A. R. Marcadis1, G. A. Rubio1, Z. F. Khan1, J. C. Farra1, T. M. Vaghaiwalla1, J. I. Lew1 1University Of Miami,Leonard M. Miller School Of Medicine, Division Of Endocrine Surgery, DeWitt Daughtry Family Department Of Surgery,Miami, FL, USA
Introduction: Adrenal gland tumors are categorized into those that produce excess hormones (functional) and those that do not (nonfunctional). Both functional and nonfunctional adrenal tumors can be further subdivided by benign and malignant pathology. Malignant nonfunctional adrenal tumors are rare, with definitive diagnosis often made by final pathology. Furthermore, the morbidity and mortality associated with surgical treatment of such uncommon tumors remains uncertain. This study compares the perioperative in-hospital outcomes after adrenalectomy in patients with benign and malignant nonfunctional adrenal tumors.
Methods: A retrospective cross-sectional analysis was performed using the Nationwide Inpatient Sample database (2006-2011) to identify surgical patients hospitalized for adrenal tumors. Patients who underwent unilateral open or laparoscopic adrenalectomy for nonfunctional adrenal tumors were further subdivided into benign and malignant groups based on final pathology. Patient demographics, socioeconomic and clinical factors, comorbidities, and perioperative complications were evaluated by univariate and risk-adjusted multivariate logistic regression. Data were analyzed using two-tailed Chi-square and t-tests.
Results: Of 28,339 patients who underwent unilateral adrenalectomy for nonfunctional adrenal tumors, 75% (n=21,279) had benign adenomas, while the remaining 25% (n=7,060) had malignancy on final pathology. Patients with malignant nonfunctional adrenal tumors were more likely to be younger in age (46 vs 54 years; p<0.01) and men (61.6 vs 44.6%; p<0.01) compared to patients with benign nonfunctional adrenal tumors. Patients with malignant nonfunctional adrenal tumors were more likely to suffer intraoperative complications including vascular (7.1 vs 3.8%; p<0.01) and splenic injury (5.6 vs 2.1%; p<0.01), postoperative complications including hematoma (3.6 vs 2.0%; p<0.01), shock (1.1 vs 0.5%; p<0.01), acute kidney injury (3.1 vs 2.5%; p<0.01), venous thromboembolism (1.5 vs 0.6%; p<0.01), and pneumothorax (1.6 vs 0.9%; p<0.01), as well as have higher rates of blood transfusion (18.5 vs 7.0%; p<0.01), longer hospital stay (5.9 vs 4.2 days; p<0.01) and higher hospital charges (59,529 vs $45,152; p<0.01) compared to their benign counterparts. Finally, patients with malignant nonfunctional adrenal tumors had a significantly higher in-hospital mortality compared to patients with benign nonfunctional adrenal tumors (1.0 vs 0.4%; p <0.01).
Conclusion: Patients with malignant nonfunctional adrenal tumors have significantly higher perioperative morbidity and mortality compared to their benign nonfunctional counterparts. Men younger than 50 years of age with nonfunctional adrenal tumors have an increased risk for underlying malignancy. Such patients should be counseled and medically optimized in preparation for adrenalectomy, and surgeons should remain vigilant in preventing perioperative complications.