Pheochromocytoma and Paraganglioma

Same-day comparative protocol PET/CT-PET/MRI [68 Ga]Ga-DOTA-TOC in paragangliomas and pheochromocytomas: an approach to personalized medicine

BACKGROUND

PET/MRI is an emerging imaging modality which enables the evaluation and quantification of biochemical processes in tissues, complemented with accurate anatomical information and low radiation exposure. In the framework of theragnosis, PET/MRI is of special interest due to its ability to delineate small lesions, adequately quantify them, and therefore to plan targeted therapies. The aim of this study was to validate the diagnostic performance of [⁶⁸ Ga]Ga-DOTA-TOC PET/MRI compared to PET/CT in advanced disease paragangliomas and pheochromocytomas (PGGLs) to assess in which clinical settings, PET/MRI may have a greater diagnostic yield.

METHODS

We performed a same-day protocol with consecutive acquisition of a PET/CT and a PET/MRI after a single [⁶⁸ Ga]Ga-DOTA-TOC injection in 25 patients. Intermodality agreement, Krenning Score (KS), SUVmax (Standard Uptake Value), target-to-liver-ratio (TLR), clinical setting, location, and size were assessed.

RESULTS

The diagnostic accuracy with PET/MRI increased by 14.6% compared to PET/CT especially in bone and liver locations (mean size of new lesions was 3.73 mm). PET/MRI revealed a higher overall lesion uptake than PET/CT (TLR 4.12 vs 2.44) and implied an upward elevation of the KS in up to 60% of patients. The KS changed in 30.4% of the evaluated lesions (mean size 11.89 mm), in 18.4% of the lesions it increased from KS 2 on PET/CT to a KS ≥ 3 on PET/MRI and 24.96% of the lesions per patient with multifocal disease displayed a KS ≥ 3 on PET/MR, that were not detected or showed lower KS on PET/CT. In 12% of patients, PET/MRI modified clinical management.

CONCLUSIONS

PET/MRI showed minor advantages over conventional PET/CT in the detection of new lesions but increased the intensity of SSRs expression in a significant number of them, opening the door to select which patients and clinical settings can benefit from performing PET/MRI.

An Uncommon Presentation of Pheochromocytoma in Neurofibromatosis Type 1 and the Importance of Long-Term Follow-Up

Neurofibromatosis type 1 (NFT1) is a disease caused by mutations in the tumor suppressor gene NF1. It is associated with a higher incidence of chromaffin cell tumors which are usually adrenal, unilateral and benign. The presence of these tumors during pregnancy is extremely rare and frequently associated with fatal outcomes. We report the case of a female patient with NFT1, who presented with paroxysmal spells of headache, palpitations, dizziness and pre-cordial discomfort, starting immediately after the delivery of her third child. Diagnostic work-up came to reveal a bilateral pheochromocytoma and the patient underwent bilateral adrenalectomy. Over 12 years after the initial surgery, metastatic disease was diagnosed, and a reintervention was performed. This is a rare presentation of bilateral malignant pheochromocytoma in a patient with NFT1, with postpartum occurrence of the first symptoms. This text focuses the important details and challenges found at each stage of diagnosis and follow-up.

Nuclear and mitochondrial DNA alterations in pheochromocytomas and paragangliomas, and their potential treatment

Mitochondrial DNA (mtDNA) alterations have been reported in different types of cancers and are suggested to play important roles in cancer development and metastasis. However, there is little information about its involvement in pheochromocytomas and paragangliomas (PCCs/PGLs) formation. PCCs and PGLs are rare endocrine tumors of the chromaffin cells in the adrenal medulla and extra-adrenal paraganglia that can synthesize and secrete catecholamines. Over the last 3 decades, the genetic background of about 60% of PCCs/PGLs involving nuclear DNA alterations has been determined. Recently, a study showed that mitochondrial alterations can be found in around 17% of the remaining PCCs/PGLs. In this review, we summarize recent knowledge regarding both nuclear and mitochondrial alterations and their involvement in PCCs/PGLs. We also provide brief insights into the genetics and the molecular pathways associated with PCCs/PGLs and potential therapeutical targets.

18 F-MFBG PET/CT Is an Effective Alternative of 68 Ga-DOTATATE PET/CT in the Evaluation of Metastatic Pheochromocytoma and Paraganglioma

PURPOSE

The current guidelines state that the functional imaging choice in the evaluation of metastatic pheochromocytoma and paraganglioma (PPGL) is 68 Ga-DOTATATE PET/CT. 18 F-meta-fluorobenzylguanidine ( 18 F-MFBG) is a new PET tracer and an analog of meta-iodobenzylguanidine (MIBG). This study aimed to compare 18 F-MFBG and 68 Ga-DOTATATE PET/CT in patients with metastatic PPGL.

PATIENTS AND METHODS

Twenty-eight patients with known metastatic PPGL were prospectively recruited for this study. All patients underwent both 18 F-MFBG and 68 Ga-DOTATATE PET/CT studies within 1 week. Lesion numbers detected were compared between these 2 studies.

RESULTS

18 F-MFBG PET/CT was positive for detecting metastases in all patients, whereas positive results of 68 Ga-DOTATATE PET/CT were in 27 (96.4%) patients. A total of 686 foci of metastatic lesions were detected by both 18 F-MFBG and 68 Ga-DOTATATE imaging. In addition, 33 foci of abnormal activity were only detected by 18 F-MFBG, whereas 16 foci were only shown on 68 Ga-DOTATATE PET/CT.

CONCLUSIONS

Our data suggest that 18 F-MFBG PET/CT is an effective imaging method in the evaluation of metastatic PPGL and could be alternative of 68 Ga-DOTATATE PET/CT in this clinical setting.

Bladder Paraganglioma Associated With Succinate Dehydrogenase A Mutation Presenting as Pelvic Pain

A 21-year-old female presented to the hospital with acute onset left pelvic pain that began while urinating. Ultrasound of the pelvis revealed a 1.7 cm structure within the bladder wall. Follow-up imaging with magnetic resonance imaging confirmed a 1.9 cm mass in the urinary bladder wall. Cystoscopy with transurethral resection was performed. Histopathology of the obtained tissue confirmed the diagnosis of paraganglioma. Laboratory evaluation revealed evidence of catecholamine excess with elevated urine norepinephrine, urine normetanephrine, and plasma free normetanephrine. Functional imaging with Ga-DOTATATE positron emission tomography-computed tomography (PET-CT) revealed increased uptake in the region of the known mass without findings of metastasis. Genetic testing revealed succinate dehydrogenase A mutation, consistent with paraganglioma syndrome 5. The patient was treated with alpha-adrenergic blockade prior to partial cystectomy. Urinary bladder paraganglioma is a rare entity. The diagnosis requires a high index of clinical suspicion due to variable presentation. Hypertension and other signs of catecholamine excess, especially in relation to micturition, are important clues. Despite evidence of catecholamine excess in most patients with bladder paraganglioma, the majority are diagnosed after biopsy, indicating a need for improved diagnostic strategies in this patient population. Early diagnosis and treatment are essential to prevent potentially lethal cardiac complications and tumor metastasis.

