MANAGEMENT OF ENDOCRINE DISEASE: Recurrence or new tumors after complete resection of pheochromocytomas and paragangliomas: a systematic review and meta-analysis

Management of Pheochromocytomas and Paragangliomas

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

The role of the adrenalectomy in the management of pheochromocytoma: the experience of a Portuguese referral center

PURPOSE

Pheochromocytoma is a rare neuroendocrine tumor. Despite the low incidence, these tumors are of indisputable importance. This study aimed to analyze the management of pheochromocytoma in a referral center, with an emphasis on the minimally invasive adrenalectomy, which is the preferred therapeutic approach.

METHODS

A retrospective analysis was performed on a cohort of patients diagnosed with pheochromocytoma who underwent adrenalectomy between January 2013 and December 2022. Clinical data including demographics, timelines, symptomatology, comorbidities, biochemical markers, genetic testing, surgical details, and follow-up outcomes, were collected and analyzed.

RESULTS

The cohort included 44 patients, predominantly women (52.27%), with a median age of 53.39 years (range 13-83). Most of patients exhibited paroxysmal symptoms suggesting catecholamine excess. Documented hypertension was the most frequent (86.36%), along with glucose anomalies (40.01%) and anxiety disorder (31.82%). Genetic testing was performed in 36 (81.81%) patients and 14 (38.88%) revealed a positive result, predominantly RET pathogenic variant. Laparoscopic surgery was performed in 34 (79.07%) patients, showing significantly shorter operative time (2.5 h vs. 4.25 h, t-test p < 0,001) and fewer complications (23.53% vs 77.78%, p = 0.008). Postoperative complications occurred in 36.36% of the patients, mostly mild (grade I, 56.25%), with no mortality. SDHB pathogenic variant correlated with both recurrent and metastatic disease (p = 0.006). One-year follow-up reported 9.09% recurrence and 6.82% metastasis.

CONCLUSIONS

Adrenalectomy demonstrated a high safety and effectiveness. This study exhibited a higher rate of genetic testing referral than other studies. Despite past advances, there is still a need for further studies to establish protocols and evaluate new techniques.

Imaging of Pheochromocytomas and Paragangliomas

Pheochromocytomas/paragangliomas are unique in their highly variable molecular landscape driven by genetic alterations, either germline or somatic. These mutations translate into different clusters with distinct tumor locations, biochemical/metabolomic features, tumor cell characteristics (eg, receptors, transporters), and disease course. Such tumor heterogeneity calls for different imaging strategies in order to provide proper diagnosis and follow-up. This also warrants selection of the most appropriate and locally available imaging modalities tailored to an individual patient based on consideration of many relevant factors including age, (anticipated) tumor location(s), size, and multifocality, underlying genotype, biochemical phenotype, chance of metastases, as well as the patient's personal preference and treatment goals. Anatomical imaging using computed tomography and magnetic resonance imaging and functional imaging using positron emission tomography and single photon emission computed tomography are currently a cornerstone in the evaluation of patients with pheochromocytomas/paragangliomas. In modern nuclear medicine practice, a multitude of radionuclides with relevance to diagnostic work-up and treatment planning (theranostics) is available, including radiolabeled metaiodobenzylguanidine, fluorodeoxyglucose, fluorodihydroxyphenylalanine, and somatostatin analogues. This review amalgamates up-to-date imaging guidelines, expert opinions, and recent discoveries. Based on the rich toolbox for anatomical and functional imaging that is currently available, we aim to define a customized approach in patients with (suspected) pheochromocytomas/paragangliomas from a practical clinical perspective. We provide imaging algorithms for different starting points for initial diagnostic work-up and course of the disease, including adrenal incidentaloma, established biochemical diagnosis, postsurgical follow-up, tumor screening in pathogenic variant carriers, staging and restaging of metastatic disease, theranostics, and response monitoring.

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

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

Endocrine causes of hypertension: literature review and practical approach

Hypertension (HTN) affects more than 30% of adults worldwide. It is the most frequent modifiable cardiovascular (CV) risk factor, and is responsible for more than 10 million death every year. Among patients with HTN, we usually distinguish secondary HTN, that is HTN due to an identified cause, and primary HTN, in which no underlying cause has been found. It is estimated that secondary hypertension represents between 5 and 15% of hypertensive patients [1]. Therefore, routine screening of patients for secondary HTN would be too costly and is not recommended. In addition to the presence of signs suggesting a specific secondary cause, screening is based on specific criteria. Identifying secondary HTN can be beneficial for patients in certain situations, because it may lead to specific treatments, and allow better control of blood pressure and sometimes even a cure. Besides, it is now known that secondary HTN are more associated with morbidity and mortality than primary HTN. The main causes of secondary HTN are endocrine and renovascular (mainly due to renal arteries abnormalities). The most frequent endocrine cause is primary aldosteronism, which diagnosis can lead to specific therapies. Pheochromocytoma and Cushing syndrome also are important causes, and can have serious complications. Other causes are less frequent and can be suspected on specific situations. In this article, we will describe the endocrine causes of HTN and discuss their treatments.

Biochemical Assessment of Pheochromocytoma and Paraganglioma

Pheochromocytoma and paraganglioma (PPGL) require prompt consideration and efficient diagnosis and treatment to minimize associated morbidity and mortality. Once considered, appropriate biochemical testing is key to diagnosis. Advances in understanding catecholamine metabolism have clarified why measurements of the O-methylated catecholamine metabolites rather than the catecholamines themselves are important for effective diagnosis. These metabolites, normetanephrine and metanephrine, produced respectively from norepinephrine and epinephrine, can be measured in plasma or urine, with choice according to available methods or presentation of patients. For patients with signs and symptoms of catecholamine excess, either test will invariably establish the diagnosis, whereas the plasma test provides higher sensitivity than urinary metanephrines for patients screened due to an incidentaloma or genetic predisposition, particularly for small tumors or in patients with an asymptomatic presentation. Additional measurements of plasma methoxytyramine can be important for some tumors, such as paragangliomas, and for surveillance of patients at risk of metastatic disease. Avoidance of false-positive test results is best achieved by plasma measurements with appropriate reference intervals and preanalytical precautions, including sampling blood in the fully supine position. Follow-up of positive results, including optimization of preanalytics for repeat tests or whether to proceed directly to anatomic imaging or confirmatory clonidine tests, depends on the test results, which can also suggest likely size, adrenal vs extra-adrenal location, underlying biology, or even metastatic involvement of a suspected tumor. Modern biochemical testing now makes diagnosis of PPGL relatively simple. Integration of artificial intelligence into the process should make it possible to fine-tune these advances.

