Surgical therapy of adrenal tumors: guidelines from the German Association of Endocrine Surgeons (CAEK)

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.

[Personalized treatment of pheochromocytoma]

BACKGROUND

Pheochromocytoma is a rare but severe disease of the adrenal glands. The aim of this study is to present and discuss recent developments in the diagnosis and treatment of pheochromocytoma.

MATERIAL AND METHODS

A narrative review article based on the most recent literature is presented.

RESULTS AND DISCUSSION

The proportion of pheochromocytomas as tumors of adrenal origin is about 5% of incidentally discovered adrenal tumors. The classical symptomatic triad of headaches, sweating, and palpitations occurs in only about 20% of patients, while almost all patients show at least 1 of these symptoms. To diagnose pheochromocytoma, levels of free plasma metanephrines or alternatively, fractionated metanephrines in a 24‑h urine collection is required in a first step. In the second step an imaging procedure, computed tomography (CT) or magnetic resonance imaging (MRI), is performed to localize the adrenal tumor. Functional imaging is also recommended to preoperatively detect potential metastases. Genetic testing should always be offered during the course of treatment as 30-40% of pheochromocytomas are associated with genetic mutations. The dogma of preoperative alpha blockade is increasingly being questioned and has been controversially discussed in recent years. Minimally invasive removal of the adrenal tumor is the standard surgical procedure to cure patients with pheochromocytoma. The transabdominal and retroperitoneal laparoscopic approaches are considered equivalent. The choice of the minimally invasive procedure depends on the expertise and experience of the surgeon and should be tailored accordingly. Individualized and regular follow-up care is important after surgery.

Retroperitoneoscopic adrenalectomy may be superior to laparoscopic transperitoneal adrenalectomy in terms of costs and profit: a retrospective pair-matched cohort analysis

BACKGROUND

A direct comparison of the cost-benefit analysis of retroperitoneoscopic adrenalectomy (RPA) versus the minimally invasive transperitoneal access (LTA) approach is currently lacking. We hypothesized that RPA is more cost effective than LTA; promising significant savings for the healthcare system in an era of ever more limited resources.

METHODS

We performed a monocentric retrospective observational cohort study based on data from our Endocrine Surgery Registry. Patients who were operated upon between 2019 and 2022 were included. After pair-matching, both cohorts (RPA vs. LTA) were compared for perioperative variables and treatment costs (process cost calculation), revenue and profit.

RESULTS

Two homogenous cohorts of 43 patients each (RPA vs. LTA) were identified following matching. Patient characteristics between the cohorts were comparable. In terms of both treatment-associated costs and profit, the RPA procedure was superior to LTA (costs: US$5789.99 for RPA vs. US$6617.75 for LTA, P = 0.043; profit: US$1235.59 for RPA vs. US$653.33 for LTA, P = 0.027). The duration of inpatient treatment and comorbidities significantly influenced the cost of treatment and the overall profit.

CONCLUSIONS

RPA appears not only to offer benefits over LTA in terms of perioperative morbidity and length of hospital stay, but also has a superior financial cost/benefit profile.

Pheochromocytoma crisis with refractory Acute Respiratory Distress Syndrome (ARDS), Takotsubo syndrome, emergency adrenalectomy, and need for Extracorporeal Membrane Oxygenation (ECMO) in a previously undiagnosed and asymptomatic patient, due to the use of metoclopramide

BACKGROUND

Pheochromocytoma (PCC) crisis is a rare life-threatening endocrine emergency. The diagnosis and treatment of PCC crisis, with acute respiratory distress syndrome (ARDS) as the first manifestation, is highly challenging, and traditional PCC management strategies are no longer suitable for these patients.

CASE PRESENTATION

A 46-year-old female patient was admitted to the Intensive Care Unit (ICU) following sudden-onset acute respiratory distress and subsequent initiation of mechanical ventilation via endotracheal intubation. She was initially suspected of having a PCC crisis through the bedside critical care ultrasonic examination protocol. The computed tomography examination revealed a left adrenal neoplasm of 6.5cm × 5.9cm. The plasma-free metanephrine level was 100 times higher than the reference value. These findings were compatible with her PCC diagnosis. Alpha-blockers and fluid intake were started immediately. The endotracheal intubation was removed on the 11th day after admission to the ICU. The patient progressed to severe ARDS again, and invasive ventilation and continuous renal replacement therapy were needed. Despite aggressive therapy, her condition deteriorated. Therefore, she underwent veno-arterial extracorporeal membrane oxygenation (VA-ECMO)-assisted emergency adrenalectomy after multidisciplinary discussion. Postoperatively, the patient was supported by VA-ECMO for 7days. She was discharged from the hospital on day 30 after tumor resection.