Influence of duration of preoperative treatment with phenoxybenzamine and secretory phenotypes on perioperative hemodynamics and postoperative outcomes in pheochromocytoma and paraganglioma

Objectives

Resection of pheochromocytoma and paraganglioma (PPGL) carries risks with perioperative hemodynamic instability. Phenoxybenzamine (PXB) is a commonly used α-blockade to prevent it. It is unclear whether lengthening the preoperative duration of PXB is better for hemodynamic stability and postoperative outcomes. Furthermore, different types of catecholamines have varying effects on perioperative hemodynamics. Thus, our study aimed to investigate the impact of the duration of preoperative preparation with PXB and secretory phenotypes of the patients on intraoperative hemodynamic stability and postoperative complications in PPGL.

Methods

Between Dec 2014 and Jan 2022, 166 patients with PPGL were operated on by the same team at Sun Yat-sen Memorial Hospital. They were divided into group A(1-14d), Group B(15-21d), and Group C(>21d) based on the duration of management with PXB and into the adrenergic and the noradrenergic phenotype group based on secretory profiles. Data on intraoperative hemodynamics and postoperative outcomes were collected and compared among groups.

Results

A total of 96 patients occurred intraoperative hemodynamic instability, and 24 patients had 29 postoperative complications related to the surgery. Among the 145 patients treated with PXB, no significant differences were found in the cumulative time outside the target blood pressure(6.67%[0-17.16%] vs. 5.97%[0-23.08%] vs. 1.22%[0-17.27%], p=0.736) or in the median total HI-score(42.00[30.00-91.00] vs. 89.00[30.00-113.00] vs. 49.00[30.00-93.00], p=0.150) among group A(n=45), B(n=51) and C(n=49). Multivariate analysis demonstrated that the level of plasma-free metanephrine(MN) was an independent risk factor for intraoperative hemodynamic instability. And the median cumulative time outside of the target blood pressure in the adrenergic phenotype group was significantly greater than that in the noradrenergic phenotype group(8.17%[0-26.22%] vs. 1.86%[0-11.74%], p=0.029). However, the median total HI-score(99.50[85.00-113.25] vs. 90.00[78.00-105.00], p=0.570) and postoperative outcomes showed no differences between the two groups.

Conclusions

A preoperative duration of nearly 14 days with PXB is sufficient for ensuring intraoperative hemodynamic stability in PPGL. And lengthening the preparation duration may not provide additional benefits in the era of widespread application and advanced techniques of laparoscopic surgery. Additionally, patients with the adrenergic phenotype are more prone to intraoperative hemodynamic instability than the noradrenergic phenotype. Thus, more attention should be given to the adrenergic phenotype during surgery.

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

Background

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

Patients and methods

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

Results

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

Conclusions

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

Trained immunity in monocyte/macrophage: Novel mechanism of phytochemicals in the treatment of atherosclerotic cardiovascular disease

Atherosclerosis (AS) is the pathology of atherosclerotic cardiovascular diseases (ASCVD), characterized by persistent chronic inflammation in the vessel wall, in which monocytes/macrophages play a key role. It has been reported that innate immune system cells can assume a persistent proinflammatory state after short stimulation with endogenous atherogenic stimuli. The pathogenesis of AS can be influenced by this persistent hyperactivation of the innate immune system, which is termed trained immunity. Trained immunity has also been implicated as a key pathological mechanism, leading to persistent chronic inflammation in AS. Trained immunity is mediated via epigenetic and metabolic reprogramming and occurs in mature innate immune cells and their bone marrow progenitors. Natural products are promising candidates for novel pharmacological agents that can be used to prevent or treat cardiovascular diseases (CVD). A variety of natural products and agents exhibiting antiatherosclerotic abilities have been reported to potentially interfere with the pharmacological targets of trained immunity. This review describes in as much detail as possible the mechanisms involved in trained immunity and how phytochemicals of this process inhibit AS by affecting trained monocytes/macrophages.

Surgical strategies of complicated pheochromocytomas/paragangliomas and literature review

Pheochromocytomas (PCC)/paragangliomas (PGL) are catecholamine (CA) -secreting neuroendocrine tumors, which are known as PPGL due to their histological and pathophysiological similarities. In addition to the typical triad of paroxysmal headache, palpitation, and sweating, PPGL may also be accompanied by symptoms and signs involving multiple organs and systems such as the cardiovascular system, digestive system, endocrine system, and nervous system. Currently, surgical resection is the first choice for PPGL. Safe and effective surgical management of complicated PPGL is the goal of clinical work. In this paper, we discuss this hot issue based on complicated PPGL cases, aiming to share our experience of the surgical management strategy of PPGL.

Other Less Prevalent Tumors of the Central Nervous System

The presented tumors in this chapter are somewhat very rare, and their management is still debated due to the scarcity of information about their cell of origin, behavior, and biology. Treatment options are still limited, but we are confident that in the near future by discovering the genetic and biological mechanisms that drive tumor growth we will be able to offer new target therapies that should be flanked by surgery, radiotherapy, and chemotherapeutic agents actually in use. The purpose of this chapter is to highlight the most important known characteristics of these tumors offering the chance to recognize the disease and then offer the best opportunity for treatment to patients. The 5th WHO Classification Central Nervous System features substantial changes by moving further to advance the role of molecular diagnostics in CNS tumor classification, but remaining rooted in other established approaches to tumor characterization, including histology and immunohistochemistry, and probably, the category of many tumors will change. Here, the most important characteristics of each neoplasm are summarized focusing on genetic mechanisms and molecular pathways, their histopathologic footprints, signs and symptoms, radiologic features, therapeutic approaches, and prognosis as well as follow-up protocols. Schematic classifications are also presented to offer a better understanding of the pathology.

Hemodynamic Instability during Surgery for Pheochromocytoma: A Retrospective Cohort Analysis

BACKGROUND

Perioperative hemodynamic instability is one of the most common adverse events in patients undergoing adrenalectomy for pheochromocytoma. The aim of this study was to analyze the impact of perioperative severe hemodynamic instability.

METHODS

We present a retrospective, single-center analysis in a major tertiary hospital of all consecutive patients undergoing elective adrenalectomy from 2005 to 2019 for pheochromocytoma. Severe perioperative hypertension and hypotension were evaluated, defined as changes in blood pressure larger than 30% of the preoperative patient-specific mean arterial pressure (MAP).

RESULTS

Unilateral adrenalectomy was performed in 67 patients. Intraoperative episodes of hemodynamic instability occurred in 97% of all patients (n = 65), severe hypertension occurred in 24 patients (36%), and severe hypotensive episodes occurred in 62 patients (93%). Patients with more than five severe hypotensive episodes (n = 29) received higher preoperative alpha-adrenergic blockades (phenoxybenzamine 51 ± 50 mg d^-1 vs. 29 ± 27 mg d^-1; p = 0.023) and had a longer mean ICU stay (39.6 ± 41.5 h vs. 20.6 ± 19.1 h, p = 0.015).

CONCLUSION

Intraoperative hypotensive, rather than hypertensive, episodes occurred during adrenalectomy. The occurrence of more than five hypotensive episodes correlated well with a significantly longer hospital stay and ICU time.

