24-hour Urinary Metanephrines Research Articles

Sympathetic activity markers in patients with resistant hypertension with renal dysfunction

Aim. To study the informativeness of sympathetic activity markers and perirenal adipose tissue (PRAT) in assessing renal function decline in patients with resistant hypertension (RH).Material and methods. The study included 63 patients with RH of both sexes aged 40-80 years. The main group included 19 patients with chronic kidney disease (CKD). The control group consisted of 44 patients with RH without CKD. All patients were assessed for uric acid, blood lipid profile, beta-adrenergic reactivity of erythrocyte mem­branes, free metanephrine and normetanephrine in plasma and 24-hour urine. The renal function was assessed by the glomerular filtra­tion rate calculated using the CKD-EPI equation. Twenty-four hour blood pressure monitoring was performed on the brachial artery of one arm at intervals of 15 minutes during the day and 30 minutes at night. Kidney size and PRAT were calculated based on the magnetic reso­nance imaging.Results. In both groups of patients, a significant increase in blood normetanephrine and beta-adrenergic reactivity of erythrocyte mem­branes relative to the reference values was shown. Blood and 24-hour urine metanephrine were within the reference intervals. No differences were found between the sympathetic activity indices in the main and control groups. In the main group patients, the PRAT thickness was greater (p=0,013), and the kidney diameter was smaller (p=0,046) than in the control group patients.Conclusion. CKD in RH patients is not accompanied by additional significant changes in sympathetic regulation, assessed by the blood and 24-hour urine catecholamine levels, the degree of beta-adrenergic receptor desensitization and variability of blood pressure. PRAT increase according to magnetic resonance imaging in patients with RH is associated with a decrease in renal filtration function.

8683 Composite Pheochromocytoma/Paraganglioma-Ganglioneuroma: Biochemical And Radiological Features

Abstract Disclosure: S. Agarwal: None. A.P. Dackiw: None. F. Nwariaku: None. J.E. Mosquera: None. L. Jia: None. M.G. Roden: None. O. Hamidi: Advisory Board Member; Self; Corcept Therapeutics. Introduction: Composite pheochromocytoma/paraganglioma with ganglioneuroma (PHEO-GN or PGL-GN) is a rare tumor consisting of chromaffin cells or ganglia tissue combined with a developmentally related neurogenic tumor. Composite tumors can be present in up to 10% of PHEO and are rare with just over 100 cases reported in published literature. We present a case series of patients with PHEO-GN and PGL-GN seen at our tertiary care center to examine their natural history, clinical, radiological, and biochemical characteristics. Methods: We conducted a retrospective longitudinal follow-up study of consecutive adult patients with histologically-proven PHEO-GN and PGL-GN seen between 2013 and 2023. We collected and summarized data on demographics, laboratory findings, radiological results, and clinical outcomes. Results: The cohort comprised 10 patients (60% women): 8 with PHEO-GN (1 diagnosed on autopsy), 1 with PGL-GN, and 1 with PHEO-ganglioneuroblastoma. The median age at diagnosis was 47 years (interquartile range [IQR], 35-60). Most (80%) tumors were discovered incidentally. The prevalence of a genetic syndrome was 40% and included multiple endocrine neoplasia (MEN) 2A, MEN 4, Neurofibromatosis 1, and hereditary PHEO-PGL syndrome due to succinate dehydrogenase type B gene mutation. Nine patients (90%) had biochemically functional tumors with adrenergic biochemical phenotype in 89% and noradrenergic in 11%. The tumor associated with MEN 4 also had dopamine secretion. The median elevation above the upper normal limit of plasma metanephrine was 7.4 (IQR, 1.6-12), 24-hour urine metanephrine was 7.12 (IQR, 3.7-8.8), plasma normetanephrine was 1.7 (IQR, 1.5-1.9), and 24-hour urine normetanephrine was 2.9 (IQR, 2.4-3.5). The median tumor size at the time of diagnosis was 4.2 cm (IQR, 3.3-5.2). The median pre-contrast HU on CT imaging was 37 HU (IQR, 20-40). The median time to surgical excision from the diagnosis was 2.7 months (IQR, 1.9-4.6). All patients that underwent surgery were alive without recurrence of disease at last follow-up visit with a median follow-up of 14.5 months (IQR, 0.5-18.4). Conclusions We present a series of 10 consecutive patients with composite PHEO-GN and PGL-GN. The prevalence of genetic syndrome (40%) was much higher than previously reported (up to 25% in prior reports). PHEO or PGL component of these tumors is commonly biochemically functional with metanephrine and normetanephrine elevation commonly seen. Metastatic or recurrent disease was not observed in our cohort, suggesting favorable outcomes after surgical resection. Presentation: 6/2/2024