Which surgical approach is more favorable for pheochromocytoma of different sizes (< 6 cm vs. ≥ 6 cm)? A single retrospective center experience

BACKGROUND

To compare the surgical effects of lateral transperitoneal approach (LTA) and posterior retroperitoneal approach (PRA) for pheochromocytoma of different sizes.

METHODS

Data on patients with pheochromocytoma from 2014 to 2023 were collected from our hospital. According to different surgical approaches and tumor size, all patients were divided into four groups: tumor size < 6 cm for LTA and PRA and tumor size ≥ 6 cm for LTA and PRA. We compared these two surgical methods for pheochromocytoma of different sizes.

RESULTS

A total of 118 patients with pheochromocytoma underwent successful laparoscopic surgery, including PRA group (n = 80) and LTA group (n = 38). In tumor size < 6 cm, the outcomes were no significant difference in LTA and PRA. In tumor size ≥ 6 cm, there was a significant difference in operation time (214.7 ± 18.9 vs. 154.3 ± 8.2, P = 0.007) and intraoperative blood loss (616.4 ± 181.3 vs. 201.4 ± 45.8, P = 0.037) between LTA and PRA.

CONCLUSION

LTA and PRA were performed safely with similar operative outcomes in patients with pheochromocytoma size < 6 cm. While both LTA and PRA were executed with a commendable safety profile and comparable operative results in patients afflicted by pheochromocytomas < 6 cm, the PRA technique distinctly showcased advantages when addressing large-scale pheochromocytomas (≥ 6 cm). Notably, this manifested in reduced operative time, diminished intraoperative blood loss, decreased hospitalization expenses, and a paucity of procedural complications.

Surgical management of recurrent and extra-adrenal pheochromocytomas requiring vascular resection and reconstruction

This case series highlights that extra-adrenal and recurrent pheochromocytomas can require en bloc vascular resection to achieve negative margins. Through this series of cases performed in a multidisciplinary fashion, we aim to highlight the technical aspects of these cases that can add to their complexity. Vascular invasion alone should not preclude an otherwise feasible oncologic resection.

Long-Term Outcomes after Surgery for Pheochromocytoma and Sympathetic Paraganglioma

BACKGROUND

The prognosis of pheochromocytoma and sympathetic paraganglioma (PHEO/sPGL) is difficult to predict at the time of diagnosis and long-term follow-up data are scarce, especially for apparently benign and sporadic variants. The aim of the study was to analyze the long-term outcomes in PHEO/sPGL patients.

METHODS

A monocentric series of 170 patients who underwent surgery for PHEO/sPGL was analyzed.

RESULTS

The study cohort included 91 female and 79 males with a median age of 48 years (range 6-83). The majority of PHEO/sPGL cases were considered apparently benign at the time of diagnosis; evident malignant behavior was found in 5% of cases. The overall 10-year risk of recurrence was 13%, but it rose up to 33% at 30 years. The risk of new tumor recurrence was higher in patients with hereditary tumors, but the risk was still significant in patients with apparently sporadic variants (20-year risk: 38% vs. 6.5%, respectively; p < 0.0001). The risk of metastatic recurrence was higher in patients with locally aggressive tumors at diagnosis, but the risk was present also in apparently benign variants (5-year risk: 100% vs. 1%, respectively; p < 0.0001).

CONCLUSIONS

Lifelong follow-up is required not only for hereditary PHEO/sPGL but also for apparently benign and sporadic tumors at diagnosis because of the risk of long-term recurrent disease.

Unusual Cardiac Manifestations of a Pheochromocytoma in a Girl

We report the case of an 11-year-old girl who complained about severe asthenia, orthostatic dizziness and abdominal pain for 4 weeks. The primary investigation concluded on febrile urinary tract infection treated by antibiotics. Symptom persistence prompted cardiological and endocrinological investigations. A fluctuation in blood pressure, long QT interval, dilation of the aortic root and left ventricular hypertrophy were documented. Elevated levels of urinary catecholamines together with the presence of a right-sided adrenal mass shown via abdominal ultrasound and magnetic resonance imaging were highly suggestive of a pheochromocytoma. This was confirmed by through iodine-123-metaiodobenzylguathdine ([¹²³I]-mIBG) scintigraphy. Genetic analysis allowed for the exclusion of pathogenic mutations in genes implicated in hereditary paragangliomas and pheochromocytomas but showed a rare somatic mutation in exon 3 of the von Hippel-Lindau gene. The patient was treated with a β-blocker and calcium channel antagonist and underwent laparoscopic right-sided adrenalectomy. Cardiac manifestations resolved soon after surgery indicating that they were secondary to the pheochromocytoma. After 5 years of follow-up, the patient remains asymptomatic without any sign of tumor recurrence. The presence of aortic root dilation, a prolonged QT-interval and left ventricular hypertrophy may be early cardiac manifestations of a pheochromocytoma in a child and should prompt this diagnosis to be evoked.

Surgical treatment of adrenal tumors during pregnancy

While most adrenal tumors are identified incidentally and are non-functional, hormone-secreting tumors can cause morbidity and mortality. Hemodynamic lability and hypertension in pregnancy are associated with worse maternal and fetal outcomes. Achieving a diagnosis of hormone excess due to adrenal tumors can be clinically more difficult in the gravid patient due to normal physiologic alterations in hormones and symptoms related to pregnancy. This review focuses on some nuances of the diagnostic work-up, perioperative care, and surgical management of adrenally-mediated cortisol excess, primary aldosteronism, and pheochromocytoma and paraganglioma in the pregnant patient.

Recurrent Disease in Patients With Sporadic Pheochromocytoma and Paraganglioma

CONTEXT

Long-term follow-up has been recommended for patients with pheochromocytoma or paraganglioma (PPGL) due to potential for recurrent disease. However, the need to follow patients with sporadic PPGL has recently become controversial.

OBJECTIVE

To investigate the prevalence of recurrence among patients with sporadic compared with hereditary PPGL and to identify predictors of recurrence for sporadic disease.

METHODS

This multicenter study included retrospective data from 1127 patients with PPGL. In addition to sex and age at primary tumor diagnosis, clinical information included location, size, and catecholamine phenotype of primary tumors, genetic test results, and subsequent development of recurrent and/or metastatic disease. Patients with sporadic PPGL were defined as those with negative genetic test results.