Pre- and peri-operative characteristics, complications and outcomes of patients with biochemically silent pheochromocytomas; a case series

PURPOSE

Pheochromocytomas are rare tumors and biochemically silent ones with normal catecholamine levels are even rarer. Up to date, biochemically inactive pheochromocytomas are poorly investigated. We aimed to systematically assess the pre- and peri-operative characteristics and the outcomes of patients with these tumors who had been treated and followed-up in 2 tertiary centers.

METHODS

Clinical, laboratory and imaging data, treatment outcomes and follow-up of biochemically silent pheochromocytoma patients were recorded.

RESULTS

Ten patients (5 men) [median age at diagnosis 52.5 years (24-72)] were included. Adrenal masses were incidentally discovered in all patients except from one who presented with pheochromocytoma-related manifestations. Twenty-four-hour urine metanephrine and normetanephrine levels were in the low-normal, normal and high-normal range in 4, 4 and 2 patients and in 1, 6 and 3 patients, respectively. Tumors were unilateral [median size 46 mm (17-125)] and high density on pre-contrast CT imaging or high signal intensity on T2-weighted MRI scans were found in all cases. Pre-operatively, 5 patients were treated with phenoxybenzamine [median total daily dose 70 mg (20-100)]. Intra-operatively, 4 patients developed hypertension requiring vasodilator administration and 8 developed hypotension; vasoconstrictors were required in 5 cases. One patient, not pre-operatively treated with phenoxybenzamine, developed Takotsubo cardiomyopathy. During a median 24-month (12-88) follow-up period, one patient had disease progression.

CONCLUSIONS

The majority (90%) of patients with biochemically silent pheochromocytomas developed hemodynamic instability during adrenal surgery. In patients with biochemically silent adrenal lesions and a high suspicion index for pheochromocytoma based on tumor imaging characteristics, pre-operative alpha-blockade treatment may be advisable.

A Rare Case of Thoracoabdominal Paraganglioma: A Case Report and Literature Review

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors. Pheochromocytomas are derived from chromaffin cells of the adrenal medulla, while paragangliomas arise from the extra-adrenal autonomic paraganglia. Paragangliomas can derive from either parasympathetic or sympathetic paraganglia. The majority of parasympathetic ganglia-derived paragangliomas are nonfunctional and symptoms arise from mass effect, while sympathetic paragangliomas are frequently functional and present with symptoms that result from catecholamine hypersecretion. Here, we present the case of a 19-year-old female with hypertension whose biochemical tests revealed elevated plasma and urinary levels of norepinephrine and normetanephrine. Imaging studies showed a left paravertebral mass which was surgically removed. Histopathology confirmed a paraganglioma. Total surgical resection remains the gold-standard treatment and a cure can be achieved; however, all tumors may harbor malignant potential, and a long-term biochemical and imaging follow-up is required in all patients. Screening for genetic germline mutations may be helpful in identifying patients with a higher risk of recurrence or of developing other primary tumors.

Left adrenal aldosteronism coexisting with left paraaortic paraganglioma presenting as bilateral adrenal and left paraaortic tumors- comprehensive adrenal evaluation aiding perfect management: a case report

BACKGROUND

Coexistence of a catecholamine-secreting tumor and an adrenal cortical tumor is quite rare which makes both diagnosis and management challenging. The purpose of this article is to describe the presence of this condition, share a stepwise approach for preoperative evaluation, and review the related literature.

CASE PRESENTATION

A 44-year-old male patient had a history of hypertension and aggravating hypokalemia for years. Abdominal computed tomography incidentally found concomitant bilateral adrenal and left para-aortic tumors. Comprehensive adrenal hormone tests revealed a high aldosterone renin ratio and mildly elevated 24-h urine vanillylmandelic acid and norepinephrine levels. Subsequently, a metaiodobenzylguanidine scan showed uptake over the left para-aortic tumor, and NP-59 adrenal scintigraphy showed uptake over the left adrenal tumor. Further confirmatory tests, including captopril suppression, irbesartan suppression, and saline infusion, all confirmed the diagnosis of hyperaldosteronism. Adrenal venous sampling following 2 months of preparation with an alpha blocker demonstrated a left aldosterone-producing adrenal adenoma. Combining hormonal analysis, imaging studies, and adrenal venous sampling, the patient was diagnosed with left adrenal aldosteronoma, right adrenal nonfunctional tumor, and left para-aortic paraganglioma (PGL). Accordingly, laparoscopic left adrenalectomy and left PGL excision were performed smoothly under alpha blocker maintenance. The pathology report confirmed left adrenal cortical adenoma and left para-aortic PGL. Postoperatively, the blood pressure, biochemical tests, and adrenal hormone assays returned to normal, and related symptoms disappeared and were relatively stable during the follow-up period of two years.

CONCLUSIONS

This is the first case of left para-aortic PGL coexisting with an ipsilateral aldosterone-producing adenoma presenting as a left para-aortic tumor associated with bilateral adrenal tumors. Awareness of the rarity of this coexistence can avoid unexpected disasters during the process of evaluation and management.

Locally invasive recurrence or metastasis of pheochromocytoma into the liver?—clinicopathological challenges

Pheochromocytomas (PCC) are rare and functional neuroendocrine tumors developing from adrenal chromaffin cells. Predicting malignant behavior especially in the absence of metastasis can be quite challenging even in the era of improved understanding of the molecular mechanisms involved in PCCs. Currently, two histopathological grading systems Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) and Grading of Adrenal Pheochromocytoma and Paraganglioma (GAPP) score are used in clinical practice, but these are subject to significant interobserver variability. Some of the most useful clinical factors associated with malignancy are large size ([4–5 cm), and genetic features such as presence of SDHB germline mutations. Local invasion is uncommon in PCC and metastasis seen in 10 to 17% but higher in germline mutations and when this occurs management can be challenging. Here, we report on a case with challenges faced by the pathologist and clinicians alike in diagnosis and management of PCC recurrence.

The use of temozolomide in paediatric metastatic phaeochromocytoma/paraganglioma: A case report and literature review

There is increasing evidence to support the use of temozolomide therapy for the treatment of metastatic phaeochromocytoma/paraganglioma (PPGL) in adults, particularly in patients with SDHx mutations. In children however, very little data is available. In this report, we present the case of a 12-year-old female with a SDHB-related metastatic paraganglioma treated with surgery followed by temozolomide therapy. The patient presented with symptoms of palpitations, sweating, flushing and hypertension and was diagnosed with a paraganglioma. The primary mass was surgically resected six weeks later after appropriate alpha- and beta-blockade. During the surgery extensive nodal disease was identified that had been masked by the larger paraganglioma. Histological review confirmed a diagnosis of a metastatic SDHB-deficient paraganglioma with nodal involvement. Post-operatively, these nodal lesions demonstrated tracer uptake on 18F-FDG PET-CT. Due to poor tumour tracer uptake on 68Ga-DOTATATE and 123I-MIBG functional imaging studies radionuclide therapy was not undertaken as a potential therapeutic option for this patient. Due to the low tumour burden and lack of clinical symptoms, the multi-disciplinary team opted for close surveillance for the first year, during which time the patient continued to thrive and progress through puberty. 13 months after surgery, evidence of radiological and biochemical progression prompted the decision to start systemic monotherapy using temozolomide. The patient has now completed ten cycles of therapy with limited adverse effects and has benefited from a partial radiological and biochemical response.