CONCLUSIONS

This case highlighted the challenges in diagnosing and managing ARDS associated with PCC crisis. The traditional preoperative preparation protocol and optimal operation timing for patients with PCC are not suitable for patients with PCC crisis. Patients with life-threatening PCC crisis may benefit from early tumor removal, and VA-ECMO could maintain hemodynamic stability during and after surgery.

Volume-outcome relationship in adrenal surgery from 2009-2017 in Germany-a retrospective study

OBJECTIVE

Adrenal resections are rare procedures of a heterogeneous nature. While recent European guidelines advocate a minimum annual caseload for adrenalectomies (6 per surgeon), evidence for a volume-outcome relationship for this surgery remains limited.

DESIGN

A retrospective analysis of all adrenal resections in Germany between 2009 and 2017 using hospital billing data was performed. Hospitals were grouped into three tertiles of approximately equal patient volume.

METHODS

Descriptive, univariate, and multivariate analyses were applied to identify a possible volume-outcome relationship (complications, complication management, and mortality).

RESULTS

Around 17 040 primary adrenal resections were included. Benign adrenal tumors (n = 8,213, 48.2%) and adrenal metastases of extra-adrenal malignancies (n = 3582, 21.0%) were the most common diagnoses. Six hundred and thirty-two low-volume hospitals performed an equal number of resections as 23 high-volume hospitals (median surgeries/hospital/year 3 versus 31, P < .001). Complications were less frequent in high-volume hospitals (23.1% in low-volume hospitals versus 17.3% in high-volume hospitals, P < .001). The most common complication was bleeding in 2027 cases (11.9%) with a mortality of 4.6% (94 patients). Overall in-house mortality was 0.7% (n = 126). Age, malignancy, an accompanying resection, complications, and open surgery were associated with in-house mortality. In univariate analysis, surgery in high-volume hospitals was associated with lower mortality (OR: 0.47, P < .001). In a multivariate model, the tendency remained equal (OR: 0.59, P = .104). Regarding failure to rescue (death in case of complications), there was a trend toward lower mortality in high-volume hospitals.

CONCLUSIONS

The annual caseload of adrenal resections varies considerably among German hospitals. Our findings suggest that surgery in high-volume centers is advantageous for patient outcomes although fatal complications are rare.

[Are there still indications for open adrenalectomy?]

Despite the triumph of minimally invasive techniques in adrenal surgery, the indications for open adrenalectomy are indispensable in the canon of treatment options and must remain part of the repertoire of visceral surgery. Open adrenalectomy is indicated for advanced adrenal carcinoma (ENSAT stage III). In addition to the frequent local infiltration of these carcinomas which makes the en bloc resection of adjacent organs necessary, thromboses in the renal vein or the vena cava or multiple lymph node metastases can also necessitate an open procedure; however, open adrenalectomy is justified and must also be discussed for adrenocortical carcinoma ENSAT stages I-II (tumor size ≤ 5 cm or > 5 cm, NO). Furthermore, highly suspicious large adrenal tumors (6-8 cm, Hounsfield units > 20) without preoperative evidence of malignancy and other adrenal pathologies, such as neuroblastomas, large pheochromocytomas and also schwannomas can be an indication for open adrenalectomy.

[Adrenal incidentaloma - differential diagnosis and management]

Adrenal masses are common incidental findings on imaging procedures.In most cases, adrenal incidentalomas are nonfunctioning adrenocortical adenomas, but in up to 20 % they require therapeutic intervention. The aim of this article is to provide essential guidance for clinicians regarding clinical management of patients with adrenal incidentalomas based on the respective current clinical guidelines. The following main questions are addressed: How to distinguish a nonfunctioning incidentaloma from a functioning one and how to assess risk of malignancy? How to define and manage low-level autonomous cortisol secretion, formerly called "subclinical" Cushing's syndrome? Which patients have to be treated surgically and which approach should be used? What follow-up is indicated if the adrenal incidentaloma is not surgically removed?