8358 A Diagnostic Challenge: Occult Paraganglioma Misdiagnosed as Pheochromocytoma Leading to Unnecessary Adrenalectomy

Abstract Disclosure: A.R. Kasireddy: None. S. Alshami: None. S. Gummalla: None. C. Balasubramaniapandian: None. J.A. Henske: None. A. Albashaireh: None. Background: Pheochromocytomas and paragangliomas are rare neuroendocrine tumors. Catecholamine-secreting paragangliomas, like pheochromocytomas, can present with hypertension, sweating and episodic headaches. Thoughtful consideration must be given to distinguish between the two and potentially avoid a critical misdiagnosis. Case: A 61-year-old woman with hypertension and diabetes presented for evaluation of glomus jugulare discovered on CT of the head during evaluation of worsening hearing loss and tinnitus. She reported a longstanding history of episodic headaches, palpitations, anxiety spells and excessive sweating with more recent onset of ear fullness. When symptoms first presented, she had a left adrenalectomy 3 years prior. CT abdomen at that time showed 1.8 x 2.2 cm left adrenal nodule with a density of 12.2 HU and early contrast washout. Plasma metanephrines were normal but normetanephrines were elevated at 5.1 nmol/L (nl: less than 0.9 nmol/L). 24-hour urine metanephrines were normal but normetanephrines were elevated to 892mcg/24h (nl: 122-676 mcg/24h). MIBG scan was done and showed increased activity in the left adrenal nodule. Decision was made to proceed with left adrenalectomy. Surgical pathology was benign. Present evaluation after discovery of the glomus tumour with worsening symptoms showed normal plasma metanephrines, elevated plasma normetanephrines at 1529.9 pg/ml (0- 285.2 pg/ml), elevated plasma norepinephrine at 3280 pg/ml (0-874 pg/ml), with normal dopamine and epinephrine levels. CT head showed a 3 x 2.7 x 2.1 cm lytic destructive mass within the petrous temporal bone at the left skull base containing multiple internal calcifications. Given the lab and imaging findings, paraganglioma was diagnosed. Genetic testing revealed SDHB mutation. Neurosurgery consultants determined that the tumour was not amenable to resection. She was treated with radiation therapy, alpha blockade, and close blood pressure monitoring. Discussion: This case highlights the importance of reviewing the degree of hormonal elevations as well as the pattern of elevation to obtain a correct diagnosis. Paragangliomas commonly secrete normetanephrines rather than metanephrines and are often not immediately localized. Understanding the most likely genetic mutations when a paraganglioma is suspected can direct appropriate choice of radionuclide scanning agents. In this case, an earlier diagnostic scan may have prevented unnecessary adrenalectomy and facilitated earlier discovery of the paraganglioma. Presentation: 6/2/2024

8097 A Rare Case of a Renal Cell Carcinoma and Pheochromocytoma Collision Tumor

Abstract Disclosure: R. Daas: None. S. Logan: None. W. Sexton: None. V. Chumbalkar: None. M. McGettigan: None. C. Veloski: None. Background: Collision tumors are neoplasms comprised of two or more distinct tumors. A collision tumor consisting of a renal cell carcinoma and pheochromocytoma is extremely rare with less than five cases reported in the literature. Clinical Case: A 64-year-old male with a history of hypertension and type 2 diabetes presented with hematuria. The patient was on 4 anti-hypertensive medications at the time. He noted increased road rage, anxiety, tremors, and insomnia. A CT abdomen/pelvis revealed an exophytic 8.6 x 7.9 cm left upper pole renal mass and a 7.5 x 6.2 cm left adrenal mass. Contrast-enhanced MRI abdomen showed a left upper/interpolar renal mass with heterogenous peripheral enhancement, restricted diffusion, and areas of central necrosis along with a heterogenous, enhancing left adrenal mass with associated restricted diffusion and areas of cystic necrosis. Both masses had associated areas of hyperintense signal on T1 fat-suppressed MRI suggestive of hemorrhage. Lab work revealed ACTH 26.6 pg/mL (7.2-63.3), cortisol 13 ug/dL (3.7-19.4), aldosterone 23.1 ng/dL (4-31), renin 4 ng/mL/hr (0.5-4), dopamine 136 pmol/L (<240), epinephrine 121 pmol/L (<330), norepinephrine 23,666 pmol/L (1050-4800), plasma normetanephrines 12.3 nmol/L (0-0.89), plasma metanephrines <0.10 nmol/L (0-0.49), 24-hour urine normetanephrines 4,178 mcg (122-676) and 24-hour urine metanephrines 4,233mcg (224-832). The patient was treated with alpha blockade prior to left radical nephrectomy, left adrenalectomy and infrahilar paraaortic lymph node dissection. Despite aggressive preoperative alpha blockade with maximal doses of doxazosin, addition of metyrosine and other anti-hypertensives, he developed acute hypertension with adrenal mass manipulation during the procedure and then hypotension following removal. He was admitted to the ICU for management of hypotension with pressors and fluid resuscitation and did well. Post-operative labs showed plasma normetanephrines 0.98 nmol/L (0.00-0.89) and plasma metanephrines 0.11 nmol/L (0.00-0.49). Pathology revealed clear cell renal cell carcinoma (RCC) of the kidney. The adrenal gland showed 2 tumors; one consistent with pheochromocytoma and another intimately associated with the former consistent with metastatic RCC, morphology diagnostic of a collision tumor. Following surgical resection, the patient was referred for genetic testing, surveillance imaging and lab testing, and treated with pembrolizumab adjuvant therapy for stage IV RCC. Conclusion: Although collision tumors are rare, biochemical testing to rule out a pheochromocytoma must be performed for all indeterminate adrenal masses and presumed adrenal metastases of active malignancies. Presentation: 6/2/2024