Succinate dehydrogenase-deficient malignant paraganglioma complicated by succinate dehydrogenase-deficient renal cell carcinoma

INTRODUCTION

SDH Gene mutation is known to be a common cause of pheochromocytoma/paraganglioma and renal cell carcinoma. Here, we report a case of succinate dehydrogenase B-deficient paraganglioma, which has a high risk of metastasis and recurrence, complicated by succinate dehydrogenase-deficient renal cell carcinoma, which is rare and accounts for approximately 0.1% of all renal cell carcinomas.

CASE PRESENTATION

A 50-year-old man underwent en bloc resection of a retroperitoneal tumor and the right kidney for retroperitoneal paraganglioma and right renal tumor. Both tumors showed negative expressions of succinate dehydrogenase B in immunostaining. The patient was diagnosed with succinate dehydrogenase-deficient paraganglioma and succinate dehydrogenase-deficient renal cell carcinoma. Seventeen months later, retroperitoneal lymphadenectomy revealed lymph node metastasis of the paraganglioma. Deletion of the SDHB gene was revealed by genome sequencing of the lymph node.

CONCLUSION

This is the first reported case of synchronously diagnosed succinate dehydrogenase-deficient paraganglioma and succinate dehydrogenase-deficient renal cell carcinoma.

Pheochromocytoma: A Case Report

Pheochromocytomas are rare tumors located in the adrenal medulla, that derives from the chromaffin cells and produce catecholamines. They are an uncommon cause of hypertension, and only 50% of the patients present symptoms compatible with this pathology. Here we describe the case of a 70-year-old woman with a history of anxiety, hypertension and palpitation, who had an unspecified nodule in the right adrenal gland. Laboratory studies revealed an elevated urinary metanephrines secretion. A diagnosis of pheochromocytoma was made and an adrenalectomy was performed. Our aim is to highlight the diagnosis of this rare tumor and how its early management can prevent morbidity and mortality.

Different intraoperative decisions for undiagnosed paraganglioma: Two case reports

BACKGROUND

Paragangliomas may be preoperatively misdiagnosed as non-functioning retroperitoneal tumors and are sometimes suspected only at the time of intraoperative manipulation. Without preoperative alpha blockade preparation, a hypertensive crisis during tumor manipulation and hypotension after tumor removal may result in critical consequences. Therefore, primary consideration should be given to the continuation or discontinuation of surgery on the basis of the possibility of gentle surgical manipulation and hemodynamic stabilization. We report two cases of paragangliomas detected intraoperatively.

CASE SUMMARY

A 65-year-woman underwent laparoscopic small-bowel wedge resection. A hypertensive crisis occurred during manipulation of the mass, and an unrecognized catecholamine-producing paraganglioma was suspected. The surgeon and anesthesiologists believed that tumor excision could be performed with minimal manipulation of the tumor because the tumor was in a favorable location. Serious hemodynamic instability did not occur with aggressive use of vasoactive drugs. A week later, a 54-year-man underwent open resection of a 3-cm-sized retroperitoneal mass and showed the same findings during mass manipulation. For this patient, continuous manipulation of the mass seemed inevitable due to adhesion between the right adrenal gland and the mass in a narrow surgical field. The surgeon and anesthesiologists decided to cancel the surgical procedure and planned to perform a reoperation after alpha blockade therapy. Two weeks later, the tumor was uneventfully removed with small doses of vasoactive drugs.

CONCLUSION

When an undiagnosed paraganglioma is suspected intraoperatively, reoperation after adequate preparation should be considered as an option to avoid fatal outcomes.

Non-Selective Alpha-Blockers Provide More Stable Intraoperative Hemodynamic Control Compared with Selective Alpha1-Blockers in Patients with Pheochromocytoma and Paraganglioma: A Single-Center Retrospective Cohort Study with a Propensity Score-Matched Analysis from China

PURPOSE

Alpha-adrenergic blockers are used in the preoperative preparation of patients with pheochromocytomas and paragangliomas (PPGLs) despite the controversial on perioperative hemodynamics. We aimed to determine whether selective or non-selective α-adrenergic blockers can provide better efficacy on patients' intraoperative hemodynamics.

PATIENTS AND METHODS

This single-center retrospective study was conducted in 2507 adult patients undergoing PPGL resections, patients received alpha-adrenergic receptor blockers as a binary variable (selective or non-selective). Propensity score matching was performed and 201 patients were matched successfully.

RESULTS

A total of 201 patients with PPGL were included in this study. The HI score scores were higher in the selective group than in the non-selective group (60.5 [44.5-84.0] vs 49.0 [37.0-67.25], P=0.027), as well as in the hemodynamic variables section [14.0 [8.0-20.0] vs 10 [6.0-16.0], P=0.009). In terms of specific indicators for each component, the lowest MAP in the selective group (55±10 mmHg vs 59±8 mmHg, P=0.038), the time to MAP below 60 mmHg (0.011% vs 0.022%, P=0.033) and the use of other vasoconstrictors (56.5% vs 35.5%, P=0.019) were significantly lower than in the non-selective group. Among the secondary outcome indicators, the incidence of intraoperative maximum SBP was significantly higher in the selective group than in the non-selective group (32.3% vs 11.3%, P=0.005). There were no significant differences in postoperative outcome indicators between the two groups.

CONCLUSION

In patients with PPGL, patients prepared preoperatively with non-selective alpha-blockers presented more stable hemodynamics intraoperatively compared to selective alpha1-blockers.

Bladder paraganglioma: basic characteristics and new perspectives on perioperative management

PURPOSE

Paraganglioma and pheochromocytoma are rare neuroendocrine tumors with severe metabolic and cardiovascular complications. Bladder PGLs are rare, and their clinical management is not precise. Here, we discuss the basic characteristics and perioperative management of bladder PGLs.

METHODS

We retrospectively reviewed 20 bladder PGL cases diagnosed at Sun Yat-sen University Cancer Center. Case notes were reviewed, clinical presentations, therapies, and outcomes were collected, and data analysis was performed.

RESULTS

Ten male and ten female patients with a median age of 47.5 years (range 14-69 years) were included. Most patients (65%) had no symptoms, and PGL was detected incidentally during medical checkups. All patients were treated surgically; 4 (20%) underwent transurethral resection of bladder tumor (TURBT), and 16 (80%) underwent partial cystectomy. Strong intraoperative blood pressure fluctuations were observed in 13 patients (65%). Two patients who were treated preoperatively with α-receptor blockers also experienced severe intraoperative blood pressure fluctuations. Postoperative measurements of troponin I were available for 3 patients, and all were significantly elevated. All patients were diagnosed with bladder PGL on postoperative pathological examination. The median follow-up time was 51 months (range 2-147 months), and 2 patients were lost to follow-up at 1 and 3 months; 16 (88.9%) survived without recurrence, 2 patients (11.1%) experienced recurrence, and 1 patient died.

CONCLUSION

Most bladder paragangliomas are easily mistaken for bladder urothelial carcinoma, and robust hemodynamic instability during surgery might be a challenge for urologists. Postoperative monitoring of troponin I, regardless of the presence of clinical symptoms, is recommended for patients with bladder PGL.

