The Kilogland: Giant prostatic hyperplasia with incidental prostate adenocarcinoma

Abstract

A 74-year-old man with PSA of 21.1 ng/mL, eGFR of 13 mL/min/1.73 m ² (stage 4 renal disease), and an 889 mL prostate (MRI; transrectal ultrasound estimated 1000 mL ) underwent robotic simple prostatectomy for severe lower urinary tract symptoms, including nocturia and recurrent urinary retention. Adenoma dissection, bladder re-anastomosis, and morcellation resulted in 500 mL blood loss and one transfusion. Pathology revealed stromal/glandular hyperplasia and incidental Gleason 8 (3 + 5) adenocarcinoma (<2 % of tissue, no invasion). At six months, PSA was 0.25 ng/mL, with good continence. This case highlights successful robotic management of massive BPH with incidental malignancy.

1 Introduction

Benign prostatic hyperplasia (BPH) presents in approximately half of patients 60 years or older with 25–50 % of men of these men reporting progressive lower urinary tract symptoms. ^, In extremely rare cases patients may develop a condition known as giant BPH (GPH), defined as a prostate hyperplasia weighing over 500mL. For comparison, the average prostate in men with BPH recognized from autopsy is 33mL, with less than 4 % of men over the age of 70 exceeding values over 100mL. Guidelines provide clear guidance regarding surgical treatment options for patients with prostates >100ml volumes. However, treatment options for patients with giant prostate volumes are poorly characterized and largely the subject of case reports. Here we report a case of a patient with GPH successfully managed with minimally invasive robotic techniques and incidentally identified high risk prostate cancer.

2 Case presentation

A 74-year-old man was referred to our facility with foley catheter dependent acute urinary retention and a history of severe lower urinary tract symptoms including nocturia 4 times per night, weak stream, straining to void, and double voiding, with an International Prostate Symptom Score (IPSS) of 17. He had no hematuria or urinary incontinence. The patient’s medical history included a history of deep vein thrombosis, congestive heart failure, and chronic kidney disease. Preoperative digital rectal exam was remarkable for a very large prostate estimated at greater than 200mL volume with no palpable nodules. Abdominal exam demonstrated a large palpable midline mass superior to the pubic symphysis extending to the level of the umbilicus. Laboratory analyses demonstrated a prostate specific antigen of 21.1 ng/mL and EGFR of 13 mL/min/1.73 m ² .

Diagnostic transrectal ultrasound identified a very large prostate with a calculated volume of 1002mL prostate. Renal ultrasound demonstrated a renal cyst, bilateral hydronephrosis, a trabeculated, thickened bladder wall, and a postvoid residual volume greater than 2 L. Pelvic ultrasonography showed a very large intravesical mass originating from the prostate representing the median lobe of the prostate. A foley catheter was placed to alleviate his urinary obstruction and the patient underwent further workup. Preoperative prostate MRI indicated a significant median lobe hypertrophy displacing the bladder and the rectum ( Fig. 1 The prostate volume was calculated as 889 mL using MRI measurements (approximate dimensions: 13 cm × 11 cm × 12 cm) and ellipsoid method, and a PI-RADS 2 score was assigned. MRI demonstrated no adenopathy, bone abnormalities or other soft tissue abnormalities beyond the prostate. PSA density was 0.03 ng/ mL ² . Prostate biopsy was discussed but ultimately not performed due to the patient’s low PSAD and low PIRADS score. In the subsequent weeks the patient was started on tamsulosin 0.4mg PO daily and finasteride 5mg PO daily but failed several trials of void.

After consultation and discussion of the treatment options, a mutli-port suprapubic robot-assisted simple prostatectomy (RASP) was planned using the Xi DaVinci System. The urachus was incised, and the bladder was dropped to enter the space of Retzius. We created a transverse incision in the anterior dome of the bladder, 1.5–2 cm from the bladder neck, allowing entry into the bladder and visualization of an enormous prostate median lobe along bi-lobar hyperplasia. Both ureteral orifices were identified and displaced in a posterior and cephalad direction by the prostate. A retraction stitch was placed through the median lobe and the adenoma was circumferentially mobilized and separated from the peripheral zone. A combination of blunt dissection, monopolar electrocautery with robotic scissors and bipolar electrocautery with a vessel sealer were used to circumferentially mobilize the transition zone of the prostate. Once the prostate adenoma was removed the bladder neck was anastomosed to the urethra with a double-armed Covidien™ V-Loc™ 3-0 suture. The surgical specimen was placed into a Endo Catch™ laparoscopic bag and then morcellated within the bag using the LiNA™ Xcise cordless laparoscopic morcellator ( Fig. 2 ). After confirming hemostasis, a 20-French 3-way Foley catheter was placed. The bladder was closed in two layers, and filled with 250 mL of saline, and no leaks were observed. The duration of the procedure was 340 minutes with no perioperative complications. The estimated blood loss was 500mL and one unit of blood was transfused. The patient was placed in overnight observation with continuous bladder irrigation (CBI). On postoperative day (POD) 1 CBI was stopped due to minimal bleeding and the patient was discharged on POD 1. On POD 7 the patient was presented to the clinic with bloodless urine. A trial of void was performed and he successfully voided.

Postoperative pathology indicated two foci of incidental Gleason 3 + 5 = 8 prostate adenocarcinoma comprising less than 2 % of the total tissue specimen, with largest foci measuring 9.5mm. An assessment of margin status was not possible due to specimen morcellation. Perineural and angiolymphatic vascular invasion were not identified. Tumor immunohistochemistry showed stromal and glandular hyperplasia ( Fig. 3 ). Prostate tissue removed weighed 690 g. His case was presented at tumor board to address the management of the incidentally discovered Gleason 8 prostate cancer. PSA surveillance vs immediate adjuvant radiation, and transrectal ultrasound with prostate needle biopsies of the peripheral zone were suggested by the tumor board. The patient elected for PSA surveillance with treatment if PSA elevation occurred. On 10-month follow-up, the patient was doing well with complete emptying, no incontinence, resolution of his urinary tract symptoms and no changes in erectile function. His six-month postoperative PSA was stable at 0.25 ng/mL and radiation therapy was not administered.