7564 Adrenal Pheochromocytoma In A Clinically Inapparent Adrenal Mass

Abstract Disclosure: L. Medina Mora: None. S. Htoo: None. A. Sanchez Ruiz: None. M. Harshan: None. A. Busta: None. Introduction: Pheochromocytomas (PCC) are rare tumors that arise from the adrenal medulla, with an estimated annual incidence of 0.8 per 100,000 person-years. These tumors have been associated with significant morbidity and mortality and are considered among the most life-threatening endocrine diseases, particularly if left undiagnosed. Its symptoms can be related to the tumor's mass effect or catecholamine excess. As a result, they can mimic other conditions, often leading to delayed or incorrect diagnosis. A study conducted on 296 patients with PCC treated from 2005 to 2016 found that 61% were discovered incidentally through cross-sectional imaging (CSI). The widespread use of CSI in recent years has led to the identification of asymptomatic cases that would have otherwise gone undetected. In this case, we present a middle-aged female who was incidentally found to have a PCC. Case Report: A 59-year-old female with a history of hypertension, cerebrovascular accident, pulmonary hypertension, systolic heart failure, mitral valve replacement, and asthma presented to the clinic for evaluation of a right adrenal lesion measuring 4.2 x 3.5 cm found during an emergency room visit during the evaluation of chest pain. She had no known family history of brain or endocrine disorders. Her lab results showed elevated plasma metanephrine and normetanephrine to 578.4 (reference range: 0-88) and 459.9 (reference: 0-244), respectively. Additionally, her 24-hour urine metanephrine was elevated to 984 mcg (normal range: 36-209), and Chromogranin A was 164.3 (reference range: 0-101). The rest of her labs, including cortisol, renin, aldosterone, and DHEA-S were unremarkable. A CT with and without contrast revealed a 3.0 x 3.5 x 5.1 cm solid non-calcified right adrenal mass measuring 39 Hounsfield units (HU). In addition, it measured 53 HU in the venous phase and 61 HU in the 15-minute delayed phase (relative washout of <1%; absolute washout of <7%). The patient was treated with alpha-blockers and underwent a robotic-assisted right adrenalectomy. The pathology was significant for a 5.4 cm well-differentiated PCC. The tumor had extended into but not beyond the adrenal capsule. The postoperative course of the patient was uncomplicated. Discussion: After a PCC is detected, the most effective treatment option is to surgically remove it. This procedure necessitates a combination of alpha and beta-blockade to regulate blood pressure and prevent a hypertensive crisis. Despite the success of surgery, there is still uncertainty about the optimal follow-up after the procedure, which often leads to many patients being lost during the process. Furthermore, even a decade after the initial surgery, there remains a substantial likelihood of illness reoccurrence or metastasis, making the situation even more complex. Therefore, it is crucial to adhere to a lifelong follow-up plan that includes annual biochemical testing. Presentation: 6/2/2024

7576 A Rare and Atypical Presentation of Bladder Paraganglioma in a Patient on Long-Term Left Ventricular Assist Device

Abstract Disclosure: S.D. Leungsuwan: None. S.J. Lee: None. S.D. Lim: None. L. Loh: None. Background: Paragangliomas (PGLs) are rare neuroendocrine tumors arising from chromaffin cells. Capable of producing catecholamines, functional PGLs often cause a myriad of autonomic symptoms and complications, including cardiomyopathy. We report a case of bladder PGL in a patient on Left Ventricular Assist Device (LVAD). Clinical Case: A 64-year-old Chinese Female with a history of non-ischaemic cardiomyopathy on long-term continuous LVAD and Cardiac Resynchronisation Therapy Defibrillator (CRT-D) was admitted for recurrent low LVAD flow <2 Litres per minute and labile mean arterial pressure (MAP) 57-151mmHg. She has been on long-term Nebivolol, Entresto, Hydralazine, and Sildenafil without recent dose adjustment. Workup for acute illnesses was non-contributory. 24-hour urine metanephrine and normetanephrine (NM) were 939nmol/d [normal 400-1500nmol/d] and 33883nmol/d [normal 600-1900nmol/d] respectively. Plasma free metanephrine and NM were 0.37nmol/L [normal <0.33nmol/L] and >10.00nmol/L [normal <0.99nmol/L] accordingly. A review of previous ultrasonography and Computed Tomography (CT) imaging revealed a right adnexal mass indenting the bladder which the patient formerly declined further assessment; adrenal glands were normal. FDG-PET CT was done and showed an isolated focus of increased tracer uptake corresponding with the right pelvic mass. An impression of likely bladder PGL was made. A multidisciplinary team including Cardiology, Anaesthesiology, Interventional Radiology (IR), Urology, Gynaecology, and Endocrinology was convened; the patient was recommended surgical resection of the tumor. Preoperatively, she was started on phenoxybenzamine 10mg BD and advised judicious fluid and salt intake. Nebivolol was continued while hydralazine was stopped. This achieved targets of i) MAP 70-80mmHg, ii) approximately 10mmHg MAP postural fluctuation, iii) sitting and standing heart rates 60-70 beats-per-minute (BPM) and 70-80BPM, and iv) no more than 1 PVC every 5 minutes. Two weeks later, she underwent IR-guided angioembolisation and tumor resection uneventfully. Intraoperatively, the patient had haemodynamic fluctuations requiring dynamic administrations of phentolamine, norepinephrine, epinephrine, vasopressin, glyceryl trinitrate, and sodium nitroprusside. Histopathology was consistent with PGL with intact SDH-A and SDH-B expression. Postoperatively, phenoxybenzamine was discontinued and no recurrent LVAD low flow was noted. Subsequent plans for repeat plasma metanephrines and genetic studies were made. Discussion: This case is the first to report an atypical presentation of PGL with LVAD low flow and labile blood pressure. The significant elevations of urine NM (17.8x upper normal limit) and plasma NM (>10.1x upper normal limit) also underline the concept of fold-elevations and post-test probability of PGL. Presentation: 6/3/2024

