Presentation, Management, and Outcomes of Patients With Giant Pheochromocytoma.

Abstract

Context: Data on giant pheochromocytomas (PHEOs), defined based on size 10 cm or greater, are scarce.

Objective: This work aimed to compare presentation, management, and outcomes of patients with giant vs non-giant PHEOs.

Methods: A retrospective cohort study was conducted in a referral center from 2000 to 2023. Consecutive patients with giant PHEOs and randomly chosen patients with non-giant PHEO (referents) were studied at a 1:6 ratio. Outcomes included perioperative complications, metastases, and mortality.

Results: Of 828 patients with PHEOs, 31 (3.7%) had giant PHEO (median size 12 cm, interquartile range [IQR] 10.0-13.5 cm). In comparison to referents (n = 186, median size 4 cm, IQR, 2.9-5.0 cm), patients with giant PHEO had more symptoms of catecholamine excess (median of 2 vs 1; P = .04) and presented with a higher prevalence of severe catecholamine excess (76% vs 30%; P < .0001). Adrenalectomy was performed in 94% of patients with giant PHEOs and 100% of referents. In addition to preoperative α-adrenergic blockade (89%), metyrosine was used in 14 (7%) patients, mostly in patients with giant PHEOs (26% vs 3%; P < .0001). Patients with giant PHEOs had a higher perioperative complication rate (31% vs 10%; P = .004). During a median follow-up of 3 years, metastases developed at a higher rate in patients with giant PHEOs (45% vs 4% in referents; P < .0001). Disease-specific mortality was 7% in patients with giant PHEOs and 0% in referents (P = .02).

Conclusion: Patients with giant PHEOs compared to referents were more symptomatic, had a higher degree of catecholamine excess, and had a higher rate of perioperative complications. Almost half of patients with giant PHEOs developed metastases, warranting close follow-up.