A Rare Case of a Right Atrial Paraganglioma in an Individual with the SHDB Mutation

Paragangliomas are extra-adrenal chromaffin cell tumors. A small percentage of these tumors can be found in the thoracic cavity and, when in the heart, are typically in the left atrium. In this case report, we discuss the case of an individual with a history of several paragangliomas with the SHDB mutation who was found to have two cardiac paragangliomas in the right atrium.

A 14-Year-Old Female With Chest Mass, Shortness of Breath, and Hypertension

BACKGROUND

A previously healthy 14-year-old girl was evaluated in the emergency department (ED) with 2 months of shortness of breath and fatigue.

METHODS

She initially presented to her primary pediatrician, where a complete blood count was only significant for mild anemia, thyroid function tests were normal, and a chest x-ray revealed a chest mass. This prompted her primary pediatrician to order a computed tomography scan and refer to the ED.

RESULTS

Her computed tomography scan confirmed a mediastinal mass versus necrotic lymphadenopathy. Her initial physical exam was unremarkable, except for hypertension. From the ED, she was admitted to the pediatric hospital medicine service. Infectious disease, oncology, and nephrology services were consulted to guide diagnostic evaluation.

CONCLUSIONS

Eventually, during her hospitalization, further history and workup led to a definitive diagnosis.

Long-term in vitro 2D-culture of SDHB and SDHD-related human paragangliomas and pheochromocytomas

The neuroendocrine tumours paraganglioma and pheochromocytoma (PPGLs) are commonly associated with succinate dehydrogenase (SDH) gene variants, but no human SDH-related PPGL-derived cell line has been developed to date. The aim of this study was to systematically explore practical issues related to the classical 2D-culture of SDH-related human paragangliomas and pheochromocytomas, with the ultimate goal of identifying a viable tumour-derived cell line. PPGL tumour tissue/cells (chromaffin cells) were cultured in a variety of media formulations and supplements. Tumour explants and dissociated primary tumour cells were cultured and stained with a range of antibodies to identify markers suitable for use in human PPGL culture. We cultured 62 PPGLs, including tumours with confirmed SDHB, SDHC and SDHD variants, as well as several metastatic tumours. Testing a wide range of basic cell culture media and supplements, we noted a marked decline in chromaffin cell numbers over a 4–8 week period but the persistence of small numbers of synaptophysin/tyrosine hydroxylase-positive chromaffin cells for up to 99 weeks. In cell culture, immunohistochemical staining for chromogranin A and neuron-specific enolase was generally negative in chromaffin cells, while staining for synaptophysin and tyrosine hydroxylase was generally positive. GFAP showed the most consistent staining of type II sustentacular cells. Of the media tested, low serum or serum-free media best sustained relative chromaffin cell numbers, while lactate enhanced the survival of synaptophysin-positive cells. Synaptophysin-positive PPGL tumour cells persist in culture for long periods but show little evidence of proliferation. Synaptophysin was the most consistent cell marker for chromaffin cells and GFAP the best marker for sustentacular cells in human PPGL cultures.

The surgical strategy of hormonally active primary cardiac paraganglioma sarcoma: A case report

Cardiac paraganglioma is a kind of rare neuroendocrine tumor characterized by the persistent secretion of catecholamines. Under excessive exposure of catecholamines, some atypical symptoms are presented, including hypertension, arrhythmias, and headache. The case of surgical treatment of a 28-year-old woman with primary cardiac paraganglioma is presented for experience sharing and surgical skill improvements.

Retroperitoneal paraganglioma with loss of heterozygosity of the von Hippel-Lindau gene: a case report and review of the literature

Von Hippel-Lindau (VHL) disease is an autosomal dominant disease related to germline mutations in VHL. In VHL disease, pheochromocytoma develops in 10%-20% of patients because of germline mutations and loss of heterozygosity of VHL. However, the rate of paraganglioma associated with VHL is low compared with that of pheochromocytoma, and the reason is unknown. In this study, we performed germline and somatic mutation analyses of retroperitoneal paraganglioma that developed in a patient with clinically diagnosed VHL disease and investigated the tumorigenic mechanism of paraganglioma. The patient was a 25-year-old woman who was considered to have VHL disease on the basis of her family history. She was referred to our clinic to investigate a tumor at the bifurcation of the common iliac artery. The tumor was diagnosed as retroperitoneal paraganglioma by clinical evaluations. A left renal cell carcinoma was also suspected. Polymerase chain reaction direct sequencing analysis and polymorphic microsatellite analysis within the VHL locus suggested that loss of heterozygosity of VHL was associated with paraganglioma and renal cell carcinoma. Multiplex ligation-dependent probe amplification analysis showed a loss of the copy number of VHL exons in paraganglioma. These results suggest that VHL disease contributes to the development of paraganglioma. A literature review showed no reported common missense variants involved in the progression of paraganglioma. The loss of heterozygosity of VHL can be a tumorigenic mechanism of retroperitoneal paraganglioma in VHL disease. However, the low rate of paraganglioma compared with pheochromocytoma is not explained by their genetic background alone.

Combined left thoracoscopic and median sternotomy approach to resect aortopulmonary mediastinal paraganglioma following feeding artery embolization: a case report

Background

Aortopulmonary mediastinal paragangliomas are rare. Complete resection of the tumor is desirable regardless of tumor size in view of the risk of sudden death induced by adjacent organ compression and poor prognosis after partial resection or untreated observation. Due to the hypervascularity of the tumor, the risk of intraoperative bleeding is significant, and cardiopulmonary bypass is often required for complete resection.

Case presentation

The patient was diagnosed as having bilateral carotid body tumors and supposedly an aortic body tumor at the age of 43 and eventually underwent resections of bilateral carotid body tumors at the age of 52. The pathology of the carotid body tumors was compatible with paraganglioma on both sides. A familial succinate dehydrogenase subunit D mutation was subsequently identified. Five years later, a contrast-enhanced computed tomography scan showed an enlarged tumor of 45 mm in size in the aortopulmonary mediastinum. Based on the previously known genetic mutation, the tumor was thought to be a paraganglioma. After confirming with an endocrinologist that the aortic body tumor was non-functional, radiologists performed preoperative embolization of the feeding vessels. Subsequently, a surgical team consisting of thoracic and cardiovascular surgeons resected the aortic body tumor using a video-assisted small left thoracotomy approach combined with a median sternotomy approach. The procedure was completed without cardiopulmonary bypass or blood transfusion. The patient was discharged home on postoperative day 9 uneventfully.

Conclusions

After conduction of preceding interventional embolization of multiple feeding vessels, we employed a video-assisted thoracoscopic surgical approach to dissect the aspects of the tumor adjacent to the esophagus, descending thoracic aorta, and left pulmonary artery, followed by a median sternotomy approach to dissect the other aspects of the tumor adjacent to the ascending aorta, aortic arch, right pulmonary artery, and trachea. There have been no reports on scheduled preoperative embolization of feeding vessels to an aortopulmonary mediastinal paraganglioma. Multidisciplinary approach was effective for complete resection of this challenging rare mediastinal tumor.