5074 Licorice Root Supplement As A Cause Of Hypokalemic Hypertension

Abstract Disclosure: G. Gill: None. S.M. Harman: None. L.A. Robles: None. A 67-year-old female Veteran presented to an emergency room with a one-day history of high blood pressure, chest tightness, and exertional dyspnea. Her blood pressure was 162/90 mm Hg, pulse regular at 71 BPM, and pain level 5/10. She had a history of hypertension, stable on hydrochlorothiazide alone, hyperlipidemia, anxiety, and depression. Physical exam was benign. EKG revealed normal sinus rhythm at 60 BPM, normal axis, a prolonged QT interval of 510 ms, and no ST changes. Lab evaluation showed a low potassium of 2.4 mEq/L, sodium 145 mEq/L. Other lab measurements (CBC, liver function tests and cardiac enzymes) were within laboratory reference ranges. Medications included topiramate for migraine and over-the-counter supplements for constipation, “thyroid health,” and a topical “testosterone booster” prescribed by a non-allopathic practitioner. Her hypokalemia was attributed to hydrochlorothiazide and topiramate and both were discontinued. She was started on nifedipine for blood pressure control and 40 mEq/day of potassium for hypokalemia. Within 2 weeks of discharge, she presented again with elevated blood pressure and a plasma potassium of 4.0 mMol/L. Further history revealed that her constipation supplement consisted of licorice root (glycyrrhiza glabra) extract 900 mg per capsule, of which she took 3 to 4 capsules daily. The patient was advised to discontinue all supplements. Thyroid function tests were within normal limits. Due to a suspicion of hyperaldosteronism, the ED physician requested an abdominal CT scan which showed a 1 cm, -17.5 Hounsfield unit, right adrenal nodule. Also consistent with hyperaldosteronism, plasma renin activity (PRA) was suppressed at 0.07 ng/mL/hr. However, a serum aldosterone level was less than 1 ng/dL. Her 24-hour urinary metanephrines were normal and a 24-hour urine free cortisol was 31.6 mcg/dL. Morning plasma cortisol was 5.1 mcg/dL. A tentative diagnosis of licorice-induced hyperaldosteronism was made and the patient was treated with a taper of spironolactone. After discontinuing spironolactone, blood pressure was 116/70mmHg and serum potassium was 4.5 mMol/L with a PRA of 0.66 ng/mL/hr and serum aldosterone of <5.0 ng/dL. The syndrome of factitious hyperaldosteronism due to licorice consumption has been well described. The mechanism, inhibition of renal (type 2) 11-beta-hydroxysteroid dehydrogenase by glycyrrhizic acid, allowing cortisol to exercise its considerable mineralocorticoid action, is well understood. Most prior reports have been in patients habitually consuming licorice candy, usually imported, since conventional licorice sold in the U.S. is artificially flavored. Our report illustrates the importance of obtaining a history of use of over-the-counter supplements and assessing their ingredients and the fact that presence of an adrenal nodule and a low PRA does not always indicate endogenous hyperaldosteronism. Presentation: 6/2/2024

6997 Atypical Presentation of Hereditary Paraganglioma

Abstract Disclosure: O. Abdulhussein: None. R.R. Correa: None. M.D. Lundholm: None. J. Ferri-Guerra: None. G. Madrigol: None. Introduction: Paraganglioma (PGL) is a rare neuroendocrine, highly vascular tumor arising from sympathetic or parasympathetic ganglia chromaffin cells. Some PGL functional while others biochemically silent. Given the possible lack of classic symptoms or convincing catecholamine elevation. They are closely related to pheochromocytomas.• However, the distinction between pheochromocytoma and paraganglioma is essential because of the implication for associated neoplasm and syndromes; paraganglioma is more metastatic. Case: 32-year-old otherwise healthy female presented to primary care clinic for 1 year of dry cough. She was a non-smoker. She denied voice changes, palpitations, hypertension, palpitations, pallor, headache, or diaphoresis, but had noticed a mass growing in her right neck for a year. On exam her blood pressure 107/73 and there was a mobile, round mass felt at the right mandible. CT neck at the time showed reactive lymphadenopathy. She referred to pulmonology and ENT, spirometry and flexible laryngoscopy were unremarkable. For persistent mass 1year later, an MRI of the neck showed a 2.8x2.3x3.8 cm right carotid mass, likely PGL. Biochemical testing revealed elevations in plasma normetanephrine (NM) (269 pg/mL, 18-101 pg/mL) and 24-hour urinary NM (848 ug/24hr, 88-444 ug/24hr) with mild elevation in 24-hour urinary metanephrine (982 ug/24 hr, 140-785 ug/24 hr) and normal plasma metanephrine. The mass was intensely avid on DOTATATE scan without other lesions. Genetic testing uncovered SDHB mutation. She was started on preoperative alpha-blockade with successful resection. She had pathology confirmation of PGL and was set up for annual SDHB surveillance testing. Discussion: A minority of patients with PCC or PGL present with classical “5 P” catecholamine symptoms: pallor, pain, pressure, perspiration, or palpitations. One main reason is a lack of excess catecholamine secretion; 17 years of retrospective data at our center showed that 61% (N=50/82) of patients with PGL with preoperative catecholamine labs had normal levels. Additionally, mild to moderate increases to 2-3x upper limit of normal may be attributed to stress or medications, which obfuscates the distinction between secretory disease and physiologic elevation.Given the infrequency of catecholamine symptoms or secretion, PGL is frequently discovered incidentally. Indeed, 92% (N=110/119) of our PGL cases were found incidentally on imaging or pathology. Alpha-blockade is the preoperative standard of care, many patients are only diagnosed post-operatively by pathology findings. Further study is needed to determine if pre-operative alpha-blockade is needed in all PGL cases, and if so, how we can better identify these patients before they go to the operating room. For now, a high level of suspicion is needed to make a timely PGL diagnosis and facilitate genetic testing. Presentation: 6/1/2024

