Retroperitoneal Paraganglioma Research Articles

7536 Missed Silent Retroperitoneal Paraganglioma

Abstract Disclosure: S. Lamichhane: None. D.T. Price: None. J.J. Faria-Briceno: None. A. Kaur: None. Introduction: Paragangliomas are rare neuroendocrine tumors comprising about 15-20% of all chromaffin cell tumors and can arise anywhere along the sympathetic and parasympathetic ganglionic chain from skull base to the pelvic floor. About 75% of sympathetic paragangliomas arise in the abdomen out of which majority are functional and secrete catecholamines responsible for the typical clinical features. While the diagnosis is usually made by clinical features and lab elevation of catecholamines, it is estimated that 10-15% of paragangliomas are non-functional and another 10% do not manifest clinically according to the hormone activity, thus posing a significant diagnostic challenge. We report a case of a retroperitoneal paraganglioma diagnosed by biopsy as it was initially missed owing to its silent nature clinically and biochemically. Case report:A 48-year-old smoker with panic disorder, remote history of spontaneous pneumothorax, and exploratory laparotomy for motor vehicle accident visited ER due to left-sided abdominal fullness and weight loss of 10-20 pounds for several months. Review of systems was negative except for mild constipation. He denied taking any medications and BP had been normal. CT abdomen showed a large 13.3 cm mixed cystic and solid mesenteric mass. Core biopsy revealed pheochromocytoma and patient was referred to Endocrinology. Labs showed elevated plasma free metanephrines (MN) 80 pg/ml, normetanephrines (NMN) 190 pg/ml, total MN 270 pg/ml, all less than twice the upper limit of normal and inconclusive, non-elevated 24-hour urine MN and NMN but with inadequate collection, and normal plasma catecholamines. MRI revealed a 13.5 cm mass in the left retroperitoneal sympathetic chain separate from the left adrenal gland and inferior to the left kidney. After pre-op optimization with alpha and beta blocker, patient had an uncomplicated open resection of the mass along with the retroperitoneal lymph nodes (LN). Pathology resulted in 3 benign LNs, a 16.5 cm paraganglioma negative for margin, lymph-vascular invasion, and necrosis. Genetic panel was negative. Follow-up post-surgery at 1 and 3 months with mildly elevated catecholamines and MRI abdomen at 3 months without evidence of recurrent or residual mass and metastasis. PET scan is pending prior authorization. Conclusion: Silent retroperitoneal paragangliomas are exceedingly rare. The diagnosis is often missed when the tumors are asymptomatic, and biomarkers are not elevated. The lack of specific imaging characteristics also adds to the diagnostic challenge. Early recognition can avoid the potential risk of life-threatening hypertensive crisis during surgical intervention. Our case highlights the importance of considering this rare entity in the differential diagnosis of retroperitoneal mass. Presentation: 6/1/2024

Retroperitoneal Functional Paraganglioma: A Case Report and Review of the Literature

Retroperitoneal paragangliomas are rare neuroendocrine tumors. They are defined as extra-adrenal chromaffin tumors and account for around 1/5th of all chromaffin tumors. They are often asymptomatic and can reach significant dimensions. We report the case of a 52-year-old female patient who presented with abdominal pain. Thoraco-abdomino-pelvic computed tomography (TAP CT) showed a right retroperitoneal tumor, urinary methoxylates were elevated. After adequate pharmacological preparation, the patient underwent surgery without complications. Blood pressure and urinary catecholamines were normal after surgery.

