), adenocarcinoma (n = 4), and adrenal adenoma (n = 9).<b>Conclusions:</b> Bleeding into adrenal tumors is still an insufficiently understood topic due to its unpredictability and, as can be seen in our material, of varying severity. Out of 199 patients, only 30% (n = 39) were prepared for surgery with a preoperative diagnosis of AH; most of them had pheochromocytoma. We suggest that is very important to prepare patients for surgery with a preoperative diagnosis of AH using α-adrenoreceptor antagonists. Prolongation of the diagnostic process (time between the imaging examination and the surgery) may result in the disease progressing and adrenal bleeding.

A rare association of pheochromocytoma, paraganglioma, and pituitary adenoma (3PA): A case report and literature review.

RATIONALE: 3P association (3PA) is a rare condition with co-occurrence of pituitary adenoma and pheochromocytoma/paraganglioma. There have been less than a hundred documented cases of 3PA, which can be sporadic or related to genetic mutations. The present case report describes the first Iranian patient with 3PA and a 90th case of 3PA in the available literature. PATIENT CONCERNS AND INTERVENTIONS: A 36-year-old Caucasian male was admitted with headache and sudden increase in blood pressure. An abdominal CT scan revealed a retroperitoneal mass posterior to the inferior vena cava, later removed and diagnosed as a pheochromocytoma. Four years later, he noticed occasional mild headaches and a painless mass on the right side of his neck. The ultrasonography evaluations suggested a carotid body tumor, which was surgically removed. About a month after his second surgery, the severity of the patient's headaches worsened, and he developed right homonymous hemianopia. A brain MRI showed a mass in favor of macroadenoma, craniopharyngioma, or meningioma, and elevated prolactin level led to the diagnosis of macroprolactinoma. DIAGNOSES: Based on the provided history, this patient was diagnosed with 3PA, and a genetic study identified a positive succinate-dehydrogenase-complex subunit b mutation, possibly linked to his family history of carotid body tumor. OUTCOMES: He has remained symptom-free during his visits every 3 months. LESSONS: The number of cases diagnosed with 3PA worldwide is increasing. Using clinical and genetic assessments, we can timely diagnose and adequately monitor individuals with or at risk of 3PA.

Acute onset of hypertensive encephalopathy in a dog with right adrenal pheochromocytoma and neoplastic invasion of the caudal vena cava: Case report and review of the literature.

Background: Canine pheochromocytomas (PCCs) are rare tumors of the adrenal medulla. Clinical signs are often vague, resulting in intermittent catecholamine over secretion or neoplastic invasion of adjacent structures. Case Description: A 12-year-old Epagneul Breton dog with a 1-year history of chronic kidney disease, was examined for acute onset of severe neurological signs. Based on clinical and instrumental data, hypertensive encephalopathy was suspected. Cardiac and abdominal ultrasound were performed. Severe hypertensive cardiopathy and a right adrenal gland mass with invasion of the caudal vena cava were diagnosed. Computed tomography imaging confirmed the suspect of invasive malignant neoplasia. Emergency pharmacological therapy was started to reduce systemic pressure, improve clinical signs, and stabilize the dog in view of surgical resolution. After initial improvement, patient conditions abruptly worsened, and euthanasia was elected. Histology examination confirmed a right adrenal PCC, with caval invasion. Conclusion: To the authors' conclusions, acute hypertensive encephalopathy is a peculiar manifestation of PCCs. Ultrasound is a useful, and rapid test to suspect PCC as it can detect adrenal alterations, caval invasion, metastasis, and cardiac sequelae consistent with the condition. PCC can mimic multiple affections, and be misinterpreted, especially when a concurrent disease has already been diagnosed. Veterinarians need to be aware that comorbidities could mask clinical signs and delay diagnosis. Furthermore, this clinical case reminds us to include PCC also in the differential diagnosis of dogs with an acute onset of severe neurological signs.

Uncommon adrenal rest tumors and massive adrenal enlargement in adult with congenital adrenal hyperplasia mimicking metastasis from pleomorphic sarcoma.

BACKGROUND: Congenital adrenal hyperplasia (CAH) encompassed a bunch of autosomal recessive disorders characterized by impaired cortisol levels due to an enzymatic deficiency in steroid synthesis. In adult male patients with CAH, a frequent complication related to poor disease control is the development of ectopic adrenocortical tissue in the testes, named testicular adrenal rest tumors (TART). Conversely, ovarian adrenal rest tumors (OART) in females are extremely rare and adrenal rests in sites other than gonads are so uncommon to have been described only few times in literature. CASE PRESENTATION: We report a case of a male patient with untreated CAH and oncologic history of pleomorphic sarcoma who presented with massive bilateral adrenal enlargement and adrenal rest tumors in peri-lumbar and peri-cecal sites, which mimicked metastasis from sarcoma. CONCLUSIONS: The development of massive adrenal enlargement and ectopic adrenal rest tumors in sites other than gonads, even if very uncommon, should be suspected in patients with CAH and prolonged periods of undertreatment.