Impact of Lymphadenectomy on the Oncologic Outcome of Patients with Adrenocortical Carcinoma-A Systematic Review and Meta-Analysis

Simple Summary

The concept of locoregional lymphadenectomy (LND) in adrenocortical cancer (ACC) has gained interest in recent years, but its definite prognostic and therapeutic significance remains to be established. We undertook a systematic review and meta-analysis to determine the oncologic value of LND in ACC, focusing on overall survival as the primary endpoint. Eleven studies were identified and five were included in the meta-analysis, all of them were retrospective studies. Three studies reported the impact of LND on disease-specific survival in patients with stage I–III ACC and revealed a survival benefit of LND, whereas studies including patients with stage I–IV ACC (N = 2) did not show a survival benefit of LND. In summary, our results demonstrate an oncologic benefit of LND in patients undergoing curative-intended surgery for at least localized ACC (stage I–III).

Abstract

(1) Background: Locoregional lymphadenectomy (LND) in adrenocortical carcinoma (ACC) may impact oncological outcome, but the findings from individual studies are conflicting. The aim of this systematic review and meta-analysis was to determine the oncological value of LND in ACC by summarizing the available literature. (2) Methods: A systematic search on studies published until December 2020 was performed according to the PRISMA statement. The primary outcome was the impact of lymphadenectomy on overall survival (OS). Two separate meta-analyses were performed for studies including patients with localized ACC (stage I–III) and those including all tumor stages (I–IV). Secondary endpoints included postoperative mortality and length of hospital stay (LOS). (3) Results: 11 publications were identified for inclusion. All studies were retrospective studies, published between 2001–2020, and 5 were included in the meta-analysis. Three studies (N = 807 patients) reported the impact of LND on disease-specific survival in patients with stage I–III ACC and revealed a survival benefit of LND (hazard ratio (HR) = 0.42, 95% confidence interval (95% CI): 0.26–0.68). Based on results of studies including patients with ACC stage I–IV (2 studies, N = 3934 patients), LND was not associated with a survival benefit (HR = 1.00, 95% CI: 0.70–1.42). None of the included studies showed an association between LND and postoperative mortality or LOS. (4) Conclusion: Locoregional lymphadenectomy seems to offer an oncologic benefit in patients undergoing curative-intended surgery for localized ACC (stage I–III).

The challenge to differentiate between sarcoma or adrenal carcinoma—an observational study

Background

Adrenal sarcomas are rare malignant tumors with structural and clinical similarities to sarcomatoid adrenocortical carcinoma. Preoperative diagnosis of tumors of the adrenal gland can be challenging and often misleading thus detaining patients from appropriate oncological strategies.

Objective

This analysis of a case series evaluated the predictive capability of the primary clinical diagnosis in case of malignancies of the adrenal gland.

Methods

Thirty two patients were treated from 2009 to 2015 at our clinic and analyzed retrospectively. All patients had computed tomography and/or magnet resonance imaging and a primary histopathological examination at our institution after surgery. Ten questionable cases were surveyed by a reference pathologist.

Results

Twelve out of 32 diagnoses had to be revised (37.5%). Only 15 out of 24 tumors primarily classified as adrenocortical carcinoma were finally described as primary adrenal cancer. We found two leiomyosarcomas, one liposarcoma, one sarcomatoid adrenocortical carcinoma, and one epitheloid angiosarcoma among 12 misleading diagnoses. Other tumors turned out to be metastases of lung, hepatocellular, and neuroendocrine tumors. Larger tumors were significantly more often correctly diagnosed compared to smaller tumors. Four patients of the group of revised diagnoses died whereas all patients with confirmed diagnoses survived during the follow-up.

Conclusion

Preoperative assessment of tumors of the adrenal gland is still challenging. In case of wrong primary diagnosis, the prognosis could be impaired due to inadequate surgical procedures or insufficient preoperative oncological treatment.