P001 AN UNCOMMON CAUSE OF HIGH BLOOD PRESSURE IN YOUNG BASKETBALL PLAYER

Paragangliomas are rare neuroendocrine tumors that affect approximately 1.5–9 patients per million. They originate from chromaffin cells of the adrenal medulla or sympathetic and parasympathetic ganglia. Paragangliomas account for 10%–20% of retroperitoneal tumors and can manifest at any age. These tumors can secrete catecholamines, leading to symptoms such as hypertension, headaches, and diaphoresis.However, palpitations or tachycardia may also be present. Definitive treatment entails surgical resection, with acceptable rates of morbidity and mortality, necessitating careful patient preparation and intraoperative management. Case Presentation: We present the case of a 29-year-old man with a BMI 26,5 kg/m2, who is physically active and without other cardiovascular risk factors, episodic hypertension, headaches and blush. A contrast CT scan of the abdomen revealed a retroperitoneal intercavoaortic mass and 24-hour urine Normetanephrines were significantly elevated, indicating a functional paraganglioma. Laboratory tests revealed an elevated plasma normetanephrine level of 1838 pg/ml (reference values 0 - 180 pg/ml). The patient was prepared for surgery with alpha blockers, followed by beta blockers. Intraoperative blood pressure elevation was managed with intravenous beta blockers. Postoperatively, the patient did not require anti-hypertensives. The tumor, measuring 6x4x3.5 cm, histopathology and immunohistochemistry confirmed the diagnosis of a normetanephrine producing paraganglioma. The genetic study revealed a pathogenic variant in the SDHB gene, specifically the c.166_170delCCTCA (p.Pro56Tyrfs*5) in heterozygosity. This variant is associated with a 49% risk of Pheochromocytoma and Hereditary Paraganglioma, a 14% risk of Renal Carcinoma and susceptibility to Gastrointestinal Stromal Tumors. The c.166_170delCCTCA variant follows an autosomal dominant inheritance pattern, indicating a 50% risk of recurrence. Conclusions: The diagnosis of extra-adrenal retroperitoneal paragangliomas remains challenging due to the silent evolution of the condition. It is essential to consider screening patients who are young, and present with resistant arterial hypertension for secondary hypertension.

The relationship between clinical characteristics and pathological features in patients with pheochromocytomas/paragangliomas

Objective: To explore the correlation between clinical characteristics and pathological features in patients with pheochromocytoma/paraganglioma (PPGLs). Methods: A case series study. A retrospective analysis was conducted on patients with single and primary PPGLs after postoperative pathological diagnosis who were admitted to Peking Union Medical College Hospital between January 2019 and December 2022. The patients were divided into the Ki-67<3% group and the Ki-67≥3% group with Ki-67 proliferation index of 3% as the threshold. The relationship between clinical and pathological characteristics of PPGLs was analyzed. Results: A total of 399 PPGLs patients were included, with 177 males and 222 females, aged [M(Q1, Q3)] 45.0(35.5, 53.0) years. Among them, 226 (56.6%) cases originated from the adrenal gland, while 104 cases (26.1%) from the retroperitoneum. 20.9% (27/129) of the patients were found to harbor germline mutations of susceptibility genes, with SDHB mutations being the most common (10.1%, 13/129). The Ki-67 staining was performed on 302 cases, with a Ki-67 proliferation index [M(Q1, Q3)] of 2.0% (1.0%, 3.0%). There were 194 cases in Ki-67<3% group and 108 cases in Ki-67≥3% group. Compared with the patients in Ki-67<3% group, the age of onset in Ki-67≥3% group was younger (P=0.029). Compared with the patients with paragangliomas without SDHB or Cluster 1A-related gene mutations, positive 131I-meta-iodobenzylguanidine (131I-MIBG) imaging or negative O-6-methylguanine-DNA methyltransferase (MGMT) immunohistochemistry staining, those with SDHB or Cluster 1A-related gene mutations, negative 131I-MIBG imaging or positive MGMT immunohistochemistry staining had a higher Ki-67 index (all P<0.05). Compared with adrenal pheochromocytoma, retroperitoneal paragangliomas had a higher proportion of SDHB mutations and a higher proportion of normetanephrine (NMN) secretory types (all P<0.05). Compared with adrenal pheochromocytoma, the maximum diameter of head and neck paraganglioma tumors was smaller [3.0 (1.9, 3.8) cm vs 4.7 (3.4, 6.4) cm, P<0.001] and the proportion of Ki-67≥3% was higher (61.3% vs 33.8%, P=0.007). Conclusions: PPGLs patients with earlier onset age, SDHB or Cluster 1A-related gene mutations, negative 131I-MIBG imaging, or positive MGMT immunohistochemistry staining tend to have a higher Ki-67 index. Head and neck tumors, though smaller, exhibit a higher proliferation potential.

