Category: Basic Science: BPH/LUTS

MP3-6 - Clinical characteristics and gene expression associated with pre-operative prostate volume in patients undergoing holmium enucleation of the prostate (HoLEP) for benign prostatic hyperplasia.

Thu, Sep 20
4:00 PM - 6:00 PM

Introduction & Objective :

Management of benign prostatic hyperplasia (BPH) currently consists of medication or surgery, however, it is not clear which patients will progress from medical therapy to surgical treatment.  In order to better understand clinical and molecular characteristics of patients with advanced BPH, we examined patients who underwent holmium enucleation of the prostate (HoLEP) for treatment. 


Methods :

Clinical information of patients who underwent HoLEP for treatment of BPH at Banner-University Medical Center Tucson and Banner-University Medical Center South between 2012 and 2015 were reviewed. To examine patient characteristics, logistic and linear regression analysis was performed adjusting for relevant variables. A subset of patients (n=34) without prostate cancer (PCa) were selected for gene expression analysis. RNA was extracted from 1.5mm punches removed from formalin-fixed paraffin-embedded (FFPE) glandular epithelial and stromal tissue samples.  RT-PCR was performed to measure expression of two genes, A2M and TGFB3.


Results :

We identified 146 men without prior diagnosis of PCa, final pathological diagnosis of PCa, or undergone a previous surgical prostate reduction procedure. Body mass index (BMI) was positively correlated with pre-operative prostate volume (p=0.03). In linear regression analysis, association between BMI and prostate volume was strong after adjusting for age and race/ethnicity (Beta=0.28, p=0.001).  Adjusting for comorbidity (diabetes, hypertension, and hyperlipidemia) did not change the association.   


Patients with large pre-operative prostate volume had higher A2M expression compared to patients with smaller volumes (p=0.05) and A2M expression in the stroma was significantly negatively correlated with age at surgery (P=0.006) for Hispanic Americans.  In the older patients (age 70 or older), A2M expression in the gland was positively correlated with pre-operative prostate volume (P=0.01), and TGFB3 expression in the gland was positively correlated with BMI (P=0.007).  In Hispanic Americans, TGFB3 expression in the stroma was significantly correlated with age at surgery (P=0.02).


Conclusions :

Prostate volume is significantly correlated with BMI as well as A2M and TGFB3 expression in certain patients.  Patients with elevated BMI and prostate volume may be at higher risk for failure of medical management and progression to surgical treatment.  A2M expression, and TGFB3 expression in Hispanic Americans, were increased in patients with large prostate volumes and may be markers of interest for future studies.  Further research is needed to validate the use of BMI as a screening tool and the role of A2M and TGFB3 in the disease process. 

Joel T. Funk

Associate Professor
Division of Urology, University of Arizona College of Medicine
Tucson, Arizona

Joel T Funk is an Associate Professor of Clinical Surgery and Urology at The University of Arizona College of Medicine in Tucson, Arizona. I am an appointed staff member at Banner University Medical Center and specialize in lower urinary tract function and dysfunction including neuro-urology, urinary incontinence (female and male) as well as benign prostatc obstruction and pelvic organ prolapse. I have performed over 700 holmium enucleations of the prostate (HoLEP) and am one of few practitioners in the United States to regularly do more than 100 of these complex cases each year. I also serve as Chief of Surgical Services at Banner University Medical Center South Campus and am Director of Urologic Surgery at the same institution. I also serve as Vice-Chair of Operations in the Department of Surgery.

My current research focuses include outcomes of HoLEP and shortening the learning curve. This includes HoLEP as same day surgery and novel models of surgical technique simulation to improve operative efficiency. I also partner closely with my collegues in Female Pelvic Medicine in developing novel and new techniques utilizing autologous tissue in the correction of complex multi-compartment pelvic organ prolapse.

I serve as a reviewer for Urology and The Journal of Endourology and am the resident ombudsman for the Urologic Surgery residency program at UA-Tucson. In my spare time I enjoy outdoor activities including cycling and off roading racing as well as spending time with my two children and ever patient wife.

Michael C. Phung

Urology Resident
Division of Urology, University of Arizona College of Medicine
Tucson, Arizona

Ken Batai

Division of Urology, University of Arizona College of Medicine
Tucson, Arizona

Kieran A. Hynes

Medical Student
University of Arizona College of Medicine - Division of Urology
Tucson, Arizona

Robert Bell

Pathology Resident
Department of Pathology, University of Arizona College of Medicine
Tucson, Arizona

Erika Bracamonte

Associate Professor, Director of Surgical Pathology
Department of Pathology, University of Arizona College of Medicine
Tucson, Arizona

Elinora T. Price

Research Coordinator
University of Arizona College of Medicine - Division of Urology
Tucson, Arizona

Aye A. Lwin

Urology Resident
Division of Urology, University of Arizona College of Medicine
Tucson, Arizona