機器手臂輔助腎上腺切除術治療合併心衰竭之10公分巨大嗜鉻細胞瘤

廖均翰、黃志平

中國醫藥大學附設醫院 泌尿部

Robotic-Assisted Adrenalectomy for a 10-cm Giant Pheochromocytoma in a Patient with Heart Failure

Chun-Han Liao, Chi-Ping Huang

Department of Urology, China Medical University Hospital, Taichung, Taiwan

Introduction:

Pheochromocytomas are rare, catecholamine-secreting neuroendocrine tumors that can present with life-threatening cardiovascular complications, including catecholamine-induced cardiomyopathy resulting in severe heart failure. While surgical intervention is the definitive treatment, managing a giant pheochromocytoma (≥ 10 cm) in a patient with severely compromised cardiac function was an extreme perioperative challenge. Furthermore, the standard preoperative pharmacological preparation—alpha-blockade followed by non-selective beta-blockade—is strictly contraindicated in patients with concurrent chronic obstructive pulmonary disease (COPD) due to the high risk of bronchospasm. We present a challenging case of a 10-cm giant pheochromocytoma commorbided with HFrEF and COPD.

Case:

A 64-year-old male smoker with a history of chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus initially presented with intermittent hot flashes and sweating for four months, accompanied with intermittent dyspnea requiring nasal cannula oxygen supplementation.

On physical examination, the patient presented with diaphoresis and an elevated systolic blood pressure fluctuating between 150 and 160 mmHg. Chest auscultation revealed mild wheezing. Initial laboratory workup revealed markedly elevated 24-hour urine vanillylmandelic acid (VMA) level of 30.66 mg/day(reference range : 1.9-9.8mg/day), while the remaining analytical study was unremarkable, with no electrolyte imbalances. Imaging including computed tomography and magnetic resonance imaging revealed a 9.9 x 8 x 9.6 cm heterogeneous left adrenal tumor with central necrosis. The tumor abutted the spleen and caused downward displacement of the left kidney with prominent collateral vessels around the tumor. An impression of huge pheochromocytoma was made. A chest CT and bone scan were done to exclude the presence of metastatic disease.

Cardiovascular evaluation revealed newly diagnosed heart failure with reduced ejection fraction (HFrEF). Initial echocardiography showed LV eccentric hypertrophy and global hypokinesia with reduced ejection fraction(LVEF) of only 27.43%. Given the patient's underlying COPD and active airway disease, standard beta-blockers were clinically contraindicated. The cardiologist optimized his heart failure regimen using a mineralocorticoid receptor antagonist (MRA), an angiotensin receptor blocker (ARB), and Ivabradine. Careful titration of ivabradine successfully controlled the heart rate and reduced the cardiac workload without compromising airway resistance. Following three months of treatment, the patient's clinical symptoms, notably dyspnea, improved significantly. A follow-up echocardiogram demonstrated a recovery of the LVEF to 53.3%.

The patient subsequently underwent a robotic-assisted left adrenalectomy. Low-pressure pneumoperitoneum of 10mmHg was utilized. During the critical phase of tumor dissection and clipping of multiple engorged collateral vessels and superficialized vessels in left para renal region, intense hemodynamic fluctuations consistent with a catecholamine storm occurred, which were managed with nine intravenous boluses of 0.5 mg nicardipine. No significant hypotension was noted after the adrenal vein was ligated and the tumor was excised. At the end of the operation, the surgical incision was carefully extended to facilitate the intact extraction of the huge specimen without capsular disruption. The resected adrenal tissue was measured 10 x 6 x 5.5 cm in size and 219.3 gm in weight. Grossly, it is tan and elastic. On section, there is a tumor with focal capsule and heterogenous brownish cystic changes.

Antihypertensive medications were discontinued, and intravenous fluid resuscitation was initiated after the operation. The patient's hemodynamic status stabilized without need for vasopressors. Given the underlying newly diagnosed HFrEF, his cardioprotective regimen, including ivabradine and Entresto were carefully maintained.

The pathology report revealed Pheochromocytoma of the Adrenal gland Scaled Score (PASS) of 6. A focus of perineural invasion and lymphovascular permeation are also identified. Ki-67 staining was elevated at up to 4.33%. The surgical margins were completely free of tumor and no periadrenal adipose or capsular invasion was identified.

During the postoperative follow-up period, a surveillance magnetic resonance imaging (MRI) of the abdomen was performed. The MRI revealed linear high-signal-intensity (SI) foci in the left suprarenal space on both T2-weighted and diffusion-weighted imaging (DWI). Postoperative inflammatory or fibrotic changes, the presence of viable residual or locally recurrent tumor could not be definitively excluded. Further imaging and biochemical surveillance are warranted. Conclusion:

This case showed three critical pillars in the management of complex pheochromocytomas. First, in patients presenting with HFrEF and concurrent airway disease (COPD), ivabradine serves as a safe, highly effective alternative to beta-blockers for heart rate control, successfully reversing the cardiomyopathy and converting a prohibitive surgical risk into a viable candidate. Second, with multidisciplinary medical optimization and adequate intraoperative hemodynamic management, robotic-assisted adrenalectomy is both safe and feasible for 10-cm giant tumors, offering minimal blood loss and rapid postoperative recovery. Finally, a surgical success must be balanced with the oncological reality. Even after a successful R0 resection of a giant pheochromocytoma, an elevated PASS score of 6 and a high Ki-67 index require lifelong biochemical and imaging surveillance to monitor for potential recurrence or metastasis.