RESULTS

Prevalence of recurrence among patients with sporadic PPGL (14.7%) was lower (P < 0.001) than for patients with pathogenic variants that activate pseudohypoxia pathways (47.5%), but similar to those with variants that activate kinase pathways (14.9%). Among patients with sporadic recurrent PPGL, 29.1% and 17.7% were respectively diagnosed at least 10 and 15 years after first diagnosis. Multivariable regression analysis showed that a noradrenergic/dopaminergic phenotype (HR 2.73; 95% CI, 1.553-4.802; P < 0.001), larger size (HR 1.82; 95% CI, 1.113-2.962; P = 0.017) and extra-adrenal location (HR 1.79; 95% CI, 1.002-3.187; P = 0.049) of primary tumors were independent predictors of recurrence in sporadic PPGL.

CONCLUSION

Patients with sporadic PPGL require long-term follow-up, as supported by the 14.7% prevalence of recurrent disease, including recurrences at more than 10 years after first diagnosis. The nature of follow-up could be individualized according to tumor size, location, and biochemical phenotype.

Clinical presentation and diagnostic evaluation of pheochromocytoma: case series and literature review

BACKGROUND

Pheochromocytoma is a rare tumor frequently overlooked mainly due to the wide range of its clinical presentation, which may vary from entirely untypical signs and symptoms to life-threatening complications.

METHODS

The present study aims to present a case series recently treated in our center, with emphasis placed on patients' specific characteristics, clinical presentation and diagnostic evaluation. Relevant literature and current guidelines are being briefly reviewed to summarize screening for pheochromocytoma and appropriate diagnostic procedures.

RESULTS

While the classic symptoms include headache, palpitations and sweating with permanent or paroxysmal hypertension, a wide range of clinical manifestations may be attributed to pheochromocytoma. The initial screening test is measurement of plasma or 24-hour urine metanephrine levels. Abdominal computerized tomography with intravenous contrast infusion is suggested as the imaging examination of choice, whereas magnetic resonance imaging should be preferred over CT in exceptional cases. 123I-metaiodobenzylguanidine scintigraphy is particularly useful for establishing the diagnosis of pheochromocytoma and should be further applied to detect or exclude possible metastatic lesions.

CONCLUSION

Early diagnosis of pheochromocytoma is of great significance not only because it represents a curable form of secondary hypertension, but also because it is often related to familial syndromes, malignancy or metastatic disease. Physicians need to be familiar with relevant clinical manifestations and diagnostic steps to raise clinical suspiction of pheochromocytoma and establish a timely diagnosis.

Late Local and Distant Recurrence of Apparently Benign Paraganglioma

Paraganglioma-pheochromocytoma (PPGLs) are relatively rare catecholamine-secreting tumors of chromaffin origin. Due to the sympathetic effects of catecholamine excess, their presentation may range from non-specific symptoms to dangerous hypertensive crises. We present the case of a 36-year-old lady with recurrent paraganglioma (PGL) who presented in emergency with hypertensive crisis. She had a history of surgery for left-sided PGL 18 years earlier. Imaging showed local recurrence with pulmonary metastases and blood biochemistry showed raised urinary metanephrines. In view of her poor general condition, we undertook a staged surgical approach for management. She first underwent en-bloc excision of recurrent PGL with left nephrectomy. Nine weeks later, she underwent a pulmonary metastasectomy. This staged surgical approach resulted in the stabilization of blood pressure and normalization of urinary catecholamine. Although most of these tumors are indolent by nature, this case highlights the metastatic potential of apparently benign PGL. This case explores the possibility of a staged surgical approach in a high-risk patient and emphasizes the need for long-term follow-up in these cases.

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.

Clinical and Pathological Tools for Predicting Recurrence and/or Metastasis in Patients with Pheochromocytoma and Paraganglioma

Pheochromocytomas and paragangliomas are endocrine tumors belonging to the family of neural crest cell-derived neoplasms. They have an extremely variable clinical course, characterized by a non-negligible percentage of relapse and/or metastasis after radical surgery. To date, there are no reliable methods to predict the metastatic potential of these neoplasms, despite several clinical, molecular, and histopathological factors that have been extensively studied in the literature as predictors of the recurrence and/or metastasis in these neoplasms with different performances and results. In this review, we aimed to discuss and analyze the most important clinical and histopathological tools for predicting recurrence risk in patients affected by pheochromocytomas or paragangliomas. Thus, we compared the main available predictive models, exploring their applications in stratifying patients’ risks. In conclusion, we underlined the importance of simple and validated tools to better define disease aggressiveness and establish tailored patients’ treatments and follow-ups.

Postoperative Recurrences in Patients Operated for Pheochromocytomas and Paragangliomas: New Data Supporting Lifelong Surveillance

Simple Summary

At least 10% of pheochromocytomas (PHEOs) and paragangliomas (PPGLs) may recur after the initial surgery. The optimal follow-up time for these tumors remains unknown. We present a cohort of recurrent PPGLs in a clinical care setting of a quaternary center. In this paper, we describe recurrence patterns based on tumor location (head and neck paragangliomas, thoracoabdominal paragangliomas, and pheochromocytomas). We report that the overall mean delay of recurrence was 9.7 years and that one-third of the cohort had a recurrence more than 10 years after the initial surgery. Additionally, 17.6% of recurrent PHEOs were smaller than the predicted cutoff for recurrence (5 cm). Finally, more than 50% of recurrent PPGLs harbored a germline mutation in a susceptibility gene. In sum, this paper supports that overall, the safest option remains a lifelong follow-up.

Abstract

At least 10% of pheochromocytomas (PHEOs) and paragangliomas (PGLs) (PPGLs) may recur after the initial surgery. Guidelines recommend annual screening for recurrence in non-metastatic tumors for at least 10 years after the initial surgical resection and lifelong screening in high-risk patients. However, recent data suggest that a shorter follow-up might be appropriate. We performed a retrospective analysis on patients with PPGLs who had local and/or metastatic recurrences between 1995 and 2020 in our center. Data were available for 39 cases of recurrence (69.2% female) including 20 PHEOs (51.3%) and 19 PGLs (48.7%) (13 head and neck (HNPGL) and 6 thoracoabdominal (TAPGL)). The overall average delay of recurrence was 116.6 months (14–584 months) or 9.7 years and the median was 71 months or 5.9 years. One-third of the cohort had a recurrence more than 10 years after the initial surgery (10–48.7 years). The average tumor size at initial diagnosis was 8.2 cm for PHEOs, 2.7 cm for HNPGLs, and 9.6 cm for TAPGLs. Interestingly, 17.6% of PHEOs were under 5 cm at the initial diagnosis. Metastatic recurrence was identified in 75% of PHEOs, 15.4% of HNPGLs, and 66.7% of TAPGLs. Finally, 12/23 (52.2%) patients with recurrence who underwent genetic testing carried a germline mutation. Overall, the safest option remains a lifelong follow-up.

