Randomized Clinical Trial of Posterior Retroperitoneoscopic Adrenalectomy Versus Lateral Laparoscopic Adrenalectomy

Randomized Clinical Trial of Posterior Retroperitoneoscopic Adrenalectomy Versus Lateral Transperitoneal Laparoscopic Adrenalectomy With a Five-year Follow-up

Laparoscopic adrenalectomy has become the gold standard operation for non-malignant adrenal tumors replacing open adrenalectomy. The most popular lateral transperitoneal laparoscopic adrenalectomy (LTLA) approach has been recently challenged by an increasing popularity of the posterior retroperitoneoscopic adrenalectomy (PRA) approach which is believed by many surgeons as an easy to learn, reproducible and beneficial for patients. However, this belief is not evidence-based, so far. The aim of this study is to clarify if PRA is superior to the LTLA as minimally invasive approach to small and benign adrenal tumors.

Laparoscopic adrenalectomy has replaced open adrenalectomy as the standard operation for non-malignant adrenal tumours. Thanks to the popularization of the posterior technique described by Walz and co-workers, the posterior retroperitoneal adrenalectomy (PRA) is being performed in increasing numbers worldwide. Advocates for the laparoscopic and retroperitoneoscopic approaches cite the advantages of each technique, but there is no published evidence that supports the superiority of one over the other. Most of the published literature is retrospective, with inadequate or no controls and with potential biases.

The aim of this study is to test the hypothesis that PRA is superior to the lateral transperitoneal laparoscopic adrenalectomy (LTLA) as minimally invasive approach to small and benign adrenal tumors.

For a sample size calculation an assumption was made that a 20% reduction in duration of surgery represents clinically relevant difference. To detect this, it was calculated that 24 patients would be required in each treatment arm to give the study a power of 90 per cent. Anticipating a 25% loss to follow-up, 32 patients per arm were required in the study.

Inclusion Criteria:

• unilateral adrenal tumor below 7cm in diameter without suspicion for malignancy

Exclusion Criteria:

• active malignancy
• pregnancy or lactation
• age below 18 years, or above 80 years
• high-risk patients according to the American Society of Anesthesiology (ASA 4 grade or higher
• inability to comply with the scheduled follow-up protocol