PREDICTORS OF PHEOCHROMOCYTOMA SURGERY OUTCOMES USING A PRE-OPERATIVE SEVERITY CLASSIFICATION SCALE: AN INTERNATIONAL STUDY
Pheochromocytomas (PC) may present across a spectrum of clinical severity. We evaluated a PC severity scale (PCSS) in a multinational, multi-institutional study as a predictive tool for post-operative outcomes after adrenalectomy for PC.
We evaluated all patients who underwent adrenalectomy for PC from 2000-2017. We classified patients as follows: Class I- incidentaloma; Class II: asymptomatic + controlled hypertension; Class III: symptomatic + controlled hypertension; Class IV: uncontrolled hypertension or hemodynamic crisis. We obtained all available pre- and intra-operative data, normalized biochemical studies, pathologic results, and discharge information. Non-parametric multivariable regression and analysis of variance (ANOVA) were used for statistical considerations.
A total of 157 patients were included in our study, 48 (+/- 18) yrs, 54% female, BMI 26 ( +/- 3), 57% right sided (6% bilateral), and 34% of whom had a familial disorder. By PCSS the study population consisted of: Class 1 (25%), Class 2 (35%), Class 3 (22%), and Class 4 (18%). Urinary and plasma normetanephrines were the most commonly abnormal test in 91.7 and 98.1% of patients. Endoscopic excision was performed laparoscopically in 56% and robotically in 26%. A total of 5% sustained a ≥Clavien 3a complication. In a multivariable model, PCSS positively correlated with significant history of cardiovascular disease, urinary and plasma epinephrine levels, post-operative complications, and the number of discharge medications; PCSS negatively correlated with family history.
We present results of a PC severity scale as a predictive tool for post operative outcomes. In a multivariable analysis (Table), the 1-4 PCSS scale correlated with pre-operative cardiac and vascular disease and post-operative complications requiring longer hospital stays and prolonged medical therapy. The severity scale may thus serve to easily stratify patients presented with PC into those who are at particular risk of post-operative complications. The study also highlighted that patients with PC may not necessarily be hypertensive and that the degree of hypertension does not correlate well with clinical outcomes.