From SGAP-Model to SGAP-Score: A Simplified Predictive Tool for Post-Surgical Recurrence of Pheochromocytoma

A reliable prediction of the recurrence risk of pheochromocytoma after radical surgery would be a key element for the tailoring/personalization of post-surgical follow-up. Recently, our group developed a multivariable continuous model that quantifies this risk based on genetic, histopathological, and clinical data. The aim of the present study was to simplify this tool to a discrete score for easier clinical use. Data from our previous study were retrieved, which encompassed 177 radically operated pheochromocytoma patients; supervised regression and machine-learning techniques were used for score development. After Cox regression, the variables independently associated with recurrence were tumor size, positive genetic testing, age, and PASS. In order to derive a simpler scoring system, continuous variables were dichotomized, using > 50 mm for tumor size, ≤ 35 years for age, and ≥ 3 for PASS as cut-points. A novel prognostic score was created on an 8-point scale by assigning 1 point for tumor size > 50 mm, 3 points for positive genetic testing, 1 point for age ≤ 35 years, and 3 points for PASS ≥ 3; its predictive performance, as assessed using Somers’ D, was equal to 0.577 and was significantly higher than the performance of any of the four dichotomized predictors alone. In conclusion, this simple scoring system may be of value as an easy-to-use tool to stratify recurrence risk and tailor post-surgical follow-up in radically operated pheochromocytoma patients.

Unclear retroperitoneal tumors, an interdisciplinary challenge - A case report and review of the literature

INTRODUCTION AND IMPORTANCE

Unclear retroperitoneal tumors impose major challenges for clinicians. Tumors can originate primarily from retroperitoneal tissue or secondarily invade into the retroperitoneum. While benign lesions also occur, malignant tumors are far more common. Clinical presentation depends on replacement or invasion of other organs and is therefore highly variable. The heterogeneous tumor composition makes a definitive preoperative diagnosis difficult. Surgical resection is the gold standard for treatment but often proves challenging due to frequent involvement of large retroperitoneal vessels.

CASE PRESENTATION

We present the case of a 70-year old woman diagnosed with a large, unclear retroperitoneal tumor. Initial clinical symptoms were increasing dyspnea and dysphagia in our clinic. Gastroenterologic and cardiologic workup was unremarkable. Computed Tomography (CT) revealed a large retroperitoneal mass in the right upper abdomen with severe displacement of the inferior vena cava and renal veins. The patient was scheduled for primary tumor resection. The procedure was challenging due to the vessel involvement and large blood pressure alterations during tumor mobilization. The post-op pathologic workup then revealed the rare finding of a completely resected paraganglioma. The post-surgical course was uneventful. One year after diagnosis, the patient is relapse-free.

CLINICAL DISCUSSION

Among retroperitoneal tumors, paragangliomas and pheochromocytomas are rare tumor entities. Asymptomatic, sporadic disease is hard to identify preoperatively and can cause unexpected complications in the OR. An experienced team is crucial in achieving best short- and long-term outcomes.

CONCLUSION

This case impressively shows the challenges of retroperitoneal tumors and the importance of interdisciplinary work in these cases.

Recurrence-Free Survival Analysis in Locally Advanced Pheochromocytoma: First Appraisal

CONTEXT

The behavior of locally advanced pheochromocytoma (LAP) remains unknown.

OBJECTIVE

We characterized the population with LAP and recurrence-free survival (RFS).

METHODS

This retrospective multicentric study was run within the ENDOCAN-COMETE network and French Group of Endocrine Tumors (GTE) from 2003 to 2018, including patients from 11 French referral centers with LAP as defined by capsular invasion, vascular invasion, adipose tissue invasion, and/or positive locoregional lymph nodes at diagnosis without evidence of distant metastasis. The main outcome measure was recurrence, defined as tumor reappearance, including local site and/or distant metastasis. The primary endpoint was RFS analysis; secondary endpoints were characterization, overall survival (OS), and prognostic factors of recurrence.

RESULTS

Among 950 patients, 90 (9%) exhibited LAP criteria and 55 met inclusion criteria (median age, 53 years; 61% males; 14% with germline mutation; 84% with catecholamine excess). LAP was defined by 31 (56%) capsular invasions, 27 (49%) fat invasions, 6 (11%) positive lymph nodes, and 22 (40%) vascular invasions. After median follow-up of 54 months (range, 6-180), 12 patients (22%) had recurrences and 3 (5%) died of metastatic disease. Median RFS was 115 months (range, 6-168). Recurrences were local in 2 patients, distant in 2, and both local and distant in 8 patients. Median OS of patients was not reached. Size above 6.5 cm (P = 0.019) and Ki-67 > 2% (P = 0.028) were identified as independent significant prognostic factors in multivariate analysis.

CONCLUSION

LAP represents 9% of pheochromocytoma's population and has a metastatic behavior. This study paves the way for future pathological TNM classification.

Malignant prediction in paragangliomas: analysis for clinical risk factors

INTRODUCTION

Paragangliomas are infrequent neuroendocrine tumours whose only criterion for malignancy is presence of metastases; thus, all paragangliomas show malignant potential. Actually, different risk factors have been analyzed to predict metastases but they remain unclear.

PURPOSE

To analyze clinical, histological, and genetic factors to predict the occurrence of metastasis.

PATIENTS AND METHOD

A multicentre retrospective observational analysis was performed between January 1990 and July 2019. Patients diagnosed with paraganglioma were selected. Clinical, histological, and genetic features were analyzed for the prediction of malignancy.

RESULTS

A total of 83 patients diagnosed with paraganglioma were included, of which nine (10.8%) had malignant paraganglioma. Tumour size was greater in malignant tumours than in benign (6 cm vs. 4 cm, respectively; p = 0.027). The most frequent location of malignancy was the thorax-abdomen-pelvis area observed in six cases (p = 0.024). No differences were observed in histological differentiation, age, symptoms, and catecholaminergic production. The most frequent genetic mutation was SDHD followed by SDHB but no differences were observed between benign and malignant tumours. In the univariate analysis for predictive factors for malignancy, location, tumour size, and histological differentiation showed statistical significance (p = 0.025, p = 0.014, and p = 0.046, respectively); however, they were not confirmed as predictive factors for malignancy in the multivariate analysis.

CONCLUSION

In this study, no risk factors for malignancy have been established; therefore, we recommend follow-up of all patients diagnosed with paraganglioma.

Chromogranin A in a Cohort of Pheochromocytomas and Paragangliomas: Usefulness at Diagnosis and as an Early Biomarker of Recurrence

OBJECTIVE

To evaluate the usefulness of chromogranin A (CgA) in the management of patients with pheochromocytomas (PHEOs) and paragangliomas (PGLs).