Analysis of clinical and pathological characteristics of retroperitoneal paraganglioma and associated prognostic factors.

The aim of this study is to explore the long-term prognostic risk factors associated with patients diagnosed with retroperitoneal paraganglioma (RPGL) and examine their clinical and pathological characteristics. Expressions of biomarkers were identified using immunohistochemistry (IHC) and case databases were retrospectively searched. Survival analysis was performed using Kaplan-Meier and Cox risk regression to identify the factors that influence the postoperative progression-free survival of patients with RPGL. A total of 105 patients, most of whom had tumors situated in the paraaortic region, and whose average tumor size was 8.6 cm, were enrolled in this study. The average follow-up duration was 51 months, with a mortality rate of 19% and a recurrence and metastasis rate of 41.9%. Tumors were assessed using the modified Grading system for Adrenal Pheochromocytoma and Paraganglioma (GAPP), and SDHB, S-100, and Ki-67 were stained using IHC in all cases. Out of the total cases examined, negative in SDHB expression were observed in 18.1% of cases, S-100 expression was negative in 36.2% of cases, and endovascular tumor enboluswas present in approximately 25.7% of cases. The results of the univariate analysis indicated that several factors significantly influenced the progression-free survival of patients with PGL as follow: maximum tumor diameter (>5.5 cm), tumor morphological features, tumor grading (modified GAPP score > 6), SDHB negative, S-100 negative, and expression of proliferation index Ki-67 (>3%) (X2 = 4.217-27.420, p < 0.05). The results of the multivariate analysis indicated that negative of S-100 (p = 0.021) and SDHB (p = 0.038), as well as intravascular tumor thrombus (p = 0.047) expression were independent risk factors for progression-free survival in patients. RPGL is characterized by diverse biological features and an elevated susceptibility to both recurrence and metastasis. Both SDHB and S-100 can be employed as traditional IHC indicators to predict the metastatic risk of PGL, whereas the tumor histomorphology-endovascular tumor enbolus assists in determining the metastasis risk of RPGL.

Pulmonary and retroperitoneal paragangliomas in a young woman: about a case report and literature review

Pulmonary and retroperitoneal paragangliomas in a young woman: about a case report and literature review

An apparently non-functional retroperitoneal SDHB-related paraganglioma

An apparently non-functional retroperitoneal SDHB-related paraganglioma

A rare case of extra adrenal retroperitoneal paraganglioma: case report

Extra adrenal retroperitoneal paragangliomas are neuro endocrine neoplasms with extremely rare incidence and a wide plethora of clinical presentations. They originate from the neural crest cells interspersed throughout the body. They can present with vague symptoms of pain abdomen, hypertension, palpitations and in severe cases with renal failure, and shock owing to catecholamine excess. On the other end of the spectrum they can be totally asymptomatic and detected incidentally. The multitude of clinical presentations and lack of specific diagnostic tests hence pose a great difficulty in the pre-operative diagnosis of the disease. We are presenting a case of a 20-year-old female with vague symptoms to highlight the management and clinical diagnosis of extra adrenal retroperitoneal paraganglioma.

CT Imaging Findings of Extra-adrenal Abdominal Paragangliomas: A Case Series

Extra-adrenal paragangliomas are rare neuroendocrine tumours originating from paraganglia outside the adrenal glands. The present case series illustrates the Computed Tomography (CT) imaging features of three instances of extra-adrenal abdominal paragangliomas. The discussed cases include Retroperitoneal paraganglioma with Inferior Vena Cava (IVC) infiltration and associated hepatic, pancreatic, and skeletal metastasis; Inter-aortocaval paraganglioma; and Organ of Zuckerkandl Paraganglioma. The CT imaging features of the lesions and their relation with the adjacent vascular structures are described. The differential diagnosis and histopathological correlations are discussed. These cases underscore the importance of considering paragangliomas in the differential diagnosis of soft-tissue masses in the abdomen and highlight the role of Contrast-enhanced CT (CECT) imaging in their evaluation. Understanding the diverse imaging characteristics of extra-adrenal paragangliomas aids in accurate diagnosis and appropriate management. Further studies are needed to expand the authors knowledge of these rare tumours and optimise their imaging evaluation.

