Impact of novel techniques on minimally invasive adrenal surgery: trends and outcomes from a contemporary international large series in urology

Objective: To evaluate contemporary international trends in the implementation of minimally invasive adrenalectomy and to assess contemporary outcomes of different minimally invasive techniques performed at urologic centers worldwide. Methods: A retrospective multinational multicenter study of patients who underwent minimally invasive adrenalectomy from 2008 to 2013 at 14 urology institutions worldwide was included in the analysis. Cases were categorized based on the minimally invasive adrenalectomy technique: conventional laparoscopy (CL), robot-assisted laparoscopy (RAL), laparoendoscopic single-site surgery (LESS), and mini-laparoscopy (ML). The rates of the four treatment modalities were determined according to the year of surgery, and a regression analysis was performed for trends in all surgical modalities. Results: Overall, a total of 737 adrenalectomies were performed across participating institutions and included in this analysis: 337 CL (46 % of cases), 57 ML (8 %), 263 LESS (36 %), and 80 RA (11 %). Overall, 204 (28 %) operations were performed with a retroperitoneal approach. The overall number of adrenalectomies increased from 2008 to 2013 (p = 0.05). A transperitoneal approach was preferred in all but the ML group (p < 0.001). European centers mostly adopted CL and ML techniques, whereas those from Asia and South America reported the highest rate in LESS procedures, and RAL was adopted to larger extent in the USA. LESS had the fastest increase in utilization at 6 %/year. The rate of RAL procedures increased at slower rates (2.2 %/year), similar to ML (1.7 %/year). Limitations of this study are the retrospective design and the lack of a cost analysis. Conclusions: Several minimally invasive surgical techniques for the management of adrenal masses are successfully implemented in urology institutions worldwide. CL and LESS seem to represent the most commonly adopted techniques, whereas ML and RAL are growing at a slower rate. All the MIS techniques can be safely and effectively performed for a variety of adrenal disease.