Laparoscopic transperitoneal and retroperitoneal adrenalectomy: a 20-year, single-institution experience with an analysis of the learning curve and tumor size [lap transper and retroper adrenalectomy]

Background The superiority of laparoscopic transperitoneal (TP) versus retroperitoneal (RP) adrenalectomy is an ongoing debate. Methods Data from 163 patients (TP: n = 135; RP: n = 28) undergoing minimally invasive adrenalectomy were analyzed. Both operative [intraoperative blood loss, previous abdominal surgery, conversion rate, operative time and tumor size] and perioperative [BMI (body mass index), ASA (American Society of Anesthesiologists) score, time of hospitalization, time of oral intake, histology and postoperative complications] parameters were compared. Both the learning curve (LC) and tumor size were analyzed. Results We found significant differences in the mean operative time ( p = 0.019) and rate of previous abdominal surgery ( p = 0.038) in favor of TP. Significantly larger tumors were removed with TP ( p = 0.018). Conversion rates showed no significant difference ( p = 0.257). Also, no significant differences were noted for time of hospitalization, intraoperative blood loss and postoperative complications. In terms of the LC, we saw significant differences in previous abdominal surgery ( p = 0.015), conversion rate ( p = 0.011) and operative time ( p = 0.023) in favor of TP. Large (LT) and extra-large tumors (ELT) were involved in 47 lesions (LT: 40 vs. ELT: 7), with a mean tumor size of 71.85 and 141.57 mm, respectively. Mean intraoperative blood loss was 64.47 ml vs. 71.85 ml, time of hospitalization was 5.10 vs. 4.57 days and mean operative time was 76.52 vs. 79.28 min for LT and ELT, respectively. Conclusion A shorter operative time and lower conversion rate in favor of TP were noted during the learning curve. TP proved to be more effective in the removal of large-, extra-large and malignant lesions. The RP approach was feasible for smaller, benign lesions, with a more prolonged learning curve.