Development and internal validation of a novel predictive model for SDHB mutations in pheochromocytomas and retroperitoneal paragangliomas.

To develop and internally validate a novel predictive model for SDHB mutations in pheochromocytomas and retroperitoneal paragangliomas (PPGLs). Clinical data of patients with PPGLs who presented to Peking Union Medical College Hospital from 2013 to 2022 and underwent genetic testing were retrospectively collected. Variables were screened by backward stepwise and clinical significance and were used to construct multivariable logistic models in 50 newly generated datasets after the multiple imputation. Bootstrapping was used for internal validation. A corresponding nomogram was generated based on the model. Sensitivity analyses were also performed. A total of 556 patients with PPGLs were included, of which 99 had a germline SDHB mutation. The prediction model revealed that younger age of onset [Odds ratio (OR): 0.93, 95% CI: 0.91-0.95], synchronous metastasis (OR: 6.43, 95% CI: 2.62-15.80), multiple lesion (OR: 0.22, 95% CI: 0.09-0.54), retroperitoneal origin (OR: 5.72, 95% CI: 3.13-10.47), negative 131I-meta-iodobenzylguanidine (MIBG) (OR: 0.34, 95% CI: 0.15-0.73), positive octreotide scintigraphy (OR: 3.24, 95% CI: 1.25-8.43), elevated 24h urinary dopamine (DA) (OR: 1.72, 95% CI: 0.93-3.17), NE secretory type (OR: 2.83, 95% CI: 1.22- 6.59), normal secretory function (OR: 3.04, 95% CI: 1.04-8.85) and larger tumor size (OR: 1.09, 95% CI: 0.99-1.20) were predictors of SDHB mutations in PPGLs, and showed good and stable predictive performance with a mean area under the ROC curve (AUC) of 0.865 and coefficient of variation of 2.2%. This study provided a novel and useful tool for predicting SDHB mutations by integrating easily obtained clinical data. It may help clinicians select suitable genetic testing methods and make appropriate clinical decisions for these high-risk patients.

SAT329 Case Series Of Patients With FGFR-1 Related Pheochromocytoma With A Focus On Biochemical And Imaging Signatures

Abstract Disclosure: S. Jhawar: None. J. Del Rivero: None. K. Pacak: None. Introduction: Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare neuroendocrine tumors arising from chromaffin cells of adrenal gland and neural crest, respectively. 40% of cases are associated with germline mutations and 30-40% somatic driver mutations. Here, we present two patients with PCC who were found to have somatic FGFR1 mutation. FGFR signaling is involved in regulation of tissue repair, angiogenesis, and inflammation. Patient 1: A 70-year-old female with a history of resistant hypertension, episodic palpitations and sweating presented with diffuse abdominal pain and chest tightness. She was noted to have a blood pressure of 220/160 mm Hg. CT scan showed a 4.2 x 3.9 cm left adrenal mass, suspicious for malignancy and a &amp;lt;1 cm retroperitoneal mass. Blood work revealed elevated plasma normetanephrine (NM) 3543 pg/mL (normal 0- 145) and metanephrine (MN) 871 pg/mL (normal 0-62). 18F-FDG PET/CT showed a left adrenal mass without abnormal FDG activity. 68Ga-DOTATATE PET/CT was compatible with left PCC (SUVmax 28). 18F-DOPA PET/CT showed left PCC and a small retroperitoneal PGL. Two weeks after initiating phenoxybenzamine, she underwent total left adrenalectomy. Pathology was consistent with PCC. Molecular testing revealed FGFR1 pathogenic somatic mutation (c.1638C&amp;gt;G p.Asn546Lys). Patient 2: A 73-year-old male with known left renal cell carcinoma presented to our institution for management of recurrent right PCC. He was found to have a 3.8 cm right adrenal incidentaloma eight years ago and elevated plasma NM 6.3 nmol/L (normal &amp;lt;0.9), MN 1.5 nmol/L (normal &amp;lt;0.5). He underwent total right adrenalectomy, and the diagnosis of PCC was confirmed on histopathology. Two years later, he developed a 5.1 x 4.7 cm nodular mass in the right adrenal fossa and a &amp;lt;1 cm liver lesion on CT scan. The adrenal lesion showed intense avidity on 68Ga-DOTATATE PET/CT and 18F-DOPA PET/CT and mild avidity on 18FDG-PET/CT. 18F-DOPA PET/CT also showed avidity towards the liver lesion. He was started on doxazosin and underwent laparoscopic right adrenalectomy. Pathology demonstrated PCC. Whole exome sequencing of the tumor showed pathogenic FGFR1 mutation (c.1638C&amp;gt;G, p.Asn546Lys). Discussion: Activating FGFR1 mutations are associated with sporadic PCC. The biochemical phenotype of our patients showed higher levels of NM than MN. The imaging profile revealed that 18F-DOPA PET/CT was more sensitive than 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT as it showed avidity towards other extra-adrenal lesions. Further studies in larger cohorts are needed to enhance understanding of pathogenesis, biochemical and imaging phenotype, which will help tailor the treatment and potential development of novel targeted therapies. Presentation: Saturday, June 17, 2023