METHODS

We retrospectively reviewed the charts of 132 patients with confirmed PHEOs/PGLs (PPGLs) followed at our medical center. CgA was measured in 80 patients at diagnosis. The exclusion criteria removed 19 of these patients. Five patients with relapses were also analyzed.

RESULTS

Our cohort of 61 patients included 34 PHEOs, 14 head and neck PGLs, and 13 thoracoabdominal PGLs. CgA levels were elevated in 53 of 61 patients (86.9%) at diagnosis: 33 of 34 (97.1%) PHEOs, 9 of 14 (64.3%) head and neck paragangliomas, and 11 of 13 (84.6%) thoracoabdominal paragangliomas. For 8 of 13 (61.5%) nonfunctional PPGLs (5 head and neck paragangliomas and 3 thoracoabdominal paragangliomas), increased CgA levels showed potential as a tumor marker during follow-up. Of 10 patients with malignant PPGLs, only 1 had normal CgA levels (10.0%). Among 54 patients with PPGLs who underwent genetic testing, elevated CgA levels were positive in 73.7% of patients carrying a germline genetic variant (pathogenic and of unknown significance) versus 91.4% of patients without a known germline variant. We also report 5 PPGL cases with increased CgA levels as the first detectable marker of tumoral recurrence or progression preceding other biochemical markers or imaging.

CONCLUSION

CgA is a sensitive marker for the diagnosis of PHEO (97.1%) and thoracoabdominal paraganglioma (84.6%). CgA may be useful in the follow-up of nonfunctional PGLs and may also play a complementary role in the early detection of recurrence in secreting PPGLs.

High-specific-activity 131iodine-metaiodobenzylguanidine for therapy of unresectable pheochromocytoma and paraganglioma

Pheochromocytomas and paragangliomas (PPG) are rare cancers arising from the adrenal medulla (pheochromocytoma) or autonomic ganglia (paraganglioma). They have highly variable biological behavior. Most PPG express high-affinity norepinephrine transporters, allowing active uptake of the norepinephrine analog, ¹³¹iodine-metaiodobenzylguanidine (¹³¹I-MIBG). Low-specific-activity forms of ¹³¹I-MIBG have been used since 1983 for therapy of PPG. High-specific-activity ¹³¹I-MIBG therapy improves hypertension management, induces partial radiological response or stable disease, decreases biochemical markers of disease activity and is well tolerated by patients. This drug, approved in the USA in July 2018, is the first approved agent for patients with unresectable, locally advanced or metastatic PPG and imaging evidence of metaiodobenzylguanidine uptake, who require systemic anticancer therapy.

Recurrence Rate of Sporadic Pheochromocytomas After Curative Adrenalectomy: A Systematic Review and Meta-analysis

BACKGROUND

Evidence on follow-up duration for patients with sporadic pheochromocytomas is absent, and current guidelines of the European Society of Endocrinology, American Association of Clinical Endocrinologists and Endocrine Surgeons, and the Endocrine Society are ambiguous about the appropriate duration of follow-up. The aim of this systematic review and meta-analysis is to evaluate the recurrence rate of sporadic pheochromocytomas after curative adrenalectomy.

MATERIALS AND METHODS

A literature search in PubMed, Embase, and the Cochrane Library was performed. A study was eligible if it included a clear report on the number of sporadic patients, recurrence rate, and follow-up duration. Studies with an inclusion period before 1990, <2 years of follow-up, <10 patients, and unclear data on the sporadic nature of pheochromocytomas were excluded. A meta-analysis on recurrence was performed provided that the heterogeneity was low (I2 < 25%) or intermediate (I2 26-75%). Hozo's method was used to calculate weighted mean follow-up duration and weighted time to recurrence with combined standard deviations (SDs).

RESULTS

A total of 13 studies, including 430 patients, were included in the synthesis. The meta-analysis results describe a pooled recurrence rate after curative surgery of 3% (95% confidence interval: 2-6%, I2 = 0%), with a weighted mean time to recurrence of 49.4 months (SD = 30.7) and a weighted mean follow-up period of 77.3 months (SD = 32.2).

CONCLUSIONS

This meta-analysis shows a very low recurrence rate of 3%. Prospective studies, including economical and health effects of limited follow-up strategies for patients with truly sporadic pheochromocytomas should be considered.

An update on adult forms of hereditary pheochromocytomas and paragangliomas

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Local-Regional Recurrence of Pheochromocytoma/Paraganglioma: Characteristics, Risk Factors and Outcomes

OBJECTIVE

To study the characteristics, risk factors, and outcomes of local-regional recurrence of pheochromocytoma and paraganglioma (PPGL).

METHODS

Clinical data of 96 PPGL patients with local-regional recurrence and 112 patients without recurrence were retrospectively analyzed.

RESULTS

Recurrent patients exhibited a median recurrence time of 6.0 (4.0, 9.0) years after resection of the primary tumor. SDHB mutation [HR 4.1 (1.7, 9.5), p=0.001), primary tumor size ≥5cm [HR 2.3 (1.1, 4.7), p=0.028], and average Ki-67 count ≥3% in the primary tumor [HR 2.6 (1.4, 4.9), p=0.003] were independent predictors for recurrence of PPGL. Primary tumor sizes ≥5cm [HR 5.1 (1.7, 15.3), p=0.003] and average Ki-67 counts ≥3% of the primary tumor [HR 2.4 (1.1, 5.2), p=0.035] were independent predictors for recurrence of pheochromocytoma, while SDHB mutation [HR 4.6 (1.5, 13.9), p=0.007] was a predictor for paraganglioma recurrence. Among recurrent patients, 47% (45/96) had multiple nodules in recurrent sites, and 58% (56/96) had metastases, with 20% (19/96) being implantation metastases. The risk of metastases (42% vs. 25%, p=0.030) and death (15% vs. 8%, p=0.003) was significantly increased in untreated patients after recurrence compared with treated patients.

CONCLUSION

Long-term follow-up is necessary for all PPGL patients. Risk factors for recurrence of pheochromocytoma and paraganglioma differ, with primary tumor size and average Ki-67 count representing independent predictors for pheochromocytoma patients and SDHB mutations predicting paraganglioma recurrence. Although the treatment of recurrence can be difficult, patients should be treated once recurrence is detected as it decreases the risk of metastases and death.

Influence of secretory phenotype and preoperative preparation on surgical outcome in pheochromocytoma

OBJECTIVES

Surgery of pheochromocytomas (PCs) still carries a high risk of haemodynamic complications during the perioperative period. We aimed to evaluate the influence of their secretory phenotype and preoperative alpha-blocker treatment on surgical outcome.