Adrenal Pathologies.

Adrenal pathologies have variable clinical presentations and primary care providers should be aware of common and serious adrenal disorders. All adrenal masses require evaluation for malignancy, whether primary or metastatic, and all masses require evaluation for inappropriate hormonal secretion. In the event of adrenal insufficiency, the etiology of cortisol inadequacy must be identified and appropriately treated to prevent life-threatening complications.

Multiple Endocrine Neoplasia Type 1, Type 2A, and Type 2B.

Multiple endocrine neoplasia type 1 is a rare genetic neuroendocrine syndrome caused by over 1500 different germline mutations. It can cause 20 different endocrine tumors affecting primarily the parathyroid glands, gastroenteropancreatic tract, and the anterior pituitary gland. Multiple endocrine neoplasia type 2A (MEN2A) and Multiple endocrine neoplasia type 2B (MEN2B) are autosomal dominant genetic syndromes because of a germline variant in the 'rearranged during transfection' (RET) proto-oncogene. There are common RET mutations causing receptor hyperactivation and induction of downstream signals that cause oncogenesis. Common conditions with MEN2A are medullary thyroid cancer (MTC), pheochromocytoma, and primary hyperparathyroidism. Common conditions with MEN2B include MTC, pheochromocytomas, and benign ganglioneuromas.

Neuroendocrine Neoplasms.

Neuroendocrine neoplasms (NENs), also known as neuroendocrine tumors (NETs), are rare tumors derived from cells with characteristics of both nerve and endocrine cells. The clinical presentation, diagnosis, and treatment of NENs vary significantly depending on the type, location, whether the neoplasm is hormonally functional, how aggressive it is, and whether it has metastasized to other parts of the body. This article provides an overview of specific types of NETs, clinical presentations and related syndromes, diagnosis, and approach to management of common NENs.

Management of a giant adrenal schwannoma.

In this case report, we present a man in his 60s who presented with an incidentally discovered right adrenal mass, which turned out to be an adrenal schwannoma. This is a very rare tumour that originates from Schwann cells and involves the peripheral nerves. The tumour was removed by open adrenalectomy, and this 15-cm adrenal schwannoma is one of the largest reported in the literature, with none >16 cm having ever been reported. This case highlights the importance of keeping an open mind about the cause of an incidentally discovered adrenal mass, which is an increasingly common way for adrenal tumours to present given the increased access to cross-sectional imaging. As well as presenting the case and the pathological basis behind adrenal schwannomas, we include a review of the literature and a general discussion about incidentally discovered adrenal masses.

Pheochromocytoma/paraganglioma type 5 syndrome as a cause of secondary hypertension in a Colombian patient: case report / Síndrome de feocromocitoma-paraganglioma de tipo 5 como causa de hipertensión arterial en una paciente colombiana: reporte de caso

Pheochromocytoma is a tumor derived from neural crest cells able to produce sympathomimetic substances and, hence, a particular clinical picture. It is responsible for less than 1% of high blood pressure cases, with an estimated incidence between 0.4 and 0.6 cases per 100,000 people each year, and an average survival of seven years. Pheochromocytoma is a solid tumor with a high genetic component, as heritability can reach 40%. Once diagnosed, its treatment and prognosis are partly conditioned by the associated pathogenic variants that can be documented, especially those related to RET, SDHx, VHL, and NF1 genes. We present the case of a young woman with abdominal pain and high blood pressure, who was found to have a pheochromocytoma. Genetic testing detected a rare and recently discovered pathogenic variant: the SDHA:c.1A>C (p.Met1Leu). The patient responded adequately to the surgical treatment and continued the follow-up without documented recurrences. The diagnostic approach for pheochromocytoma patients must start with a clinical suspicion, followed by metabolite measurement in blood and urine, and finally, imaging. Currently, technology development allows precision medicine applicability. In this case of pheochromocytoma, recent developments in precision medicine resulted in the detection of associated genetic components involving the patient and her family. Adequate screening of the index patient is required for documenting pathogenic variants and better characterizing the disease.

