An extensive literature search has few previous reports mentioning robot-assisted surgery for adrenal tumors (RA) that are 10 cm in diameter, and its usefulness and validity are unknown. In this report, we describe adrenal tumors ≥4 cm, including two cases of giant adrenal tumors 10 cm in size were successfully resected by robot-assisted surgery, and discuss their usefulness.

Patient background, perioperative course, and pathology results were tabulated and discussed for five patients with adrenal tumors ≥4cm among the cases who underwent robot-assisted adrenalectomy at our institution from April 2022 to November 2024.

Two of the five patients had adrenal tumors of 10 cm in size, an 11 cm adrenocortical carcinoma and a 9.7 cm adrenal cyst that could not be ruled out a retroperitoneal primary malignancy on the basis of magnetic resonance imaging. In all cases, the console time was no more than 2 hours, and the volume of intraoperative hemorrhage was low and discharged from hospital with no perioperative complications occurred, respectively. The pathological results showed their respective lesions to be adrenocortical carcinoma (with no resection stump) , an adrenal pseudocyst, two metastatic adrenal tumor and a adrenal cyst. A case of adrenocortical carcinoma died of cancer 12 months after surgery.

Robot-assisted adrenalectomy is considered to be safe and highly reproducible, with advantages for treating large tumors in terms of oncology and postoperative recovery. On the basis of a report that collated various definitions of tumor sizes, a diameter of 5 cm or more is considered to be an appropriate definition of a large tumor. On the basis of the present results, the conclusion is that robot-assisted surgery offers major advantages over laparoscopic surgery with adrenal tumors that are 5 cm in diameter.