7553 Thyroid Paraganglioma: A Complex Tale of the Familiar Thyroid Nodule

Abstract Disclosure: V. Moorthy: None. A. Kondapally: None. L.E. Kimball-Ravari: None. Background: Thyroid paragangliomas are rare and often misdiagnosed on fine-needle aspiration (FNA). Clinical Case & Discussion: A 58-year-old female presented with an asymptomatic “cold” thyroid nodule. Ultrasound demonstrated a 2 cm hypoechoic nodule in the isthmus. FNA yielded a follicular lesion of undetermined significance, and genomic sequencing estimated a 50% risk of malignancy prompting the patient to opt for total thyroidectomy. Histopathology and immunohistochemistry (IHC) confirmed the diagnosis of benign paraganglioma (PGL). SDH-B (succinate dehydrogenase subunit B) was notably absent on IHC. Past medical history is significant for hysterectomy for uterine fibroids and obesity, along with a confirmed family history of Hereditary Leiomyomatosis with Renal Cell Cancer (HLRCC). The patient and several family members tested positive for a pathogenic variant of fumarate hydratase (FH) gene implicated in HLRCC and undergo annual MRIs for cancer surveillance. The loss of SDH-B suggests underlying mutation. Germline SDH mutations occur in 20% of patients with pheochromocytoma and PGLs, predisposing to hereditary syndromes. PGLs are catecholamine-secreting neuroendocrine tumors with carotid body and jugular PGLs accounting for 80% of head and neck PGLs (HNPGLs). Thyroid PGLs originate from the inferior laryngeal paraganglia. They are very rare, often non-secretory, and commonly present as asymptomatic solitary nodules. For these reasons, FNA, while contraindicated, is frequently performed. If FNA is considered, pre-procedural alpha-adrenergic blockade is recommended, although catecholamine secretion triggered by FNA is uncommon. Thyroid PGLs are misdiagnosed on FNA as other thyroid neoplasms. Awareness of the more unique cytopathology of thyroid PGLs and a comprehensive IHC can aid in accurate diagnosis. Interestingly, SDH (complex 2) and FH are closely linked enzymes in the Krebs cycle. Emerging evidence correlates germline FH mutations and hereditary pheochromocytoma-paraganglioma. PGLs are less commonly associated with MEN 2A and 2B, NF type 1, VHL, and Carney-Stratakis syndrome and Carney triad. Therefore, additional testing for SDH, RET, VHL and MAX genes was recommended in this case. Total thyroidectomy or lobectomy with or without elective lymph node dissection remains the treatment of choice. Annual 24-hour urine and plasma metanephrine testing will help screen for potential recurrence. Use of GLP1 agonists for weight loss in this patient warrants further genetic and safety evaluation. Clinical Lesson/Conclusion: Often misdiagnosed on FNA, thyroid paragangliomas are rare, with multiple genetic predispositions. FNA is contraindicated and if considered, must be performed after alpha-blockade. Germline SDH mutations are implicated in PGLs and increasing evidence links FH mutations to hereditary PGLs. Presentation: 6/3/2024

7510 Use Of Tumor Markers And Surgery In The Management Of Medullary Thyroid Cancer During Pregnancy

Abstract Disclosure: M. Garver: None. C. Vaz: None. Introduction: Thyroid cancer is the second most diagnosed cancer during pregnancy, predominantly differentiated thyroid malignancies. [1] MTC during pregnancy is rare and challenging to manage due to its aggressive nature. We describe the successful diagnosis and management of MTC during pregnancy. Clinical Case: A 28 yo woman presented with a rapidly growing neck lump for 2 months with an associated unintentional 10lb weight loss and without compressive symptoms. She had no history of childhood radiation exposure or family history of thyroid cancer. Physical exam revealed a hard L lobe thyroid nodule without palpable lymphadenopathy. The patient was 5 weeks pregnant at the time. A neck US revealed a 4.2x2.7x2.0 cm L solid isoechoic thyroid nodule with punctate echogenic foci and microcalcifications. The nodule was classified as TIRADS 4 and ATA high suspicion. FNA noted Bethesda IV with positive IHC stains for chromogranin and calcitonin. Afirma MTC classifier was positive, confirming diagnosis of MTC. At 7 weeks gestation, calcitonin was markedly elevated at 3508 pg/mL (n <5 pg/mL), CEA 29.5 ng/mL (n <2.5 ng/mL) and calcium 10.3mg/dL (8.6-10.2mg/dL). Plasma normetanephrines were elevated to176 pg/mL (n <148 pg/mL) with normal metanephrines 28 pg/mL (n <57 pg/mL) and normal 24-hour urine metanephrines. CT neck revealed 3.2x2.8cm L thyroid nodule without cervical lymphadenopathy. Due to pregnancy status, additional imaging to assess for metastatic disease was deferred until after delivery. Genetic testing did not identify mutations within the thyroid cancer panel including APC, CHEK2, DICER1, MEN1, PRKAR1A, PTEN, RET, SDHB, SDHD, and TP53. The patient underwent total thyroidectomy with neck dissection at 19 weeks gestation without complication. Two weeks postoperative Calcitonin was 2 pg/mL(n <5 pg/mL) and CEA was undetectable. Conclusions: The effect of pregnancy on MTC is not well studied because of low incidence. Guidelines on the timing of surgery for MTC diagnosed during pregnancy are lacking. While evidence confirms that surgery can be safely postponed until after delivery for low risk differentiated thyroid malignancies, there is no consensus on timing of surgery for MTC. Given the aggressive nature of MTC, along with marked elevation of calcitonin and CEA in this case, surgery was performed in the 2nd trimester with excellent outcome. Data is conflicting on accuracy of calcitonin and CEA during pregnancy, with some reports suggesting falsely high levels due to pregnancy. The sharp decline in calcitonin and CEA 2 weeks postoperatively suggested these were truly elevated due to MTC and unaffected by pregnant status. We suggest that calcitonin and CEA be followed similar to non-pregnant cases with MTC. Resources: 1.Khaled, H. M., Lahloubi, N. A., & Rashad, N. (2016). A review on thyroid cancer during pregnancy: Multitasking is required. Journal of Advanced Research, 7(4), 565–570. Presentation: 6/2/2024

