CLINICAL AND SURGICAL MANAGEMENT OF SPORADIC ADRENAL PHEOCHROMOCYTOMA UNDERGOING LAPAROSCOPIC ADRENALECTOMY: CASE REPORT AND LITERATURE REVIEW

Abstract

Introduction: Pheochromocytoma is a rare catecholamine-producing neuroendocrine neoplasm arising from chromaffin cells of the adrenal medulla, with a prevalence ranging from 0.1% to 0.6% among hypertensive patients and up to 11% to 14% among adrenal incidentalomas (ROMÁN-GONZÁLEZ; PADILLA-ZAMBRANO; VÁSQUEZ JIMÉNEZ, 2021; ANDRADE et al., 2022). Although it represents a surgically curable cause of secondary hypertension, delayed diagnosis exposes patients to high cardiovascular morbidity and mortality and life-threatening adrenergic crises during anesthetic and surgical procedures (PEREIRA et al., 2004). Case Report: We report the case of a 44-year-old female patient referred for labile refractory secondary hypertension associated with the classic triad of paroxysmal throbbing headache, profuse diaphoresis, and tachycardic palpitations, with paradoxical blood pressure worsening following prior isolated beta-blocker therapy. Biochemical workup demonstrated marked elevation of plasma free metanephrines (free normetanephrine of 1,480 pg/mL and free metanephrine of 410 pg/mL) and 24-hour urinary fractionated metanephrines (normetanephrine of 3,120 mcg/24h and metanephrine of 1,150 mcg/24h), confirming mixed noradrenergic and adrenergic hypersecretion (LENDERS et al., 2014). Adrenal-protocol computed tomography and magnetic resonance imaging revealed a 4.6 x 4.1 cm solid left adrenal mass with an unenhanced attenuation of 36 Hounsfield Units (HU), absolute washout of 48.7%, and marked T2-weighted hyperintensity. Following a 14-day preoperative pharmacologic preparation with titrated selective alpha-1 adrenergic blockade using doxazosin (up to 12 mg/day), volume expansion via a high-sodium diet, and sequential addition of a cardioselective beta-blocker (atenolol 50 mg/day) fulfilling Roizen criteria, the patient underwent left transperitoneal laparoscopic total adrenalectomy. Intraoperative hemodynamic stability was maintained, with a transient hypertensive peak during tumor manipulation promptly controlled with sodium nitroprusside and no refractory hypotension following early ligation of the main left adrenal vein. Histopathological and immunohistochemical evaluation confirmed an adrenal pheochromocytoma (positive for chromogranin A, synaptophysin, INSM1, and GATA3, retained SDHB expression, Ki-67 index of 1.5%, PASS score of 3, and GAPP score of 2 — well-differentiated), with negative germline genetic testing (WACHTEL et al., 2020; METE et al., 2022). At 12-month follow-up, the patient remained in complete biochemical remission and normotensive without antihypertensive therapy. Conclusion: Successful management of pheochromocytoma requires early clinical suspicion, biochemical confirmation via fractionated metanephrines, rigorous preoperative alpha-adrenergic blockade prior to minimally invasive adrenalectomy, and long-term surveillance given the metastatic potential inherent to all chromaffin neoplasms (PLOUIN et al., 2016).