Patterns of Use and Short-Term Outcomes of Minimally Invasive Surgery for Malignant Pheochromocytoma: A Population-Level Study

Abstract Background: Malignant pheochromocytoma is rare, and there is a scarcity of data on the use of minimally invasive surgery (MIS) for treatment. The aims of this study were to analyze patterns of use of MIS for malignant pheochromocytoma in the U.S. and compare short-term outcomes to those of open adrenalectomy. Methods: Patients with malignant pheochromocytoma undergoing MIS, including laparoscopy, robotic assisted, laparoscopy converted to open, or open adrenalectomy, were culled from the National Cancer Database, from 1998 to 2011. Data were examined using simple summary statistics, X² and student's t tests, Mann-Whitney test, and logistic regression. Results: A total of 36 MIS and 67 open adrenalectomies were identified in 2010-2011. No significant differences were observed between the two treatment groups in demographic characteristics or comorbidities. Preoperative diagnosis of malignancy was made in 52.8 % of MIS and 48.5 % of open patients (p = NS). MIS and open adrenalectomies did not differ with respect to lymph node metastases, vascular invasion, extra-adrenal-extension, and distant metastases (all p = NS). MIS tended to more often be used to perform partial adrenalectomy (38.9 vs. 20.4 % open, p = 0.061); surgical margins, 30-day readmission and mortality rates were similar to open adrenalectomy (all p = NS). Tumors removed via MIS were smaller (48.7 vs. 73.3 mm open, p = 0.003) and associated with a shorter length of stay. Conclusions: A significant proportion of patients with malignant pheochromocytomas underwent MIS, with short-term outcomes which are comparable to those of open surgery. Further studies focused on long-term survival and recurrence are needed to assess the role of MIS in the management of these rare tumors.