7783 Pheochromocytoma Unusually Presenting As Intestinal Pseudo-Obstruction: A Case Report

Abstract Disclosure: J.V. Chua: None. E.C. Cunanan: None. J.G. Sazon: None. J.L. Reyes: None. Introduction: Pheochromocytoma is a rare neuroendocrine tumor that arises from the adrenal medulla. It may present with a variety of symptoms that can resemble other diseases as a result of the effects of catecholamine overproduction on the different organ systems of the body, occasionally making diagnosis difficult and delaying appropriate treatment.Intestinal pseudo-obstruction is an unusual presentation of pheochromocytoma from the effects of excessive catecholamines on the gastrointestinal system, resulting in decreased peristalsis with constriction of the sphincter muscles, consequently prolonging intestinal transit time. Currently, there is no available data on its incidence or prevalence rate. Clinical Case: This is a case of a 50-year-old Filipino male initially presenting with abdominal pain and enlargement with inability to pass stool and flatus, not relieved by laxatives, enemas, and nasogastric and rectal tube decompression. Abdominal radiograph revealed segmental ileus versus partial large bowel obstruction, while abdominal CT scan showed fecal impaction and an incidental finding of an enhancing adrenal mass on the left adrenal gland. Colonoscopy findings were unremarkable. Laboratory workup demonstrated elevated 24-hour urine metanephrine levels with a value of 44.62 mg/24 hours (normal value: 0-1.0 mg/24 hours). The patient was initially managed conservatively, but no improvement in symptoms was noted. Pre-operative preparation was done with terazosin and intravenous saline infusion, and the patient then underwent left open adrenalectomy with bowel decompression, which provided resolution of symptoms and resumption of regular bowel movement post-operatively. The final result of the histopathologic examination confirmed the diagnosis of pheochromocytoma. Conclusion: Gastrointestinal symptoms such as ileus and pseudo-intestinal obstruction are uncommon presentations of pheochromocytoma. A high index of suspicion is necessary among patients presenting with these symptoms, and pheochromocytoma should be considered as part of the differential diagnosis. Presentation: 6/1/2024

Risk Factors for Perioperative Complications, Treatment Outcomes and Aggressive Behavior of the Tumor in Patients with Pheochromocytoma

Introduction. Pheochromocytomas are catecholamine-secreting tumors arising from chromaffin cells of the adrenal gland. Surgery is the only curative treatment with a high biochemical cure rate, low mortality and high risk of perioperative complications. Objectives. To study the demographic characteristics of patients with pheochromocytoma and to identify the risk factors for perioperative complications, treatment outcomes, and aggressive behavior of the tumor. Methodology. We retrospectively studied the data of pheochromocytoma patients registered from 2012 to 2022. Results. In our study, a total of 30 patients with pheochromocytoma were included. The mean age of presentation was 35 ± 12.8 years. Fifty-six percent were females, and the sex ratio was 1.3:1. Pheochromocytoma spells (60%) was the most common complaint, followed by abdominal pain (53%), orthostatic complaints (10%) and incidentalomas (6%). The baseline mean 24-hour urinary total metanephrines was 2963.7 ± 2658 mcg/24 hours, and the mean tumor size was 7.3±0.53 cm. Forty-three percent of patients underwent laparoscopic adrenalectomy, while the rest underwent open surgery. The mean Pheochromocytoma of Adrenal gland Scaled Score (PASS) was 3.41 ± 0.28, and 23% had a high risk for malignancy. Among perioperative complications, hypertension crisis (17%) was the most common, followed by posoperative hypotension (13%), hypoglycemia (3%) and right-sided pneumothorax (3%). These patients with complications had higher metanephrine levels (5490 vs. 1880mcg/24 hours, p=0.001). Blood pressure normalized in 50%, and this was associated with male sex, younger age (29.5 vs. 40 years, p=0.03), higher metanephrines (4619 vs. 1855mcg/24 hours, p=0.001) and smaller tumors (5.91 vs. 8.61cm, p=0.046). PASS score greater than or equal to 4 was associated with higher metanephrine levels (5104 vs. 2312mcg/24 hours, p=0.021) and larger tumors (9.28 vs. 6.68 cm, p=0.024). Biochemical cure rate was achieved in 76% of patients after surgery and was associated with older age (37.7 years vs. 27.7 years, p=0.047) and absence of pheochromocytoma spells (100% vs. 61%, p=0.014). Conclusion. Young age, smaller tumor size and higher metanephrine concentrations were associated with normalization of blood pressure post-surgery. On the other hand, older patients and those without pheochromocytoma spells had better biochemical cure rates. Patients with higher baseline metanephrine levels had increased perioperative complications. More aggressive tumor behavior was associated with higher metanephrine levels and larger tumors. Sex, baseline blood pressure and mode of surgery did not have any influence on treatment outcomes.

Ischaemic stroke as the initial presentation of a pheochromocytoma associated with neurofibromatosis type 1

Pheochromocytoma is a rare but well-recognised manifestation of neurofibromatosis type 1 (NF1). Ischaemic stroke has been rarely reported in patients with pheochromocytoma. It can be due to either hypertension or vasospasm. A 33-year-old woman presented with ischaemic stroke and was evaluated for young stroke. Examination revealed clinical diagnosis of NF 1. She had persistent regular tachycardia and mild hypertension. But she denied features suggestive of pheochromocytoma spells. 24-hour urinary metanephrine level was elevated and there was large left adrenal mass lesion. She underwent left sided adrenalectomy. Histology further confirmed the diagnosis of pheochromocytoma. There should be a lower threshold to suspect pheochromocytoma in patients with NF 1.

Impact of commonly used drugs on 24-hour urine metanephrine excretion.

Impact of commonly used drugs on 24-hour urine metanephrine excretion.

P-06 Catecholamine-induced cardiomyopathy: A rare presentiation of pheochromocytoma