El feocromocitoma es un tumor derivado de las células de la cresta neural con la capacidad de producir sustancias simpaticomiméticas y, por ende, un cuadro clínico particular. Causa menos del 1 % de los casos de hipertensión arterial sistémica y su incidencia se estima entre 0,4 y 0,6 casos por 100.000 personas cada año, con una supervivencia media de siete años. De todos los tumores sólidos, el feocromocitoma tiene un mayor componente genético, que puede heredarse hasta en el 40 % de los casos. Una vez diagnosticada la enfermedad, se debe definir el tratamiento y el pronóstico, en parte condicionados por las variantes genéticas asociadas, en especial RET, SDHx, VHL y NF1. Se presenta el caso de una mujer joven con dolor abdominal e hipertensión arterial sistémica, a quien se le diagnosticó feocromocitoma. Al secuenciar el exoma, se identificó una variante patogénica extremadamente rara y de reciente descubrimiento: SDHA: c.1A>C (p.Met1Leu). La paciente respondió adecuadamente al tratamiento quirúrgico y continuó en seguimiento sin recurrencias. El abordaje diagnóstico de los pacientes con feocromocitoma comienza con la sospecha clínica, seguida de la medición de determinados metabolitos en sangre y orina, y, finalmente, los estudios de imagenología. Los desarrollos tecnológicos actuales permiten la aplicación de la medicina de precisión en este campo. En este caso de feocromocitoma, se identificó un componente genético importante que no solo afecta al paciente, sino también, a sus familiares. La tamización adecuada del caso índice permite identificar mutaciones y caracterizar mejor la enfermedad.

Rare Case of Adrenal Hemangioma Discovered Incidentally during Renal Colic Investigation.

BACKGROUND Hemangiomas of the adrenal gland are rare benign non-functional tumors arising from the gland's vascular endothelium. Adrenal hemangiomas are rare in clinical settings, often discovered incidentally during an unrelated diagnostic investigation. CASE REPORT A 39-year-old man presented with a heterogeneous, enhancing 4.56×4.24×3.9-cm mass originating from the right adrenal gland's lateral limb, discovered incidentally on computed tomography (CT) to investigate renal colic. He was routinely followed up for 2 years with serial CT scans; the mass exhibited considerable growth compared with baseline, with a relatively stable appearance with hyperdense soft tissue component, fat, and foci of calcification. Dexamethasone suppression test demonstrated suppressed cortisol response, indicating a non-functional mass. Therefore, laparoscopic right adrenalectomy was performed, owing to the benign nature of the preoperative diagnosis of myelolipoma and mass size. The patient experienced an uneventful recovery, with no perioperative complications. The resected mass was 5×4×4 cm in size and weighed 30 g. Histopathology confirmed adrenal hemangioma. Serial sectioning revealed an encapsulated lesion with heterogeneous solid and cystic surfaces. Light microscopy examination showed dilated and congested vascular channels lined by flattened endothelium. Focal mature adipose tissue was seen. CONCLUSIONS The infrequent occurrence of adrenal hemangiomas and their nonspecific clinical and radiological presentation results in a considerable diagnostic challenge and, often, misdiagnosis. Surgical resection is usually necessary to exclude malignant disease, alleviate pressure-related symptoms, and decrease risk of retroperitoneum hemorrhage. These lesions are associated with a good prognosis. One limitation of this report is the lack of preoperative adrenal magnetic resonance imaging of the incidental adrenal mass.

Successful endoscopic approach for peripheral neuroblastic tumors in children.

BACKGROUND: Recently, reports of endoscopic approaches for neuroblastoma, ganglioneuroblastoma, and ganglioneuroma (peripheral neuroblastic tumor; PNTs) have been increasing. This study aimed to clarify the indications for endoscopic surgery for PNTs. METHODS: Pediatric patients who underwent endoscopic surgery for PNTs at our institution were included in this study. Image-defined risk factors (IDRFs) were analyzed using preoperative computed tomography (CT). RESULTS: Twenty-four patients underwent endoscopic surgery for PNTs. The diagnoses included neuroblastoma (n = 11), ganglioneuroma (n = 10), and ganglioneuroblastoma (n = 3). Regarding the tumor site, there were 18 cases of adrenal tumors, five cases of mediastinal tumors, and one case of retroperitoneal tumors. Image-defined risk factors were positive in eight cases (contacted with a renal vessel, n = 6; compression of principal bronchi, n = 2). Complete resection was accomplished in 21 cases (14 of 16 IDRF-negative cases and seven of eight IDRF-positive cases). All patients survived without recurrence during the follow-up period. CONCLUSIONS: The CT findings of contact with renal vessels and compression of principal bronchi do not seem to be indicators of incomplete resection. An endoscopic approach to PNTs in pediatric patients is feasible with a good prognosis if patients are selected strictly.