DESIGN

A retrospective monocentric study at a tertiary medical centre.

PATIENTS

In this study, 80 consecutive patients operated by the same team for a PC between 1988 and 2018.

RESULTS

Diagnosis was based on typical symptoms and signs in 58 patients, genetic testing in 12 and work-up of an adrenal incidentaloma in 9. It was made during surgery in one patient. A genetic predisposition was found in one-third of index cases (21/62). The majority of the patients (73/79) had a secreting PC; more than 2/3 had an adrenergic phenotype and less than 1/3 a noradrenergic phenotype. The rate of perioperative haemodynamic complications was not influenced by the secretory phenotype, but persistent hypertension after surgery, recurrence and malignancy were more frequently observed in patients with a noradrenergic tumour. Preoperative alpha-blocker treatment was given for ≥ 14 days in 29 patients and, although being more symptomatic at diagnosis, these patients had less haemodynamic complications (3/29 vs 12/51 non-treated patients, P = 0.05).

CONCLUSIONS

The occurrence of haemodynamic complications during surgery was not significantly affected by the secretory phenotype in our study, but noradrenergic tumours show a worse post-surgical outcome. Our data also provide additional support in favour of a sufficient preoperative alpha-blockade in patients with pheochromocytoma.

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

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

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

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

Update on Pheochromocytoma and Paraganglioma from the SSO Endocrine and Head and Neck Disease Site Working Group, Part 2 of 2: Perioperative Management and Outcomes of Pheochromocytoma and Paraganglioma

This is the second part of a two-part review on pheochromocytoma and paragangliomas (PPGLs). In this part, perioperative management, including preoperative preparation, intraoperative, and postoperative interventions are reviewed. Current data on outcomes following resection are presented, including outcomes after cortical-sparing adrenalectomy for bilateral adrenal disease. In addition, pathological features of malignancy, surveillance considerations, and the management of advanced disease are also discussed.

Recurrence and Progression of Head and Neck Paragangliomas after Treatment

OBJECTIVE

To characterize the recurrence of head and neck paragangliomas and the factors associated with disease progression after treatment.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary care center.

SUBJECTS AND METHODS

In total, 173 adults with 189 paragangliomas (41.3% carotid body, 29.1% glomus jugulare, 19.0% glomus tympanicum, and 10.6% glomus vagale) treated between 1990 and 2010 were evaluated to determine the incidence and risk of recurrence using Cox proportional hazards.

RESULTS

The mean (SD) follow-up duration was 8.6 (9.1) years. The incidence was 2.92 recurrences per 100 person-years. The rate of recurrence was 8.2% (95% confidence interval [CI], 3.7-12.7) after 4 years and 17.1% (95% CI, 10.2-24.0) after 10 years. Glomus jugulare tumors were more likely to recur (hazard ratio [HR], 3.69; 95% CI, 1.70-8.01; P < .001) while carotid body tumors were less likely (HR, 0.44; 95% CI, 0.21-0.97; P = .041). Radiation had a lower risk of recurrence or progression compared to surgical excision (HR, 0.30; 95% CI, 0.10-.94; P = .040). Recurrence was associated with right-sided paragangliomas (HR, 3.60; 95% CI, 1.63-7.75; P = .001). The median time to recurrence was 18.4 years. Six (3.2%) patients developed metastasis, which was more common with local recurrence (9.5% vs 1.4%, P = .015).

CONCLUSIONS

Recurrence is more common with glomus jugulare tumors and less common with carotid body tumors. Radiation may have a lower risk of recurrence or progression than surgery for some paraganglioma types. Metastasis is rare but more likely with recurrent disease. Surveillance neck imaging is recommended every several years for decades after treatment.

[Pheochromocytomatosis after adrenalectomy: metastasis or cell seeding?]

Pheochromocytomatosis is defined as a multifocal cell dissemination limited to the operatively opened space with no signs of distant metastasis. After primary adrenalectomy due to a pheochromocytoma this is a rare and underrecognized manifestation of a tumor recurrence. Between 2010 and 2019 a total of 5 patients with the presentation of pheochromocytomatosis were treated in this center. Clinical and survival data were compared to 12 patients with a metastasized pheochromocytoma. Patients presenting with pheochromocytomatosis showed a better but not significant overall survival (136.8 vs. 107 months). Furthermore, patients with pheochromocytomatosis presented more often with a noradrenaline secretion type. Tumor recurrence in the pheochromocytomatosis group occurred on average 69.2 months after the initial diagnosis and was therefore much later than in patients with distant metastases from a pheochromocytoma (39 months, p = 0.13). This article outlines this special manifestation of recurrence of a pheochromocytoma based on this patient collective. Besides technical operative aspects there appears to be evidence for tumor-specific factors that promote the development of pheochromocytomatosis. Importantly, it seems that all patients with a pheochromocytoma should receive lifelong aftercare and that patients should be closely monitored during the first 5 years after surgery.

Predictors of recurrence of pheochromocytoma and paraganglioma: a multicenter study in Piedmont, Italy

The available data on the natural history of pheochromocytomas and paragangliomas after radical surgery are heterogeneous and discordant. The aim of our retrospective multicenter study was to find predictors of recurrence in patients with pheochromocytomas and sympathetic paragangliomas submitted to radical surgery in Piedmont (a region in northwest Italy). We collected data from 242 patients diagnosed between 1990 and 2016. Forty-two patients (17.4%) had disease recurrence. Multivariate analysis showed that genetic mutation (HR = 3.62; 95% CI 1.44-9.13; p = 0.006), younger age (HR = 0.97; 95% CI 0.95-0.99; p = 0.031) and larger tumor size (HR = 1.01; 95% CI 1.00-1.02; p = 0.015) were independently associated with a higher recurrence risk of pheochromocytoma and paraganglioma; in pheochromocytomas, genetic mutation (HR = 3.4; 95% CI 1.00-11.48; p = 0.049), younger age (HR = 0.97; 95% CI 0.94-0.99; p = 0.02), higher tumor size (HR = 1.01; 95% CI 1.00-1.03; p = 0.043) and PASS value (HR = 1.16; 95% CI 1.03-1.3; p = 0.011) were associated with recurrence. Moreover, tumor size was the only predictor of metastatic pheochromocytoma and paraganglioma (HR = 4.6; 95% CI 1.4-15.0; p = 0.012); tumor size (HR = 3.93; 95% CI 1.2-16.4; p = 0.026) and PASS value (HR = 1.27; 95% CI 1.06-1.53; p = 0.007) were predictors of metastatic pheochromocytoma. In conclusion, our findings suggest that the recurrence of pheochromocytoma and sympathetic paraganglioma develops more frequently in younger subjects, patients with a family history of chromaffin tissue neoplasms, mutations in susceptibility genes, larger tumors and higher values of PASS. We recommend genetic testing in all patients with PPGL and strict follow-up at least on an annual basis.

