Robotic surgery in giant multilocular cystadenoma of the prostate: A rare case report

BACKGROUND: Giant multilocular cystadenoma (GMC) of the prostate gland is a very rare benign tumor. Although the benign nature has been known, complete surgical excision is the major treatment consensus because of its high recurrence rate. We report a rare case of GMC with accompanying lower urinary tract symptoms and repeated urine retention initially thought to be symptoms of benign prostatic hyperplasia, which was treated with robot-assisted laparoscopic radical prostatectomy. CASE SUMMARY: A 65-year-old man presented with a 2-year history of lower urinary tract symptoms that had deteriorated gradually within the previous six months, even though he had received treatment with a selective alpha-blocking agent. He had undergone two transurethral resections of the prostate (TURP) at a local hospital during a 4-mo interval because initial ultrasound imaging and prostatic core needle biopsy showed benign prostate hyperplasia. Upon the third recurrence, the patient underwent TURP with a green-light laser at our institution. The diagnosis was a tumor composed of variously sized dilated glandular and cystic structures lined by blended prostatic type epithelia positive for prostate-specific antigen; the final diagnosis was giant multilocular cystadenoma. Magnetic resonance imaging showed a large multilocular retrovesical mass 8.0 cm × 7.3 cm × 6.4 cm, with heterogeneous enhancement. A coexisting malignant part could not be excluded. Considering the high recurrence rate, risk of coexisting malignancy, and possible sequelae of open surgery for radical excision, the patient decided to undergo robot-assisted radical prostatectomy, with good outcomes at the 2-year follow-up. CONCLUSION: Robot-assisted surgery for the treatment of prostate GMC provides another choice for simultaneous attention to disease-control and postoperative quality of life.