[Adrenal tumors: current standards in clinical management]. / Nebennierentumoren ­ aktuelle Standards im klinischen Management.

Adrenal tumors are among the most common tumors in humans. They are most frequently discovered incidentally during abdominal imaging for other reasons or due to clinical symptoms (e.g. Conn's or Cushing's syndrome, pheochromocytoma or androgen excess). Although over 80% of adrenal tumors are benign, in cases of hormone excess, they are associated with significantly increased morbidity. In highly malignant adrenocortical carcinoma (ACC), early diagnosis is of particular prognostic relevance. Therefore, this review presents the diagnostic procedure for what are referred to as adrenal incidentalomas and provide recommendations for the management of ACC and pheochromocytomas/paragangliomas (PPGL). In primary diagnosis, sufficient hormone diagnostics is required for all adrenal tumors, as this is the only way to identify all patients with relevant hormone excess. Imaging has increasingly improved in recent years and allows a reliable assessment of the tumor's malignancy in most cases. Imaging of first choice is unenhanced computed tomography (CT), while magnetic resonance imaging (MRI) and fluorodeoxyglucose-18 positron emission tomography (FDG-PET/CT) are reserved for special situations, as published evidence on these procedures is more limited. The treatment of ACC and PPGL is complex and is carried out on an interdisciplinary basis at specialized centers. In the case of localized disease, surgery is the only curative treatment option. There are now clear recommendations for individualized adjuvant therapy for ACC. In metastatic disease, mitotane with or without platinum-containing chemotherapy is the standard. Other lines of therapy should be discussed with a reference center. Over 35% of PPGL have a germline mutation; therefore, genetic testing should be offered. In metastatic PPGL, an individual decision is required between active surveillance, radionuclide therapy, sunitinib or chemotherapy.

[MAX germline mutation-associated pheochromocytoma-paraganglioma syndrome: multiple endocrine neoplasia type 5].

The individualized precision management of hereditary pheochromocytoma (PHEO) and paraganglioma (PGL) syndromes (PPGLs) based on molecular diagnosis and molecular subtype is becoming more popular. The newly discovered MAX germline mutation-associated PPGLs are autosomally dominant and rare. To raise awareness and explore the effective management of individual diagnosis and treatment, the relevant literature published between January 2011 and February was systematically reviewed. There were a total of 101 patients in the 77 families, involving all 5 exons, containing 44 types of MAX germline mutations and mostly concentrated in exons 3 and 4 (64.4%), the main mutations were nonsense mutations and missense mutations (72.3%), and some were large fragment deletions or insertions, intron variant, gene fusion mutations were relatively infrequent. Furthermore, about 10% of the patients had a paternal parent-of-origin effect. Among the 101 patients, 96 (95.0%) developed PHEO including 15 metastatic PHEO, 61 bilateral PHEO and 35 unilateral PHEO. The age of diagnosis was (31.7±10.9) years (range: 13 to 80 years). The male to female ratio was 1.2∶1. Eleven were accompanied with chest and abdominal PGL. Eight (7.9%) were accompanied by functional pituitary adenoma. And 12 (11.9%) developed other neuroendocrine tumors (NET), of which 8 were accompanied by PHEO, including 4 hyperparathyroidism, 1 gangliocytoma and neuroblastoma, 1 pancreatic NET, 1 medullary thyroid carcinoma and 1 C cell hyperplasia. Six presented concomitant non-NET, including 1 tongue squamous cell carcinoma, 1 papillary thyroid carcinoma, 1 prostate cancer, 1 renal oncocytoma, 1 breast cancer with renal oncocytoma, and 1 thoracic chondrosarcoma with multifocal adenocarcinoma of lung. The remaining 5 cases (5.0%), including 4 other NET (2 ganglioblastoma, 1 abdominal neuroblastoma and 1 pancreatic NET) and 1 asymptomatic child, did not present PHEO. The MAX germline mutation may cause a novel multiple endocrine neoplasia, which can be described as type 5. A comprehensive baseline assessment of neural crest cell-derived diseases such as PPGL, pituitary adenoma, hyperparathyroidism, and/or gangliocytoma (neuroblastoma) was recommended for all people with MAX germline mutations, and the risk of bilateral and/or metastatic PHEO should also be considered. In contrast, patients with PPGLs combined with other NET, such as functional pituitary adenoma, should undergo genetic testing and pedigree screening that includes at least the MAX gene.