[Endocrine and neuroendocrine tumors]

Endokrine Tumoren und hier im Speziellen neuroendokrine Neoplasien des Gastrointestinaltraktes (GEP-NETs), Phäochromozytome (PCs), Paragangliome (PGL) und Schilddrüsentumoren sind Paradebeispiele für die Bedeutung von Molekularpathologie und Molekularbiologie für Diagnostik, Klassifikation und letztendlich auch die (chirurgische) Therapie dieser Erkrankungen. Bei GEP-NETs erfolgt das Grading anhand des Ki-67-Index. Dieser bestimmt die Art der molekularen Bildgebung (DOTA [1,4,7,10-Tetraazacyclododecan‑1,4,7,10-tetraessigsäure]/DOPA [3,4-Dihydroxyphenylalanin]/FDG[Fluordesoxyglukose]-PET[Positronenemissionstomographie]/CT [Computertomographie]), die mögliche Therapie (chirurgisch und/oder Radiopeptidtherapie), antiproliferative und symptomkontrollierende Therapie mit Somatostatinanaloga und letztendlich auch die Prognose. PC/PGL können hereditär auftreten (MEN2A [multiple endokrine Neoplasie Typ 2A], VHL [Von-Hippel-Lindau-Tumorsuppressor], NF1 [Neurofibromatose Typ 1], SDH[Succinat-Dehydrogenase]-Mutationen), was die chirurgische Therapie und die präoperative Medikation maßgeblich beeinflusst. Die molekulare Bildgebung hat einen hohen Stellenwert und kann bei grenzwertiger Biochemie wegweisend sein. Auch Nebennierenrindenkarzinome können genetisch determiniert sein. Bei Schilddrüsentumoren ist v. a. die Pathologie der C‑Zelle (C-Zell-Hyperplasie, medulläres Schilddrüsenkarzinom) hervorzuheben. Bei hereditärer Erkrankung (FMTC [familiäres medulläres Schilddrüsenkarzinom], MEN[multiple endokrine Neoplasie]2) ist häufig eine frühe prophylaktische Operation notwendig und verhindert das Auftreten von fortgeschrittenen Karzinomen. Aber auch die Bestimmung des Resektionsausmaßes bei follikulären Läsionen bzw. die Unterscheidung zwischen „non-invasive follicular thyroid neoplasm with papillary-like nuclear features“ (NIFTPs) und follikulären Varianten des papillären Schilddrüsenkarzinoms kann mithilfe spezifischer Marker erfolgen. Insgesamt hat die Molekularpathologie eine zunehmende Bedeutung bei diesen Entitäten und ist auch Inhalt laufender Forschungsprojekte.

Management of adrenocortical carcinoma: are we making progress?

Adrenocortical carcinoma (ACC) is a rare malignancy characterized by aggressive biology and potential endocrine activity. Surgery can offer cure for localized disease but more than half of patients relapse and primary unresectable or metastasized disease is frequent. Prognosis of metastatic ACC is still limited, with less than 15% of patients alive at 5 years. Recent advances in understanding the molecular profile of ACC underline the high complexity of this disease, which is characterized by limited drugable molecular targets as well as by a complex interplay between a yet scarcely understood microenvironment and potential endocrine activity. Particularly steroid-excess further complicates therapeutic concepts such as immunotherapy, which have markedly improved outcome in other disease entities. To date, mitotane remains the only approved drug for adjuvant and palliative care in ACC. Standard chemotherapy-based protocols with cisplatin, doxorubicin and etoposide offer only marginal improvement in long-term outcome and the number of clinical trials conducted is low due to the rarity of the disease. In the current review, we summarize principles of oncological management for ACC from localized to advanced disease and discuss novel therapeutic strategies, including targeted therapies such as tyrosine kinase inhibitors and antibodies, immunotherapy with a focus on checkpoint inhibitors, individualized treatment concepts based on molecular characterization by next generation sequencing methods, the role of theranostics and evolvement of adjuvant therapy.

[EUROCRINE®: adrenal surgery 2015-2019- surprising initial results]

Hintergrund

Seit 2015 erfolgt in Europa mithilfe des EUROCRINE®-Registers eine systematische Dokumentation endokrin-chirurgischer Operationen. Ziel dieser ersten Auswertung war eine Darstellung der Versorgungsrealität für Nebenniereneingriffe in einem homogenen Versorgungsumfeld, entsprechend des deutschsprachigen Raums – bzw. des Präsenzgebiets der Chirurgischen Arbeitsgemeinschaft Endokrinologie (CAEK) der Deutschen Gesellschaft für Allgemein- und Viszeralchirurgie (DGAV) – einschließlich einer Analyse der Adhärenz zu geltenden Therapieempfehlungen.