Large functional retroperitoneal paraganglioma: A surgical challenge

ABSTRACT Paraganglioma is relatively rare retroperitoneal tumors. If functional retroperitoneal paragangliomas are misdiagnosed, surgical intervention can precipitate intraoperative hypertensive crises which may have serious consequences. We present a case of a 40-year-old female who presented with a large functional right-sided retroperitoneal paraganglioma encasing the inferior vena cava (IVC). The patient underwent paraganglioma excision with IVC resection with right nephrectomy. Such complex multivisceral resections require surgical expertise and are feasible at high-volume centers experienced in performing retroperitoneal surgeries.

Functional Retrocaval paraganglioma: Case Report and Review of Literature

Functional Retrocaval paraganglioma: Case Report and Review of Literature

Differentiation of retroperitoneal paragangliomas and schwannomas based on computed tomography radiomics

The purpose of this study was to differentiate the retroperitoneal paragangliomas and schwannomas using computed tomography (CT) radiomics. This study included 112 patients from two centers who pathologically confirmed retroperitoneal pheochromocytomas and schwannomas and underwent preoperative CT examinations. Radiomics features of the entire primary tumor were extracted from non-contrast enhancement (NC), arterial phase (AP) and venous phase (VP) CT images. The least absolute shrinkage and selection operator method was used to screen out key radiomics signatures. Radiomics, clinical and clinical-radiomics combined models were built to differentiate the retroperitoneal paragangliomas and schwannomas. Model performance and clinical usefulness were evaluated by receiver operating characteristic curve, calibration curve and decision curve. In addition, we compared the diagnostic accuracy of radiomics, clinical and clinical-radiomics combined models with radiologists for pheochromocytomas and schwannomas in the same set of data. Three NC, 4 AP, and 3 VP radiomics features were retained as the final radiomics signatures for differentiating the paragangliomas and schwannomas. The CT characteristics CT attenuation value of NC and the enhancement magnitude at AP and VP were found to be significantly different statistically (P < 0.05). The NC, AP, VP, Radiomics and clinical models had encouraging discriminative performance. The clinical-radiomics combined model that combined radiomics signatures and clinical characteristics showed excellent performance, with an area under curve (AUC) values were 0.984 (95% CI 0.952–1.000) in the training cohort, 0.955 (95% CI 0.864–1.000) in the internal validation cohort and 0.871 (95% CI 0.710–1.000) in the external validation cohort. The accuracy, sensitivity and specificity were 0.984, 0.970 and 1.000 in the training cohort, 0.960, 1.000 and 0.917 in the internal validation cohort and 0.917, 0.923 and 0.818 in the external validation cohort, respectively. Additionally, AP, VP, Radiomics, clinical and clinical-radiomics combined models had a higher diagnostic accuracy for pheochromocytomas and schwannomas than the two radiologists. Our study demonstrated the CT-based radiomics models has promising performance in differentiating the paragangliomas and schwannomas.

