Anatomical changes after prostate cancer surgery are linked to a shorter penis length, but it gradually recovers its normal size after a year, according to new research.
The study, “Changes in penile length after radical prostatectomy: investigation of the underlying anatomical mechanism,” was published in BJU International.
Radical prostatectomy, a surgical procedure meant to remove the prostate gland and tissue surrounding it, is a standard treatment for localized prostate cancer. The main complaints after surgery are urinary incontinence and erectile dysfunction, but many patients also complain that their penis is shorter. While several studies have shown that many men report penile shortening after they undergo surgery, the reasons for this phenomenon remained elusive.
Yoshifumi Kadono from the Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science in Japan, and his colleagues measured the changes in penis length over time before and after radical prostatectomy, and examined the underlying mechanisms for these changes.
For this, the researchers measured the stretched penis length of 102 patients before surgery and 10 days after. Patients were again assessed at one, three, six, nine, 12, 18, and 24 months after undergoing surgery.
The researchers also measured the perpendicular distance from the distal end of the membranous urethra to the midline of the pelvic outlet with magnetic resonance imaging (MRI). These MRI scans were done before surgery, 10 days after surgery, and again at 12 months after surgery.
Results showed that stretched penile length was the shortest at 10 days after surgery, with a mean penile length shortening of 19.9 mm. However, it gradually recovered.
Twelve months after surgery, there was no difference in stretched penile length from its length before men underwent surgery.
In an MRI scan, researchers observed that the distal end of membranous urethra moved proximally at 10 days after surgery, but like the stretched penile length measurements, it returned to the its prior position 12 months after the radical prostatectomy.
The researchers also found that the volume of the removed prostate was a predictor of stretched penile length change 10 days after patients underwent surgery.
“The findings can help inform patients about changes in penile appearance after radical prostatectomy,” Kadono, lead author of the study, said in a news release.