Incidence and risk factors for myocardial injury after laparoscopic adrenalectomy for pheochromocytoma: A retrospective cohort study

Background

Pheochromocytoma is a rare catecholamine-secreting tumor. Tumor resection remains a high-risk procedure due to intraoperative hemodynamic instability nowadays, which may lead to myocardial injury. We aimed to determine the incidence and associated risk factors for myocardial injury after laparoscopic adrenalectomy for pheochromocytoma.

Methods

Adult patients (n=350, American Society of Anesthesiology physical status 1–3) who underwent elective laparoscopic adrenalectomy for pheochromocytoma under general anesthesia between January 31, 2013 and January 31, 2020 were included in this observational, retrospective, single-center, cohort study. Blood troponin I levels were measured before and during the first 2 days after surgery. Myocardial injury was defined as an elevated troponin I level exceeding the 99th percentile upper reference limit due to cardiac ischemic causes.

Results

Myocardial injury occurred in 42/350 patients (12.0%, 95% confidence interval: 9.0%–15.9%). In multivariable analysis (adjusted odds ratios [95% confidence intervals]), previous ischemic heart disease or stroke (5.04 [1.40–18.08]; P=0.013), intraoperative heart rate >115 bpm (2.55 [1.06–6.12]; P=0.036), intraoperative systolic blood pressure >210 mmHg (2.38 [1.00–5.66]; P=0.049), and perioperative decrease in hemoglobin level(1.74 [1.15–2.64] per g/dL decrease; P=0.008) were associated with an increased risk of myocardial injury. For the cumulative duration of dichotomized intraoperative hemodynamics, multivariable analysis showed that intraoperative heart rate >115 bpm for >1 minute (2.67 [1.08–6.60]; P=0.034) and systolic blood pressure >210 mmHg for >1 minute (3.78 [1.47–9.73]; P=0.006) were associated with an increased risk of myocardial injury. The risk of myocardial injury progressively increased with a longer cumulative duration of intraoperative tachycardia and hypertension.

Conclusions

There is a high incidence of myocardial injury after laparoscopic adrenalectomy for pheochromocytoma. The identified risk factors may assist physicians in detecting high-risk patients and providing guidance for intraoperative hemodynamics and perioperative hemoglobin management.

Middle mediastinal paraganglioma enclosing the left anterior descending artery: A case report

RATIONALE

Paragangliomas are extremely rare neuroendocrine tumors arising from ganglia. These tumors are barely found in the middle mediastinum.

PATIENT CONCERNS

A 31-year-old male patient was admitted to our hospital for treatment of an middle mediastinal tumor which was found incidentally on echocardiography during a medical checkup. Contrast-enhanced chest computed tomography (CT) demonstrated a well-defined hypervascularized heterogeneous mass located in the middle mediastinum. The tumor showed strong 18F-fluorodeoxyglucose (FDG) activity on positron emission tomography-computed tomography (PET-CT).

DIAGNOSIS

Before the surgery, we presumed the mass was an angiogenic or neurogenic tumor. As a result, the histological features favored a diagnosis of paraganglioma.

INTERVENTIONS

The tumor was completely removed by anterior thoracotomy, along with the proximal segment of the left anterior descending artery (LAD), and coronary artery bypass grafting (CABG) was performed immediately after the tumor excision.

OUTCOMES

The patient had an uneventful recovery. The patient did well in the postoperative follow-up without any complications and signs of recurrence at 3 months, 1 year, 2 year and 4 year.

LESSONS

This report can increase the confidence in surgeries of mediastinal paragangliomas adhering tightly the adjacent structures.

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

Background

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

Case summary

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

Conclusion

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

Spontaneous Retroperitoneal Bleeding as a Complication of Unusual Renal Paraganglioma

Spontaneous retroperitoneal bleeding is a rare occurrence that might have catastrophic implications. We present a 58-year-old male with a 4-day history of progressively worsening left-sided flank pain due to retroperitoneal hemorrhage from a nonfunctional renal paraganglioma. Abdominal contrast CT scan was helpful in locating the tumor, estimating tumor size and extent of bleeding, visualizing the interaction between the tumor and the surroundings, and ruling out any potential metastasis; however, it lacked specificity in identifying the origin of the mass, needing histologic investigation for a conclusive diagnosis. MRI was not available at our center. We report a rare case of spontaneous retroperitoneal bleeding as a complication of an unusual nonfunctional renal paraganglioma, which was initially misdiagnosed as renal cell carcinoma but later confirmed by postoperative histopathology.

Benign phaeochromocytoma presenting with recurrent spells and negative biochemical screening

A woman in her 40s presented with spells of hypertension, warmth, flushing and bradycardia for more than 1 year. Despite normal plasma metanephrines of 0.48 nmol/L (reference range: <0.50 nmol/L) and normal 24-hour urine metanephrines of 199 µg/day (reference range: 52-341 µg/day), an abdominal CT scan was obtained which revealed a 1.7 × 1.4 cm right adrenal gland nodule. During her next spell, 24-hour urine metanephrines were elevated at 585 µg/day with total metanephrines of 1026 µg/day (reference range: 140-785 µg/day). Subsequent MRI demonstrated a 1.5 × 1.5 cm right adrenal gland lesion concerning for phaeochromocytoma. Right adrenal gland excision was performed and pathology confirmed a benign phaeochromocytoma. Follow-up genetic testing was negative. This case highlights the challenges of identifying phaeochromocytomas in the clinical setting. Early imaging may assist in the timely diagnosis and treatment of these tumours in patients presenting with recurrent spells and negative biochemical screening.

Novel Germline PHD2 Variant in a Metastatic Pheochromocytoma and Chronic Myeloid Leukemia, but in the Absence of Polycythemia

Background: Pheochromocytoma (Pheo) and paraganglioma (PGL) are rare tumors, mostly resulting from pathogenic variants of predisposing genes, with a genetic contribution that now stands at around 70%. Germline variants account for approximately 40%, while the remaining 30% is attributable to somatic variants. Objective: This study aimed to describe a new PHD2 (EGLN1) variant in a patient affected by metastatic Pheo and chronic myeloid leukemia (CML) without polycythemia and to emphasize the need to adopt a comprehensive next-generation sequencing (NGS) panel. Methods: Genetic analysis was carried out by NGS. This analysis was initially performed using a panel of genes known for tumor predisposition (EGLN1, EPAS1, FH, KIF1Bβ, MAX, NF1, RET, SDHA, SDHAF2, SDHB, SDHC, SDHD, TMEM127, and VHL), followed initially by SNP-CGH array, to exclude the presence of the pathogenic Copy Number Variants (CNVs) and the loss of heterozygosity (LOH) and subsequently by whole exome sequencing (WES) comparative sequence analysis of the DNA extracted from tumor fragments and peripheral blood. Results: We found a novel germline PHD2 (EGLN1) gene variant, c.153G>A, p.W51*, in a patient affected by metastatic Pheo and chronic myeloid leukemia (CML) in the absence of polycythemia. Conclusions: According to the latest guidelines, it is mandatory to perform genetic analysis in all Pheo/PGL cases regardless of phenotype. In patients with metastatic disease and no evidence of polycythemia, we propose testing for PHD2 (EGLN1) gene variants. A possible correlation between PHD2 (EGLN1) pathogenic variants and CML clinical course should be considered.