Intraoperative Corrected Diagnosis of a Right Renal Para-Hilar Paraganglioma, Taken Preoperatively for a Renal Tumor

Nonfunctional retroperitoneal paragangliomas are rare tumors. They are defined as extra-adrenal chromaffin tumors and represent about 20% of chromaffin tumors. They are often asymptomatic and can grow to large dimensions. We report the observation of a 67-year-old patient admitted to the operating room for right total nephrectomy for right hilar renal tumor and whose intraoperative dissection of the renal pedicle could demonstrate an exorenal mass. Anatomopathological analysis was in favor of a paraganglioma. Malignant forms, more frequent than benign forms, present a locoregional invasion and metastasize late. The management of paragangliomas must be multidisciplinary but only surgical treatment is curative. However, there is no consensus on the usefulness of complementary therapies, which can nevertheless be used as a symptomatic adjunct. Paragangliomas are genetic in 25% of cases. A genetic investigation must be systematically proposed.

Anesthetic management of an emergency cesarean section in a parturient with inoperable paraganglioma: A challenging case report

Paraganglioma is a neuroendocrine tumor characterized by small organs comprising neuroendocrine cells that can produce catecholamines. Because of the nature of such tumors, hemodynamic instability can pose a management challenge. This condition can influence the provision of medical care across different clinical settings. The aim of this case report is to highlight anesthesia management in parturient patients with abdominopelvic paraganglioma, particularly during an emergency cesarean section. At 34 weeks of gestation, the 33-year-old female patient with three pregnancies and two past deliveries had a known case of inoperable large pelvic and lower abdominal retroperitoneal paraganglioma and poor radiotherapy response. The 15.5 × 4.2 × 22 cm tumor encased the aorta, inferior vena cava, and bilateral iliac vessels, compressing the lumbar vertebrae. The patient had an uneventful and successful cesarean delivery with a multidisciplinary team effort. Paragangliomas are rarely reported in a parturient and its optimization course. Despite being interrupted by an emergency cesarean section, which was handled safely and effectively, both mother and fetus had a safe delivery and postoperative recovery without complications.

Mass size is a major predictor of hypertensive attack during surgery in patients with paraganglioma of retroperitoneum.

Surgical manipulation of paraganglioma can induce a massive release of catecholamines leading to hypertensive attack. But it has been not known about risk factors to cause hypertensive attack because paragangliomas of urinary bladder and retroperitoneum are notably rare tumors and have been recorded as case report or series. We investigated the relationship between mass size and hypertensive attack during surgery in patients with paraganglioma. Our retrospective chart review included 32 patients who had a pathological diagnosis of paraganglioma between March 2006 and May 2021, in single center. We analyzed the risk factors such as age, sex, height, weight, blood pressure before surgery, history of hypertension, pre-operative symptoms, mass location, and mass in 24 patients with retroperitoneal paragangliomas including urinary bladder. Hypertensive attack was defined as systolic blood pressure >180 mmHg during excision of the mass from the electric medical chart. The predictive power was assessed by the area under the curve of the receiver operating characteristic curve. There were 19 retroperitoneal, 5 urinary bladder, 2 middle-ear cavity, 2 mediastinal, 2 neck, 1 spinal cord and 1 duodenal paraganglioma. Seven (29.2%) of the 24 patients had preoperative symptoms such as pain, fluctuation of blood pressure, and palpable mass. Hypertensive attack during surgery occurred in 11 patients (45.8%). There was a significant difference in mass size between groups with (n=11) and without (n=13) fluctuation of blood pressure (P=0.007). The area under curve for predicting surgical complications according to mass size was 0.808 (cutoff size 4.25 cm, sensitivity 72.7%, specificity 76.9%, 95% CI: 0.635-0.981). Mass size impacted occurrence of hypertensive attack during surgery in patients with retroperitoneal paraganglioma. Surgeons have to be watchful regarding of intraoperative hypertension during resection of retroperitoneal masses exceeding 4.25 cm, which are suspected as paraganglioma.