Methodik

Es erfolgte eine deskriptive Analyse der präoperativen Diagnostik, der angewandten Operationstechniken sowie der zugrunde liegenden histologischen Entitäten der zwischen den Jahren 2015 und 2019 über EUROCRINE® in Deutschland, Österreich und der Schweiz dokumentierten Nebennierenoperationen.

Ergebnisse

In den insgesamt 21 teilnehmenden Kliniken des deutschsprachigen EUROCRINE®-Gebiets wurden 658 Operationen an Nebennieren durchgeführt. In 90 % erfolgten unilaterale, in 3 % bilaterale Adrenalektomien und in 7 % andere Resektionsverfahren. Die in 41 % der Operationen dokumentierte histologische Hauptdiagnose war das adrenokortikale Adenom. In 15 % lagen maligne Befunde zugrunde (einschließlich 6 % Nebennierenrindenkarzinome (ACC) und 8 % Nebennierenmetastasen). 23 % der Operationen erfolgten bei Phäochromozytomen. Diese wurden zu 82 % minimal-invasiv operiert, Nebennierenrindenkarzinome lediglich zu 28 % und Nebennierenmetastasen zu 66 %.

Schlussfolgerung

Überraschenderweise wurden nach Nebennierenadenomen und Phäochromozytomen an dritthäufigster Stelle Nebennierenmetastasen unterschiedlicher Primärtumoren reseziert. 28 % der ACC waren für minimal-invasive Techniken vorgesehen, wobei 20 % dieser Fälle eine Konversion zur offenen Operation erforderten. Die aktuelle Analyse deckte Diskrepanzen zwischen Versorgungsrealität und Leitlinienempfehlungen auf, aus denen sich zahlreiche Fragestellungen ergeben, welche nun in ein überarbeitetes EUROCRINE®-Modul zur Dokumentation von Nebennierenoperationen einfließen werden.

Surgery for Pheochromocytoma: A Single-Center Review of 60 Cases from South Africa

BACKGROUND

There is a paucity of data on the presentation and surgical management of pheochromocytoma in developing nations, particularly in Africa.

METHODS

This study was a retrospective review, which included all patients managed by the Groote Schuur Hospital/University of Cape Town Endocrine Surgery unit for pheochromocytoma and abdominal paragangliomas, from January 2002 to June 2019.

RESULTS

Sixty patients were included in the study, of which 33% were male and 67% female. The mean age was 47 years (range 14-81). The median tumor size was 6 cm, with 45% larger than 6 cm. 92% were located in the adrenal gland (87% unilateral, 5% bilateral), and 8% were extra-adrenal. The conversion rate for laparoscopic cases was 20%, with 55% of cases overall completed laparoscopically. Eleven patients with tumors > 6 cm were initially attempted laparoscopically, of which 3 were converted to open, without any associated increased morbidity. A major adverse event was recorded for 5 cases (8%), including 1 mortality. Overall morbidity, blood loss, operating time and hospital stay were all significantly reduced in the laparoscopic group. There were 5 patients with malignant disease (8%).

CONCLUSION

This large series, from an established academic endocrine surgery unit in Africa, can serve as a benchmark for units with similar settings and resource limitations, to compare their surgical management and perioperative outcomes.

Plant Natural Compounds in the Treatment of Adrenocortical Tumors

Plant natural products are a plethora of diverse and complex molecules produced by the plant secondary metabolism. Among these, many can reserve beneficial or curative properties when employed to treat human diseases. Even in cancer, they can be successfully used and indeed numerous phytochemicals exert antineoplastic activity. The most common molecules derived from plants and used in the fight against cancer are polyphenols, i.e., quercetin, genistein, resveratrol, curcumin, etc. Despite valuable data especially in preclinical models on such compounds, few of them are currently used in the medical practice. Also, in adrenocortical tumors (ACT), phytochemicals are scarcely or not at all used. This work summarizes the available research on phytochemicals used against ACT and adrenocortical cancer, a very rare disease with poor prognosis and high metastatic potential, and wants to contribute to stimulate preclinical and clinical research to find new therapeutic strategies among the overabundance of biomolecules produced by the plant kingdom.

