Objectives: To compare perioperative, oncological and functional outcomes of Laparoscopic Transperitoneal Partial Nephrectomy (LTPN) and Retroperitoneal Laparoscopic Partial Nephrectomy (LRPN) for posterior, cT1 renal masses (RMs). Materials and methods: Databases of two urologic institutions applying different laparoscopic surgical approaches on posterior cT1 RMs between June 2016 and November 2018 were retrospectively evaluated. Data on patient demographics, perioperative data and tumor histology were collected and further analyzed statistically. Results: Each group consisted of 15 patients. Baseline characteristics were comparable in each group. When compared to LTPN, LRPN was associated with significantly shorter operative time (OT) (115 min versus 199 min, p < 0.05). No significant differences were detected in the other outcomes. Conclusions: LRPN is associated with a significantly shorter OT compared to LTPN for posterior cT1 RMs. Both surgical approaches are safe, feasible and credible, demonstrating optimal results.

Giant adrenal myelolipoma is a rare, benign, sizable, mesenchymal tumor. Preoperative differential diagnosis from retroperitoneal liposarcoma may be challenging. A 66-year-old female patient was admitted because of a sizable tumor at the right retroperitoneal space, incidentally discovered during abdominal ultrasonography for screening purpose. Preoperative imaging studies were indicative for the diagnosis of a giant adrenal myelolipoma (11.7 × 12.9 cm in size); however, a retroperitoneal liposarcoma could not be excluded. We decided to proceed with tumor's surgical removal by using laparoscopic transperitoneal approach and threedimensional high-definition camera. Intraoperatively, the tumor did not infiltrate surrounding tissues and was surrounded by a thin capsule under which there were sparse, orange-colored spots that resembled adrenal cortex. This finding reinforced the initial and most possible diagnosis of adrenal myelolipoma and we easily enucleated the mass. Postoperative course was uneventful, and the patient demonstrated no recurrence on imaging six months postoperatively. Histology confirmed the diagnosis of giant adrenal myelolipoma, measuring 16.5 x 15 x 6.5 cm.

Non-functional, extra-adrenal, retroperitoneal paraganglioma is a rare, neuroendocrine, and potentially malignant tumor. Its diagnosis and treatment may be challenging. A 69-year-old female patient was admitted because of a left para-aortic, solid, 4.4-cm mass, incidentally discovered during abdominal ultrasonography for screening purposes. Her clinical examination was unremarkable. Preoperative differential diagnosis based on cross-sectional imaging included tumor of neuroendocrine or mesenchymal origin. Hormonal investigation with 24hour urinary catecholamines and metanephrines and plasma-fractionated metanephrines was in the normal range. Following consultation with the endocrinologist and anesthesiologist, the tumor was removed by using the three-dimensional (3D) laparoscopic transperitoneal surgical approach. The perioperative course was uneventful and the patient was discharged on the third postoperative day. Histopathologic findings were consistent with the diagnosis of retroperitoneal extra-adrenal paraganglioma of 5 cm in maximum diameter.