Paraganglioma-induced inverted takotsubo-like cardiomyopathy leading to cardiogenic shock successfully treated with extracorporeal membrane oxygenation

Paragangliomas are rare neuroendocrine tumors that originate in the chromaffin cells of the adrenal medulla or lymph nodes. Paragangliomas manifest in rare cases as catecholamine crisis, leading to heart failure, intracranial hemorrhage, renal failure, arrhythmias, pulmonary edema, or multisystem failure. Takotsubo cardiomyopathy is also called apical ballooning syndrome or stress cardiomyopathy. Left ventricular dysfunction with apical hyperkinesis and basilar and midventricular akinesis in the absence of coronary artery disease is highly suggestive of a variant of stress cardiomyopathy (inverted takotsubo cardiomyopathy). Herein, we report the case of a 69-year-old man with an unknown retroperitoneal paraganglioma who suffered from cardiogenic shock due to inverted takotsubo cardiomyopathy. He was treated with venoarterial extracorporeal membrane pulmonary oxygenation (ECMO) in combination with an intra-aortic balloon pump. After the restoration of cardiac function, a successful transition to curative retroperitoneal paraganglioma resection was performed. We conclude that ECMO is a valuable option for undiagnosed endocrine emergencies, helping to restore cardiac function and allowing sufficient time for further accurate diagnosis and specific treatment.

A Study of Paraganglioma Cases With Non-European Ancestry

Capable of generating excess catecholamines, untreated extra-adrenal paragangliomas (PGLs) result in severe cardiovascular morbidity and mortality. Increasingly, a hereditary basis can be identified to underlie PGLs, though such data are largely absent in populations of non-European descent. We present two patients with PGL, both exhibiting similar age, sex, and geographic ancestry. Our patients are unrelated, Kinyarwanda-speaking females from the Democratic Republic of the Congo. The first patient presented with lower extremity edema and poorly controlled hypertension and was found to have multifocal PGL in the abdomen and bladder, proven by biopsy and treated with surgical excision. Our second patient presented with palpitations, shortness of breath, headache, and hypertension, was found to have mediastinal PGL, and underwent surgical excision. Genetic testing was negative in both cases. The first patient has not shown recurrence based on active surveillance with imaging and biochemical testing. There is a concern for recurrence in the second patient, eight years after diagnosis, which is currently being investigated. Our second patient lived at a high altitude for most of her life, pointing toward a possible role of hypoxia in the pathogenesis of her tumor development. Our cases raise questions that require active inquiry regarding additional environmental and/or genetic factors that might predispose to PGLs in uncommon anatomic sites and in understudied, vulnerable populations.

Management of Patients with Treatment of Pheochromocytoma: A Critical Appraisal

Simple Summary

Preoperative medical preparation with an alpha blockade has been implemented early 1960s to prevent intraoperative hemodynamic instability and consequently decrease morbi-mortality in patients at a high risk of complications. Indeed, surgery at that time consisted of open adrenalectomies with a high morbidity and mortality rate. Current clinical guidelines are based on these early experiences. However, emerging technologies have permitted a drastic reduction of the morbi-mortality rate in patients treated for pheochromocytoma. However, the clinical guidelines have not evolved at the same rate. The aim of this systematic review is to assess the evolution of the management of pheochromocytomas and to appraise the current clinical guidelines to the current clinical practices.

Abstract

The management of pheochromocytomas has significantly evolved these last 50 years, especially with the emergence of new technologies such as laparoscopic procedures in the 1990s. A preoperative blockade using antihypertensive medications to prevent intraoperative hemodynamic instability and cardiocirculatory events is recommended by current clinical guidelines. However, these guidelines are still based on former experiences and are subject to discussion in the scientific community. The aim of this systematic review was to assess the evolution of the management of pheochromocytomas. Laparoscopic procedure is established as the standard of care in current practices. Preoperative medical preparation should be questioned because it does not significantly improve intraoperative events or the risk of postoperative complications in current clinical practice. Current clinical recommendations should be revised and upgraded to current clinical practices.

A case report of primary colonic paraganglioma with lymph node metastasis

Background

Paraganglioma is a kind of neuroendocrine tumor that originates from paraganglia outside the adrenal gland. Gastrointestinal tract paraganglioma is very rare and only four cases of paraganglioma originating in the colon have been reported.

Case Presentation

We report a case of metastatic paraganglioma originating in the colon, in which the differential diagnosis was established by comprehensively considering clinical information, histology, immunohistochemistry, and findings of fluorescence in situ hybridization and next generation sequencing analyses. The patient has remained well for over 14 months after the treatment.

Conclusion

Since all paraganglioma have metastatic potential, we believe that radical surgical resection and regular follow-up are necessary. Genetic testing may be indicative of metastatic potential and prognosis. Because colonic paraganglioma is very rare, differential diagnosis is very important. Our report provides experience for the diagnosis and study of paraganglioma in rare sites.

Pheochromocytoma with Takotsubo Syndrome and acute heart failure: a case report

BACKGROUND

Pheochromocytoma is a neuroendocrine tumor that can overproduce catecholamines. Heart failure and Takotsubo Syndrome (TTS) caused by excessive catecholamines are uncommon pheochromocytoma complications.

CASE PRESENTATION

A 27-year-old woman was referred to our center for further preoperative assessment and adrenalectomy. She came to the emergency ward with the typical symptoms of acute coronary syndrome and heart failure, including chest stuffiness, dyspnea, epigastric pain, and diaphoresis. The high level of 24-hour urinary vanillylmandelic acid and abdominal computed tomography findings supported the diagnosis of pheochromocytoma. Transthoracic echocardiography showed diffuse hypokinesis of the left ventricular wall with an ejection fraction of 23%. All symptoms and left ventricular function recovered rapidly after left laparoscopic adrenalectomy. Histopathology findings confirmed the diagnosis of pheochromocytoma. Based on the above findings, we eventually diagnosed her with pheochromocytoma-induced TTS.

CONCLUSIONS

This is a rare case of pheochromocytoma without hypertension complicated by TTS and acute heart failure. A diagnosis of pheochromocytoma-induced TTS should be considered for patients presenting with uncommon heart failure, even in patients without hypertension. Standard treatment is the surgical removal of the adrenal mass.

Benign Neurogenic Tumors

Neurogenic tumors arise from cells of the nervous system. These tumors can be found anywhere along the distribution of the sympathetic and parasympathetic nervous system and are categorized based on cell of origin: ganglion cell, paraganglion cell, and nerve sheath cells. Ganglion cell-derived tumors include neuroblastomas, ganglioneuroblastomas, and ganglioneuromas. Paraganglion cell-derived tumors include paragangliomas and pheochromocytomas. Nerve sheath cell-derived tumors include schwannomas (neurilemmomas), neurofibromas, and neurofibromatosis. Most of these are benign; however, they can cause local compressive symptoms. Surgery is the mainstay of treatment, if clinically indicated. Nonetheless, a thorough preoperative workup is essential, especially for catecholamine-secreting tumors.

Systematic review: Incidence of Pheochromocytoma and Paraganglioma over 70 years

Context

Pheochromocytomas and paragangliomas (PPGLs) are known to be rare. However, there is scant literature reporting their epidemiology, particularly whether the diagnosis of PPGL has increased with advances in medical imaging and biochemical and genetic testing.