Survival After Adrenalectomy for Metastatic Hepatocellular Carcinoma: A 25-year Institutional Experience

Background

Extrahepatic manifestation of hepatocellular carcinoma (HCC) is rare and primarily affects lung, lymph nodes and bone. Metastases to the adrenal glands are relatively infrequent. This 25-year institutional experience aimed for an analysis of factors influencing survival in patients undergoing surgery for HCC adrenal metastasis.

Methods

A retrospective analysis of the institutional database of the Clinic for General-, Visceral- and Transplantation Surgery of the University Medical Center Mainz, Germany, was performed. Patients who underwent surgery for HCC adrenal metastases from January 1995 to June 2020 were included. Pre-, peri- and postoperative factors with potential influence on survival were assessed.

Results

In 16 patients (14 males, two females), one bilateral and 15 unilateral adrenalectomies were performed (13 metachronous, three synchronous). Thirteen operations were carried out via laparotomy, and three adrenalectomies were minimally invasive (two laparoscopic, one retroperitoneoscopic). Median overall survival (after HCC diagnosis) was 35 months, range: 5–198. Median post-resection survival (after adrenalectomy) was 15 months, range: 0–75. Overall survival was longer in patients with the primary HCC treatment being liver transplantation (median 66 months) or liver resection (median 51 months), compared to only palliative intended treatment of the primary with chemotherapy (median 35 months) or local ablation (median 23 months).

Conclusions

Surgery is a feasible treatment option for patients with adrenal metastases originating from HCC. In patients who underwent adrenalectomy for HCC adrenal metastasis, overall survival was superior, if primary HCC treatment was potentially curative (liver transplantation or resection).

Primary tumour resection for synchronously metastatic phaeochromocytoma and paraganglioma: A population-based study

CONTEXT

Until recently, there are few effective treatment options for patients with synchronous metastatic phaeochromocytoma (PHEO) and paraganglioma (PGL). Surgical resection may improve the survival outcomes of these patients.

OBJECTIVE

To assess the role of surgical resection of the primary tumour in patients with synchronous metastatic PHEO and PGL.

DESIGN

Retrospective analysis of patients with synchronous metastatic PHEO/PGL using the Surveillance, Epidemiology, and End Results database (1988-2016).

PATIENTS

Patients with synchronous metastatic PHEO/PGL who underwent primary tumour resection.

MEASUREMENTS

Overall survival and Cox regression analyses.

RESULTS

A total of 99 patients with metastatic PHEO and 127 metastatic PGL patients were identified from the SEER database. Compared to metastatic PHEO, metastatic PGL patients had a better overall survival (5-year survival rate: 33.3% vs. 49.0%, p = .001). In metastatic PHEO patients, 53 (53.5%) patients underwent surgery for primary site. Surgically treated patients had an improved survival compared to non-surgery patients (5-year survival rate: 50.9% vs. 29.6%, p = .017). Among metastatic PGL patients, primary tumour resection was performed in 74 (58.3%) patients and had no significant effect on the survival of metastatic PGL. In sub-analyses, surgery only conferred a survival benefit in patients with primary tumours originated from aortic/carotid bodies, rather than other sites or abdominal tumours.

CONCLUSION

Our findings suggest that primary tumour resection is associated with improved survival in patients with synchronous metastatic PHEO and those with PGL diseases located in aortic/carotid bodies. In addition, PHEO and PGL should be treated as two distinct clinical entities.

Perioperative management of pheocromocytoma/ paraganglioma: a comprehensive review

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

Intraoperative imaging for remnant viability assessment in bilateral posterior retroperitoneoscopic partial adrenalectomy in an experimental model

BACKGROUND

A surgical approach preserving functional adrenal tissue allows biochemical cure while avoiding the need for lifelong steroid replacement. The aim of this experimental study was to evaluate the impact of intraoperative imaging during bilateral partial adrenalectomy on remnant perfusion and function.

METHODS

Five pigs underwent bilateral posterior retroperitoneoscopic central adrenal gland division (9 divided glands, 1 undivided). Intraoperative perfusion assessment included computer-assisted quantitative fluorescence imaging, contrast-enhanced CT, confocal laser endomicroscopy (CLE) and local lactate sampling. Specimen analysis after completion adrenalectomy (10 adrenal glands) comprised mitochondrial activity and electron microscopy.