Abstract Introduction Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors. Clinical manifestations consist of various cardiovascular signs and symptoms related to excessive secretion of catecholamines. Catecholamine-induced cardiomyopathy is a rare but life-threatening complication of PPGL. Excessive discharge of catecholamines results in vasoconstriction, coronary vasospasm and myocardial ischemia. Three types of cardiomyopathies can be observed in patients with PPGL; dilated cardiomyopathy, Takotsuba cardiomyopathy and hypertrophic cardiomyopathy. Clinical Case Herein, we present a case with PPGL complicated with heart failure probably due to excessive secretion of catecholamines. A 19 years-old man was admitted to emergency department with dyspnea and hypotension. He exhibited severe signs of heart failure with very high liver function tests; ALT: 3647 U/L (8-65) and AST: 4542U/L (7-40), probably due to hepatic congestion. Echocardiogram performed in ICU reported %10 left venticular ejection fraction with diffuse akinesia. Remarkable improvement of liver function was recorded following the introduction of heart failure medicines. A computed tomography scan that was performed for abdominal pain and distension revealed a six cm tumour at the left adrenal gland compatible with pheochromocytoma. Laboratory analyses were; 24-hour urine metanephrines: 1938mcg (44-261), normetanephrines: 17934mcg (103-390). Following necessary preoperative preparations, laparoscopic left adrenalectomy was performed and a 70 mm adrenal tumor, histopathologically compatible with pheochromocytoma, was excised. His postoperative laboratory findings were; 24-hour urine metanephrines: 248 mcg (44-261), normetanephrines: 4368 mcg (103-390), chromogranin A: 554.9 ng/ml (0-100), 3-methoxytyramine: 0.34 nmol/l (0-0.17). A 68-Ga-DOTA-Peptide PET/CT following 12 weeks of surgery demonstrated hypermetabolic lesions at left suprarenal area. A second open surgery was performed and lymph node metastases were detected (Figure 1). His cardiac functions ameliorated significantly following the removal of tumors. Genetic analysis for PPGL syndromes were negative for KIF1B, SDHB, NTRK1, TMEME127, VHL, RET, SDHD genes. Work-up is still pending for the mutations of SDHA, SDHC and SDHAF2 genes. Conclusion Cathecolamine-induced cardiomyopathy is a rare entity associated with PPGL. Urgent recognition of related clinical signs and symptoms and detection of PPGL is lifesaving. It should be kept in mind in patients presenting with symptoms of heart failure, hypotension and multisystem crisis in the absence of coronary or valvular heart disease.Figure 1.Pheochromocytoma with lymph node metastasis. (H&E x100)

24-hour urine metanephrine excretion in patients diagnosed with adrenal incidentaloma: impact of commonly used drugs on a clinical decision.

Incidentaloma is an adrenal tumor detected during diagnostic imaging performed for extra‑adrenal causes. Evaluation of metanephrine concentrations in a 24‑hour urine collection can be a significant challenge in patients with multiple medications and comorbidities. The aim of this study was to evaluate the effect of commonly used groups of drugs on metanephrine levels in the 24‑hour urine collection. A total of 1051 patients with adrenal mass below 10 Hounsfield units on unenhanced computed tomography were included in the study. Patients diagnosed with Cushing or Conn syndrome, adrenal carcinoma, pheochromocytoma, active extra‑adrenal malignant neoplasms, and exacerbation of severe illnesses were excluded. Metanephrine, normetanephrine, and 3‑methoxytyramine in the 24‑hour urine collection were measured by high‑performance liquid chromatography with electrochemical detection. Information on concomitant medication (β‑blockers, calcium channel blockers [CCBs], loop diuretics, thiazide diuretics, potassium‑sparing diuretics, α‑blockers, angiotensin‑converting enzyme inhibitors / angiotensin II receptor blockers, metformin, nonmetformin antidiabetic drugs [NMADs], lipid‑lowering drugs, proton pump inhibitors, levothyroxine, thyreostatics, antidepressants, neuroleptics, benzodiazepines, glucocorticosteroids, inhaled B‑receptor agonists, and ipratropium) was collected from each patient. The urinary excretion of normetanephrine was significantly higher in the patients on β‑blockers, CCBs, loop diuretics, α‑blockers, NMADs, and neuroleptics. α‑Blockers increased urine metanephrine concentration, and NMADs, antidepressants, and glucocorticosteroids lowered it. There was no association between the analyzed drugs and urinary 3‑methoxytyramine level. Many drug groups interfere with the measurement of urinary fractionated metanephrines. These interactions should be taken into account during interpretation of a hormonal evaluation, as they can be crucial for further management, especially for making a decision on surgical treatment.

Single Stage Bilateral Adrenalectomy (Cortical-Sparing) and Pancreatectomy (Corpus-Sparing) in a Patient with Von Hippel-Lindau Disease.

Von Hippel-Lindau (VHL) disease is an autosomal dominant syndrome and affects many organs. We aim to report an adult patient with VHL disease having bilateral adrenal pheochromocytoma and multiple neuroendocrine tumors of the pancreas who was successfully treated with simultaneous function-preserving adrenalectomy and pancreatectomy. A 27-year-old woman was admitted to hospital with hypertension. The computed tomography of the abdomen revealed a solid tumor in both adrenal glands with the sizes of 12x7 cm on the right and 4x4 cm on the left. She also had two pancreatic solid masses in the head and three in the tail with varying sizes. The laboratory tests are all within normal limits except elevated 24-hour urinary metanephrine and normetanephrine. I-123 MIBG scanning showed increased uptake in both adrenal glands. Fine needle aspiration biopsy of the tumor on head of pancreas via endoscopic ultrasonography showed neuroendocrine tumor. Those findings were compatible with bilateral pheochromocytoma and multiple pancreatic neuroendocrine tumors and genetic tests revealed the mutation which confirmed the diagnosis of VHL disease. After suppression with alpha-1 inhibitor, right total, left cortical-sparing adrenalectomy, Whipple procedure for the pancreatic head lesions and spleen-preserving distal pancreatectomy were performed and pancreatic corpus was preserved. This case showed that multiple function-preserving procedures can be safely performed with oncological principles in patients with VHL disease.