Paragangliomas in Carney-Stratakis Syndrome

Carney-Stratakis Syndrome (CSS) comprises of paragangliomas (PGLs) and gastrointestinal stromal tumors (GISTs). Several of its features overlap with Carney Triad (CT) - PGLs, GISTs, and pulmonary chondromas. CSS has autosomal dominant inheritance, incomplete penetrance, and greater relative frequency of PGL over GISTs. The PGLs in CSS are multicentric and GISTs are multifocal in all the patients, suggesting an inherited susceptibility and associating the two manifestations. In this review, we highlight the clinical, pathological, and molecular characteristics of CSS, along with its diagnostic and therapeutic implications.

Malignant Pheochromocytomas/Paragangliomas and Ectopic Hormonal Secretion: A Case Series and Review of the Literature

Malignant pheochromocytomas (PCs) and paragangliomas (PGLs) are rare neuroendocrine neoplasms defined by the presence of distant metastases. There is currently a relatively paucity of data regarding the natural history of PCs/PGLs and the optimal approach to their treatment. We retrospectively analyzed the clinical, biochemical, imaging, genetic and histopathological characteristics of fourteen patients with metastatic PCs/PGLs diagnosed over 15 years, along with their response to treatment. Patients were followed-up for a median of six years (range: 1-14 years). Six patients had synchronous metastases and the remaining developed metastases after a median of four years (range 2-10 years). Genetic analysis of seven patients revealed that three harbored succinate dehydrogenase subunit B/D gene (SDHB/D) mutations. Hormonal hypersecretion occurred in 70% of patients; normetanephrine, either alone or with other concomitant hormones, was the most frequent secretory component. Patients were administered multiple first and subsequent treatments including surgery (n = 12), chemotherapy (n = 7), radionuclide therapy (n = 2) and radiopeptides (n = 5). Seven patients had stable disease, four had progressive disease and three died. Ectopic hormonal secretion is rare and commonly encountered in benign PCs. Ectopic secretion of interleukin-6 in one of our patients, prompted a literature review of ectopic hormonal secretion, particularly from metastatic PCs/PGLs. Only four cases of metastatic PC/PGLs with confirmed ectopic secretion of hormones or peptides have been described so far.

Missed clinical clues in patients with pheochromocytoma/paraganglioma discovered by imaging

CONTEXT

Pheochromocytomas and paragangliomas (PPGLs) are rare but potentially harmful tumors that can vary in their clinical presentation. Tumors may be found due to signs and symptoms, as part of a hereditary syndrome or following an imaging procedure.

OBJECTIVE

To investigate potential differences in clinical presentation between PPGLs discovered by imaging (iPPGLs), symptomatic cases (sPPGLs) and those diagnosed during follow-up because of earlier disease/known hereditary mutations (fPPGL).

DESIGN

Prospective study protocol, which has enrolled patients from 6 European centers with confirmed PPGLs.

SETTING AND PATIENTS

Data were analyzed from 235 patients (37% iPPGLs, 36% sPPGLs, 27% fPPGLs) and compared for tumor volume, biochemical profile, mutation status, presence of metastases and self-reported symptoms.

RESULTS

iPPGL patients were diagnosed at a significantly higher age than fPPGLs (p<0.001), found to have larger tumors (p=0.003) and higher metanephrine and normetanephrine levels at diagnosis (p=0.021). Significantly lower than in sPPGL, there was a relevant number of self-reported symptoms in iPPGL (2.9 vs. 4.3 symptoms, p<0.001). In 16.2% of iPPGL, mutations in susceptibility genes were detected, although this proportion was lower than in fPPGL (60.9%) and sPPGL (21.5%).

CONCLUSIONS

Patients with PPGLs detected by imaging were older, have higher tumor volume and more excessive hormonal secretion in comparison to those found as part of a surveillance program. Presence of typical symptoms indicates that in a relevant proportion of those patients the PPGL diagnosis had been delayed. Précis: Pheochromocytoma/paraganglioma discovered by imaging are often symptomatic and carry a significant proportion of germline mutations in susceptibility genes.

Risk Stratification on Pheochromocytoma and Paraganglioma from Laboratory and Clinical Medicine

Pheochromocytoma (PCC) and sympathetic paraganglioma (PGL) are rare neuroendocrine tumors characterized by catecholamine production in the adrenal medulla and extra-adrenal paraganglia. PCC and PGL (PPGL) with metastasis was termed malignant PPGL. However, the distinction between “benign” and “malignant” PPGLs has been debated. Currently, all PPGLs are believed to have some metastatic potential and are assigned malignant tumors (ICD-O/3) by the WHO Classification of Endocrine Organs (2017, 4th edition). Therefore, the previous categories benign and malignant PPGL have been eliminated in favor of risk stratification approach. The Grading of Adrenal Pheochromocytoma and Paraganglioma (GAPP) is a tool for risk stratification for predicting metastasis and the prognosis of patients. At least 30% of PPGLs are hereditary, with 20 genes identified and genotype-phenotype correlations clarified. Of these genes, VHL, RET and NF1 have been well investigated and are the primary cause of bilateral PCC. In addition, mutation of succinate dehydrogenase gene subunits SDHB and SDHD are strongly correlated with extra-adrenal location, younger age, multiple tumors, metastasis and poor prognosis. Disease stratification by catecholamine phenotype and molecular profiling correlates with histological grading by GAPP. PPGLs should be understood comprehensively based on clinical, biochemical, molecular and pathological data for patient care. A flow chart for pathological diagnosis is included.

[Delayed recurrence of a phaechromocytoma with metastasis as a cause of severe hypertension in a woman with a surgically intervened retroperitoneal tumour]

We present the case of a woman with a previous history of hypertension and retroperitoneal tumour. The histology was reported as a paraganglioma. There was no clinical follow-up. Years later, there was a recurrence of the phaeochromocytoma after presenting with a difficult to control hypertension, along with elevation of urinary catecholamines. The case aims to highlight the importance of performing a clinical follow-up in these patients, due to the risk of recurrence.