A Rare Case of a Retroperitoneal Paraganglioma: A Case Report

Retroperitoneal paraganglioma is a rare neoplasm that develops from chromaffin cells that secrete catecholamines in the sympathetic ganglia. They are frequently functional and may be benign or malignant depending on the presence of metastasis and/or the occurrence of recurrence. Different imaging modalities play a crucial role in detecting these tumors. The typical CT appearance of PG is that of a well limited isodense mass with an intense contrast enhancement. On MRI, the mass presents an isosignal or hyposignal in T1 and hypersignal in T2 with an early and intense enhancement. The final diagnosis is based on histological and immunohistochemical findings and the surgical excision is the mainstay of the treatment. However, these tumors are often difficult to diagnose and treat. We report a case of a 30-year-old female patient who presented with a 3 months history of constipation, revealing on computed tomography (CT) a retroperitoneal mass lateralized on the right with a close connection to the inferior vena cava. Urine normetadrenaline (metanephrine) was elevated at 451 ug/24h. Neck and chest CT scan and scintigraphy with 123-I labeled metaiodobenzylguanidine (MIBG) were negative. Complete resection of the tumor was performed. The histological examination and immunohistochemical analyses concluded the diagnosis of a paraganglioma.

Minimally invasive management for multifocal pelvic retroperitoneal malignant paraganglioma: a neuropelveological approach

BackgroundPheochromocytoma and Paraganglioma (PGL) are rare neuroendocrine tumors, with an estimated incidence of about 0.6 cases per 100.000 person/year. Overall, 3–8% of them are malignant. These tumors are characterized by a classic triad of symptoms (headaches, palpitations, profuse sweating) due to hypersecretion of catecholamines. Despite several advantages of minimally invasive surgery (MIS) for PGL debulking, the surgical approach is not standardized yet. In this scenario, we aimed to report a case of a multiple recurrent PGL with metastatic retroperitoneal localization involving the pelvic sidewall, excised with MIS.Case presentationWe performed complete laparoscopic-assisted neuronavigation (LANN technique) with isolation of the sacral routes and the sciatic nerve to obtain complete exposure of the main anatomic landmarks. Robotic surgery was used to perform neurolysis of sacral plexus, and partial resection of left splanchnic nerves was needed. After the resection of the first mass, extensive neurolysis of all sacral routes, obturator nerve, pudendal nerve till the entrance of the pudendal (Alcock) canal, and sciatic nerve was performed. Finally, the mass was identified after trans gluteal incision and dissection of the maximum gluteal muscle, and a partial resection of the superior gluteal nerve and slicing of the sciatic nerve were needed to obtain a radical excision of the mass. Then neurorrhaphy of the sectioned nerve fibers of the superior gluteal nerve was performed, and nerve protection was obtained using a collagen nerve wrap. After 18 months of follow-up, the patient is free of disease at the MRI imaging and 123I-metaiodobenzylguanidine scintigraphy.ConclusionsMinimally invasive gynecological surgery with neuropelveological approach could be considered as a feasible option in case of multifocal pelvic retroperitoneal malignant paraganglioma of the pelvic side wall.

An incidental finding of retroperitoneal paraganglioma during the coronavirus disease 2019 pandemic: a case report

BackgroundExtra-adrenal paraganglioma of the retroperitoneum is a very rare neoplasm arising from cells of the primitive neural crest. Although paragangliomas are considered benign and are often found incidentally, they have the potential to metastasize.Case presentationWe report the case of a 68-year-old Caucasian woman with an incidental diagnosis of retroperitoneal paraganglioma that was discovered on chest computed tomography performed for high suspicion of coronavirus disease 2019 pneumonia. The patient showed no metastasis and was successfully treated by complete surgical removal of the tumor.ConclusionAs the diagnosis of paragangliomas is often delayed because of absent clinical symptoms, they represent a significant diagnostic challenge. Although surgery may exacerbate coronavirus disease 2019 infection, surgical resection of this tumor is prioritized, given its malignancy potential, and it must be performed as soon as no infection is detected.