A RARE PRESENTATION OF SMALL CELL LUNG CARCINOMA METASTASIZING TO PHEOCHROMOCYTOMA

Abstract Introduction/Objective Tumor-to-tumor metastasis is a rare phenomenon in which primary tumor cells metastasize hematogenously into another unrelated tumor. We report an interesting case of a tumor-to-tumor metastasis of small cell lung carcinoma to pheochromocytoma of the adrenal gland. Methods/Case Report A 75-year-old female former cigarette smoker with a past medical history of hypertension presented with a two-day history of dyspnea and epigastric pain. Physical examination demonstrated elevated blood pressure only. A computerized axial tomography scan of the chest and abdomen showed an incidental 3.1 cm right adrenal mass and right hilar lymphadenopathy. Detailed biochemical workup showed elevated serum epinephrine, norepinephrine, and 24-hour urine metanephrine. Adrenalectomy showed a 5.8 cm tumor mass with solid lobulated yellow to pink-tan and focally hemorrhagic cut surfaces. Microscopic examination showed a neoplasm composed of two distinct components. The predominant component consisted of nests ("zellballen") of large polygonal cells with variable nuclear pleomorphism, abundant amphophilic to basophilic cytoplasm, and a delicate intervening fibrovascular stroma, without significant mitotic activity. The minor component was characterized by sheets and nests of "small blue cells" with round to ovoid nuclei, stippled nuclear chromatin pattern, scanty cytoplasm, patchy necrosis, and high mitotic activity (>20 mitoses per 10 HPF). Foci of small cell carcinoma deposits were also present in the lymphatic channels of pheochromocytoma. Immunohistochemical stains demonstrated cytoplasmic staining of predominant component tumor cells for synaptophysin, chromogranin, and the absence of staining for TTF-1, CK CAM 5.2, and Ki-67. However, minor component tumor cells demonstrated cytoplasmic staining for synaptophysin, membranous staining for CK CAM 5.2, and nuclear staining for TTF-1 and Ki-67(60%). A final diagnosis of composite pheochromocytoma (predominant) and small cell neuroendocrine carcinoma (minor) was rendered. The possibility of a” collision” tumor comprising primary small cell carcinoma of pulmonary origin metastatic to an adrenal pheochromocytoma in light of the patient's cigarette smoking history and the presence of right hilar lymphadenopathy was favored. The subsequent biopsy of the right subcarinal adenopathy showed small cell carcinoma. Results (if a Case Study enter NA) NA Conclusion To the best of our knowledge, this is the only case of metastasis to a pheochromocytoma from a small cell neuroendocrine lung carcinoma.

An Unusual Cause of Bilateral Adrenal Incidentaloma: A Case Report of Primary Adrenal Lymphoma

Primary adrenal lymphoma (PAL) is an extremely rare among the causes of adrenal incidentaloma. Most were diagnosed with adrenal insufficiency and B symptoms (unexplained weight loss, night sweats, fever). This article presented a 57-year-old woman who was investigated for bilateral adrenal masses found incidentally on computed tomography (CT). Physical examination and laboratory tests revealed no evidence of adrenal insufficiency or B symptoms. Only 24-hour urinary metanephrine and normetanephrine excretion were increased. Tumour F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) scan showed the greatest dimension was 14 cm in the left adrenal mass and the maximum standardized uptake value (SUV max) was 26.1 (relative to mean SUV in the normal liver parenchyma, which was 2). An adrenal biopsy was performed after taking adequate precautions against the possibility of a catecholamine crisis. Histopathology revealed high-grade B-cell lymphoma. Bone marrow involvement and brain metastasis were not observed. She received the R-EPOCH (rituximab, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin) regimen and intrathecal methotrexate therapy as central nervous system prophylaxis. The patient responded well to treatment, and close clinical follow-up continues. PAL should always be considered when a bilateral adrenal mass is detected.

FRI194 Pheochromocytoma Presenting As Catecholamine-Induced Cardiomyopathy: A Case Report

Abstract Disclosure: M. Tsikala Vafea: None. D. Lee: None. Introduction: Pheochromocytoma (PCC) is a rare catecholamine-secreting neuroendocrine tumor presenting with the classic triad of episodic headache, sweating and tachycardia. Catecholamine-induced cardiomyopathy (CICMP) can occur as a complication of PCC in 7-11% of patients. It presents more commonly as dilated cardiomyopathy and inverted Takotsubo cardiomyopathy but also as hypertrophic or unspecified cardiomyopathy. Following appropriate pharmacologic treatment and resection of PCC, these cardiac complications usually resolve. Case report: 36 year old man with history of hypertension presented to the hospital with worsening orthopnea and cough. Following antibiotic treatment failure for suspected pneumonia, he was re-admitted with hemoptysis, tachycardia, hypoxia, and hypertensive emergency. Troponin and brain natriuretic peptide were found to be elevated. CT chest and abdomen showed pulmonary nodules and a large left adrenal mass measuring 9.6x9.3x9.4 cm, concerning for metastatic PCC. He was subsequently started on doxazosin. Transthoracic echo showed bi-atrial enlargement, diffuse severe left ventricle hypokinesis, reduced ejection fraction 25% and diastolic dysfunction. Stress cardiac MRI showed non-ischemic cardiomyopathy, corroborating the diagnosis of CICMP. After achieving adequate alpha-adrenergic blockade, he was started on goal-direct medical therapy consisting of valsartan, metoprolol and empagliflozin. His pulmonary nodular opacities improved on repeat imaging, congruent with pulmonary edema rather than metastases. Plasma and 24-hour urine metanephrines (2,964 pg/mL and 23,310 mcg/24 hr, respectively) and normetanephrines (9,266 pg/mL and 33,927 mcg/24 hr, respectively), as well as dopamine (493 pg/mL), epinephrine (3,205 pg/mL) and norepinephrine (above reportable range of 4,800 pg/mL) eventually came back significantly elevated, confirming his diagnosis of PCC. A month after presentation, he underwent left adrenalectomy, which revealed an 11 cm composite PCC ganglioneuroma. One-month postoperatively, urine metanephrines and normetanephrines were normal but his ejection fraction remained unchanged. Discussion: CICMP should be considered in patients presenting with acute heart failure and an incidental adrenal mass to avoid delays in treatment. Acute pulmonary edema may resemble pulmonary nodules on CT, so interpretation of these findings should correlate with the clinical presentation. Timely initiation of alpha-adrenergic blockade upon suspicion of PCC is crucial as it can significantly improve hemodynamics, and biochemical markers take time to result. 96% of CICMP cases improve after resection of PCC within a variable time frame ranging from one week to several months. Our patient’s CICMP had not improved one month after his adrenalectomy, but it remains to be seen whether he eventually recovers his cardiac function. Presentation: Friday, June 16, 2023