RESULTS

Fluorescence signal intensity evolution over time was significantly lower in the cranial segment of each adrenal gland (mean(s.d.) 0·052(0·057) versus 0·133(0·057) change in intensity per s for cranial versus caudal parts respectively; P = 0·020). Concordantly, intraoperative CT in the portal phase demonstrated significantly lower contrast uptake in cranial segments (P = 0·031). In CLE, fluorescein contrast was observed in all caudal segments, but in only four of nine cranial segments (P = 0·035). Imaging findings favouring caudal perfusion were congruent, with significantly lower local capillary lactate levels caudally (mean(s.d.) 5·66(5·79) versus 11·58(6·53) mmol/l for caudal versus cranial parts respectively; P = 0·008). Electron microscopy showed more necrotic cells cranially (P = 0·031). There was no disparity in mitochondrial activity (respiratory rates, reactive oxygen species and hydrogen peroxide production) between the different segments.

CONCLUSION

In a model of bilateral partial adrenalectomy, three intraoperative imaging modalities consistently discriminated between regular and reduced adrenal remnant perfusion. By avoiding circumferential dissection, mitochondrial function was preserved in each segment of the adrenal glands. Surgical relevance Preservation of adrenal tissue to maintain postoperative function is essential in bilateral and hereditary adrenal pathologies. There is interindividual variation in residual adrenocortical stress capacity, and the minimal functional remnant size is unknown. New intraoperative imaging technologies allow improved remnant size and perfusion assessment. Fluorescence imaging and contrast-enhanced intraoperative CT showed congruent results in evaluation of perfusion. Intraoperative imaging can help to visualize the remnant vascular supply in partial adrenalectomy. Intraoperative assessment of perfusion may foster maximal functional tissue preservation in bilateral adrenal pathologies and procedures.

[Surgery of adrenal diseases]

Incidentally discovered adrenal alterations should be separated into those without any clinical importance and adrenal diseases that have to be surgically or conservatively treated. Before operative treatment, in addition to the possible different functional activity of tumors, a differentiation must be made between sporadically arising singular or multiple adrenal tumors or nodular adrenal hyperplasia, adrenal tumors as part of a familial syndrome and metastases of other primary malignant tumors into the adrenal glands. Benign hormonally active adrenal tumors as well as questionable malignant tumors of the adrenal cortex are resected by minimally invasive techniques. For large malignant tumors infiltrating into surrounding tissues and tumors with proven lymph node metastases, the primarily open approach is indicated. Patients with adrenal diseases should always undergo an interdisciplinary assessment and in cases with clear indications for surgery, sometimes transferred to a center with experience in surgery and postoperative management of these patients.

[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.

[Pheochromocytoma and paraganglioma : Importance of diagnostic imaging]

CLINICAL BACKGROUND

If pheochromocytoma (PC) or paraganglioma (PGL) is diagnosed based on serologic studies, imaging is required to locate the adrenal mass for further management. Besides pathognomonic hormonal findings, PC/PGL can exhibit typical imaging features. However, PC/PGL can also show morphological overlap with other pathologies.

STANDARD RADIOLOGICAL METHODS

The modality of choice for evaluation of PC is CT. In case of extra-adrenal location, MRI is superior to CT. Imaging with PET-CT provides complementary information in the differentiation of PC/PGL and is recommended as the imaging modality of choice for malignant PC/PGL. ⁶⁸Ga-DOTATATE (or ⁶⁸Ga-DOTATOC/ ⁶⁸Ga-DOTANOC) PET-CT has high sensitivity for SDHx-mutated PC/PGL and serves for planning of radioreceptor therapy with somatostatin analogues. In contrast, ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphy is important in assessing the potential efficacy of radioreceptor therapy with MIBG.

METHODICAL DETAILS

The CT protocol for PC evaluation should include non-enhanced, arterial, portal-venous and late phases; the latter for the evaluation of wash-out. Recent studies indicate non-enhanced CT alone may be sufficient to rule out PC. For MRI, in- and opposed-phase sequences should be additionally acquired.

PRACTICAL RECOMMENDATIONS

A relevant proportion of PC is diagnosed incidentally. Therefore, imaging of PC will gain further importance. Recent studies show better response rates of PC/PGL after radioreceptor therapy with somatostatin analogues (¹⁷⁷Lu-DOTATATE) than with MIBG. Therefore, ⁶⁸Ga-DOTATATE PET-CT gains further importance-for diagnostic imaging and therapy planning.