Objective

The primary objective of this systematic review was to determine the annual incidence of PPGLs and change over time.

Design

A systematic review was performed. Medline, Embase, PubMed, and Web of Science Core Collection databases were searched to identify studies reporting PPGL incidence. Studies were eligible for inclusion from the database’s inception until August 30, 2021.

Results

A total of 6109 manuscripts were identified; 2282 duplicates were excluded, and a further 3815 papers were excluded after abstract and/or full text review. Twelve studies were included in the final review. The incidence of PPGL ranged from 0.04 to 0.95 cases per 100 000 per year. Incidence increased over time, from approximately 0.2/100,000 individuals in studies performed before 2000, to approximately 0.6/100,000 in studies undertaken after 2010. The mode of diagnosis changed over the same time period, with more patients diagnosed from incidental imaging findings, and fewer at autopsy or from symptoms.

Conclusion

The annual incidence of PPGL has increased over time. Much of this increase is likely from incidental identification of tumors on imaging. However, the epidemiology of PPGL remains understudied, in particular, in associations with altitude, ethnicity, and genetics. To improve early detection and management guidelines, these gaps should be addressed.

Hereditary and Sporadic Pheochromocytoma: Comparison of Imaging, Clinical, and Laboratory Features

BACKGROUND. A considerable fraction of pheochromocytomas initially suspected to be sporadic, whether or not symptomatic, are a result of germline mutations. OBJECTIVE. The purpose of this article is to compare imaging features between hereditary and sporadic pheochromocytomas. METHODS. This retrospective study included 71 patients (39 women, 32 men; median age, 48 years) who underwent adrenal pheochromocytoma resection from January 2002 to October 2021 after preoperative CT or MRI. Two radiologists independently reviewed examinations to assess features of the largest resected pheochromocytoma. Interreader agreement was assessed by prevalence-adjusted bias-adjusted kappa coefficients; a third radiologist resolved discrepancies for further analysis. Genetic testing was used to classify pheochromocytomas as hereditary or sporadic and to classify hereditary pheochromocytomas by germline mutation clusters. Symptoms associated with pheochromocytomas and preoperative biochemical laboratory values were recorded. Groups were compared using Kruskal-Wallis, Fisher exact, and chi-square tests, and false-discovery rate-adjusted p values were computed to account for multiple comparisons. RESULTS. Hereditary pheochromocytoma (n = 32), compared with sporadic pheochromocytoma (n = 39), was associated with younger median age (38 vs 52 years, p = .001) and smaller median size (24 vs 40 mm, p < .001). Interreader agreement for CT and MRI features, expressed as kappa, ranged from 0.44 to 1.00. Hereditary and sporadic pheochromocytoma showed no difference in frequency of calcifications, hemorrhage, cystic change/necrosis, or macroscopic fat on CT, or in frequency of hemorrhage, cystic change/necrosis, macroscopic fat, or microscopic fat on MRI (p > .05). When combining CT and MRI, cystic change/necrosis was observed in 35% of hereditary versus 67% of sporadic pheochromocytomas (p = .10). Hereditary pheochromocytoma, compared with sporadic, had lower frequency of symptoms (31% vs 74%; p = .004) and lower 24-hour urinary normetanephrines (1.1 vs 5.1 times upper limits of normal, p = .006). Among hereditary pheochromocytomas, cystic change/necrosis (when assessable on imaging) was present in 18% and 45% of those with cluster 1 (n = 11) and cluster 2 (n = 21) germ-line mutations, respectively. CONCLUSION. Hereditary pheochromocytomas, compared with sporadic, are detected at a younger age and smaller size, produce lower 24-hour urinary normetanephrines, are less often symptomatic, and may less frequently show cystic change/necrosis. CLINICAL IMPACT. Imaging findings may complement clinical and biochemical features in raising suspicion for a previously unsuspected germline mutation in patients with pheochromocytoma.

[Clinical features, diagnosis and treatment for patients presenting with granulation tissue of the external auditory canal]

Objective:To explore the clinical characteristics and diagnosis and treatment in the patients presenting with granulation tissue of the external auditory canal. Methods:The data of 71 postoperative patients presenting with granulation tissue of the external auditory canal in the Department of Otolaryngology, the First Affiliated Hospital of the Air Force Military Medical University from January 2015 to June 2020 were analyzed retrospectively, including the chief complaint, physical examination, auxiliary examination and preoperative imaging, biopsy was performed when necessary to confirm the diagnosis. Among the 71 patients, 30 cases were diagnosed as chronic otitis media, 19 cases were external auditory canal cholesteatoma, 5 cases were external auditory canal carcinoma, 6 cases were paraganglioma, 1 case was granulomatous hemangioma, 1 case was first branchial cleft fistula, 4 cases were granuloma of the external auditory canal, 4 cases were hemangioma of the external auditory canal, and 1 case was foreign body of the external auditory canal. Individualized treatment plans are made according to the characteristics and extent of the lesions. Results:Postoperative follow-up was 12 to 74 months, with an average of （44±18.1） months. Seventy patients（98.6%） had no complications such as sensorineural deafness, external auditory stenosis or peripheral facial paralysis after surgery, and one patient with paraganglioma had postoperative neurological function grade Ⅱ, and was treated with nutritional nerves, and the postoperative neural function recovered to grade Ⅰ after 3 months. Conclusion:The patients presenting with granulation tissue of the external auditory canal can be diagnosed as various diseases. It is necessary to analyze the patient's medical history in detail, confirm the diagnosis in combination with imaging examination, and formulate an individualized treatment plan to reduce misdiagnosis and missed diagnosis.

Preoperative Factors Associated with Intraoperative Maximum Arterial Pressures in Patients with Pheochromocytoma and Paraganglioma

BACKGROUND

Surgery for pheochromocytoma and paraganglioma (PPGL) can lead to life-threatening complications, such as intraoperative hypertensive crises, even when adequate doses of preoperative α-receptor blockades are administered.

OBJECTIVES

The aim of this study was to identify preoperative factors associated with intraoperative maximum arterial pressure (AP) in patients with PPGL.

METHODS

We retrospectively reviewed the cases of 61 PPGL patients who underwent surgical resection in our hospital between 2006 and 2020. The primary outcome was intraoperative maximum AP as a single index for continuous variables. Simple and multiple linear regression model were used for statistical analysis.

RESULTS

The median maximum systolic AP during surgery was 165 mmHg (interquartile range: 150 - 180 mmHg). Log24-h urinary-fractionated metanephrine (MN) and normetanephrine (NMN) was correlated with intraoperative maximum AP (R-squared = 0.218, P < 0.001). Multiple regression analyses showed that diabetes mellitus, one or more of the classic triad, and log24-h urinary-fractionated MN and NMN were independent factors associated with intraoperative maximum AP.

CONCLUSIONS

Patients with PPGL accompanied by diabetes mellitus, one or more of the classic triad, and high log 24-h urinary-fractionated MN and NMN values may be at risk for hypertensive crises during surgery regardless of whether preoperative α-receptor blockades are used. Clinicians should manage these patients more carefully and effectively.