Prostate cancer (PCa) is the most common noncutaneous malignancy for men, with an estimated worldwide incidence of 1.4 million per year.¹ For many, robot-assisted radical prostatectomy (RARP) is a common treatment for localized PCa, with common side effects including a 54%–90% rate of erectile dysfunction and a 4%–31% rate of urinary incontinence.^2,3

Less commonly studied side effects, however, are climacturia and penile length shortening. In a study of 62 patients, Parra López et al found that climacturia occurred in 20%–40% of patients following RARP.⁴ However, none of the analyzed parameters could be defined as predictors of climacturia. Similarly, a study of 42 patients by Lee et al found the prevalence of climacturia in radical prostatectomy (RP) patients to be 45%, but again found no significant predictors.⁵ O’Neil et al found that the use of aids in achieving an erection as well as urinary incontinence were associated with climacturia in a study of patients receiving definitive PCa treatment via surgery and/or radiation therapy.⁶ Similarly, penile length shortening is another side effect of RP that impacts many patients but lacks robust literature. Kadono et al found that the mean penile length shortening was 19.9 mm 10 days post-RP.⁷ However, this study of 102 patients found no significant predictor of penile length shortening at 12 months post-RP. Another study by Vasconcelos et al found a statistically significant reduction in penile length by 1 cm after 12 months, wherein penile length recovery was noted at 48 months of followup.⁸ Preserved erectile function was the only predictor of penile length recovery.

While these studies begin to address underrepresented side effects of RP, they are limited by low power and significant heterogeneity in patient populations, and do not provide context for impact on quality of life. As such, we recently surveyed 800 patients who underwent RP to explore the incidence, risk factors, and predictors of recovery associated with climacturia and penile length shortening.

Of these 800 patients, approximately 46% and 37.5% reported experiencing climacturia and penile length shortening, respectively. Risk factors included a lack of bilateral nerve sparing, high body mass index, high prostate weight, and higher pathological stage at the time of RP. While the proportion of patients reporting these effects is significant, when contextualized within PCa treatment and potential for erectile dysfunction and urinary incontinence, less than 5% of patients ranked either climacturia or penile length shortening as a high priority concern. These findings not only add to risk stratification efforts for identifying patients at risk for climacturia and penile length shortening, but also contextualize the importance of these findings within PCa treatment.

Figure 1. Patient concerns of adverse events following radical prostatectomy. BCR, biochemical recurrence. ED, erectile dysfunction. PLS, penile length shortening.

Figure 2. Concern of adverse events compared to risk of recurrence. BCR, biochemical recurrence. ED, erectile dysfunction. PLS, penile length shortening.

Overall, this survey represents the largest cohort of patients examined for risk factors associated with climacturia and penile length shortening following RARP. In contrast to previous explorations and systematic reviews, the present survey of 800 patients identified nerve-sparing status as a risk factor for climacturia. Similarly, in multivariate analysis, preexisting erectile dysfunction (ie preoperative International Index of Erectile Function-5 <22) impedes recovery from climacturia following RARP.

Distinct from climacturia, 59% of patients in our survey reported penile length shortening. This value is similar to that of an initial study by Fraiman et al, illustrating penile shortening >1 cm in 45% of patients undergoing open prostatectomy.⁹ However, more recent explorations by Bergman et al have shown a lack of penile shortening for patients who maintained their erectile function following surgery.¹⁰ This leads to the conclusion that preserving erectile function preserves penile length and girth. In addition to this postoperative phenomenon, this study has also identified body mass index, pathological stage, and prostate weight to be significant predictors of penile length shortening.

It is important to contextualize these outcomes within RP, cancer recurrence, erectile dysfunction, and urinary incontinence. Despite 46% and 37.5% of patients reporting climacturia and penile length shortening, respectively, when patients were asked to rank the importance of these outcomes compared to erectile dysfunction and incontinence, <5% ranked either climacturia or penile length shortening as a high priority following RP (Fig. 1). Furthermore, when asked to rank the importance of these outcomes compared to biochemical recurrence, 5% of patients ranked climacturia as a greater concern, while 12% ranked penile length shortening as a greater concern following RP (Fig. 2). Finally, when asked to assess orgasm-related quality of life, approximately 80% of patients reported that they were mostly satisfied, pleased, or delighted with their orgasm-related quality of life—despite over 45% reporting either climacturia or penile length shortening (Fig. 3).

Figure 3. Orgasm-related quality of life.

Overall, while there is a significant incidence of climacturia and penile length shortening following RP, less than 5% of patients prioritize these risks as high concerns when compared to risks of erectile dysfunction and urinary incontinence. Regardless, patient- and surgeon-modifiable risk factors for these adverse outcomes include a high body mass index, large prostatic volume, a lack of nerve-sparing procedures, and high-risk disease.