Pheochromocytomas and Hypertension

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

New Perspectives on Pheochromocytoma and Paraganglioma: Toward a Molecular Classification

A molecular biology-based taxonomy has been proposed for pheochromocytoma and paraganglioma (PPGL). Data from the Cancer Genome Atlas revealed clinically relevant prognostic and predictive biomarkers and stratified PPGLs into three main clusters. Each subgroup has a distinct molecular-biochemical-imaging signature. Concurrently, new methods for biochemical analysis, functional imaging, and medical therapies have also become available. The research community now strives to match the cluster biomarkers with the best intervention. The concept of precision medicine has been long awaited and holds great promise for improved care. Here, we review the current and future PPGL classifications, with a focus on hereditary syndromes. We discuss the current strengths and shortcomings of precision medicine and suggest a condensed manual for diagnosis and treatment of both adult and pediatric patients with PPGL. Finally, we consider the future direction of this field, with a particular focus on how advanced molecular characterization of PPGL can improve a patient's outcome, including cures and, ultimately, disease prevention.

Cardiovascular Manifestations of Pheochromocytoma

Pheochromocytomas are rare endocrine tumors that can have a significant impact on a variety of organ systems, including the cardiovascular system. Although the pathophysiology is not completely understood, pheochromocytomas exert their effects through high levels of catecholamines, mainly epinephrine and norepinephrine, which stimulate adrenergic receptors, including those within the cardiovascular system. Although the most common cardiovascular manifestation is hypertension, patients with pheochromocytoma can present with arrhythmia, hypotension, shock, myocardial ischemia, cardiomyopathy, aortic dissection, and peripheral ischemia. The medical management of the cardiovascular effects of pheochromocytoma is via blockade of adrenergic receptors, usually through the use of alpha blockers, with the addition of beta blockers if needed. However, only surgical resection of the pheochromocytoma is potentially curative, and this tumor requires unique management perioperatively. Because of the variability of presentation and the significant morbidity and mortality of patients with an undiagnosed pheochromocytoma, this entity should not be overlooked in the evaluation of patients with a wide variety of cardiovascular disorders.

Update on Modern Management of Pheochromocytoma and Paraganglioma

Despite all technical progress in modern diagnostic methods and treatment modalities of pheochromocytoma/paraganglioma, early consideration of the presence of these tumors remains the pivotal link towards the best possible outcome for patients. A timely diagnosis and proper treatment can prevent the wide variety of potentially catastrophic cardiovascular complications. Modern biochemical testing should include tests that offer the best available diagnostic performance, measurements of metanephrines and 3-methoxytyramine in plasma or urine. To minimize false-positive test results particular attention should be paid to pre-analytical sampling conditions. In addition to anatomical imaging by computed tomography (CT) or magnetic resonance imaging, new promising functional imaging modalities of photon emission tomography/CT using with somatostatin analogues such as ⁶⁸Ga-DOTATATE (⁶⁸Ga-labeled DOTA(0)-Tyr(3)-octreotide) will probably replace ¹²³I-MIBG (iodine-123-metaiodobenzylguanidine) in the near future. As nearly half of all pheochromocytoma patients harbor a mutation in one of the 14 tumor susceptibility genes, genetic testing and counseling should at least be considered in all patients with a proven tumor. Post-surgical annual follow-up of patients by measurements of plasma or urinary metanephrines should last for at least 10 years for timely detection of recurrent or metastatic disease. Patients with a high risk for recurrence or metastatic disease (paraganglioma, young age, multiple or large tumors, genetic background) should be followed up lifelong.

Pheochromocytomatosis associated with a novel TMEM127 mutation

Pheochromocytomatosis, a very rare form of pheochromocytoma recurrence, refers to new, multiple, and often small pheochromocytomas growing in and around the surgical resection bed of a previous adrenalectomy for a solitary pheochromocytoma. We here report a case of pheochromocytomatosis in a 70-year-old female. At age 64 years, she was diagnosed with a 6-cm right pheochromocytoma. She underwent laparoscopic right adrenalectomy, during which the tumor capsule was ruptured. At age 67 years, CT of abdomen did not detect recurrence. At age 69 years, she began experiencing episodes of headache and diaphoresis. At age 70 years, biochemical markers of pheochromocytoma became elevated with normal calcitonin level. CT revealed multiple nodules of various sizes in the right adrenal fossa, some of which were positive on metaiodobenzylguanidine (MIBG) scan. She underwent open resection of pheochromocytomatosis. Histological examination confirmed numerous pheochromocytomas ranging 0.1–1.2 cm in size. Next-generation sequencing of a panel of genes found a novel heterozygous germline c.570delC mutation in TMEM127, one of the genes that, if mutated, confers susceptibility to syndromic pheochromocytoma. Molecular analysis showed that the c.570delC mutation is likely pathogenic. Our case highlights the typical presentation of pheochromocytomatosis, a rare complication of adrenalectomy for pheochromocytoma. Previous cases and ours collectively demonstrate that tumor capsule rupture during adrenalectomy is a risk factor for pheochromocytomatosis. We also report a novel TMEM127 mutation in this case.

Characteristics of Pediatric vs Adult Pheochromocytomas and Paragangliomas

CONTEXT

Pheochromocytomas and paragangliomas (PPGLs) in children are often hereditary and may present with different characteristics compared with adults. Hereditary PPGLs can be separated into cluster 1 and cluster 2 tumors due to mutations impacting hypoxia and kinase receptor signaling pathways, respectively.

OBJECTIVE

To identify differences in presentation of PPGLs between children and adults.

DESIGN

A retrospective cross-sectional clinical study.

SETTING

Seven tertiary medical centers.

PATIENTS

The study included 748 patients with PPGLs, including 95 with a first presentation during childhood. Genetic testing was available in 611 patients. Other data included locations of primary tumors, presence of recurrent or metastatic disease, and plasma concentrations of metanephrines and 3-methoxytyramine.

RESULTS

Children showed higher (P < 0.0001) prevalence than adults of hereditary (80.4% vs 52.6%), extra-adrenal (66.3% vs 35.1%), multifocal (32.6% vs 13.5%), metastatic (49.5% vs 29.1%), and recurrent (29.5% vs 14.2%) PPGLs. Tumors due to cluster 1 mutations were more prevalent among children than adults (76.1% vs 39.3%; P < 0.0001), and this paralleled a higher prevalence of noradrenergic tumors, characterized by relative lack of increased plasma metanephrine, in children than in adults (93.2% vs 57.3%; P < 0.0001).

CONCLUSIONS

The higher prevalence of hereditary, extra-adrenal, multifocal, and metastatic PPGLs in children than adults represents interrelated features that, in part, reflect the lower age of disease presentation of noradrenergic cluster 1 than adrenergic cluster 2 tumors. The differences in disease presentation are important to consider in children at risk for PPGLs due to a known mutation or previous history of tumor.