Long-term transition of urinary status after robot-assisted radical prostatectomy

Abstract

To clarify and statistically analyze the long-term transition of urinary condition and quality of life (QOL) after robot-assisted radical prostatectomy (RARP) using some self-report questionnaires. From May 2017 to June 2021, 243 patients who underwent RARP for prostate cancer at Chiba Tokushukai Hospital were investigated retrospectively. The urinary status was observed for 5 years after surgery using the Core Lower Urinary Tract Symptom Score (CLSS), International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), and International Continence Control Questionnaire-Short Form (ICIQ-SF). We used storage (IPSS-S) and voiding (IPSS-V) items separately for analysis. IPSS-S included “frequency”, “urgency”, and “nocturia”, and IPSS-V included “incomplete emptying”, “intermittency”, “weak stream”, and “straining”. The association between the results of the questionnaire and postoperative urinary continence and QOL was examined by statistical analysis. Median values of follow-up duration were 65.5 months. Items in almost all questionnaires showed the worst points 1 month after surgery and recovered thereafter. All items showed recovery to the baseline level except for “urgency incontinence” and “stress incontinence”. Preoperative IPSS-S > 7 was significantly associated with “pad-free” and “1 pad per day” status in multivariate analysis (Hazard ratio = 0.50 and 0.60, P < 0.01 and < 0.01, respectively). Urinary problems other than urinary incontinence can be restored to the baseline level after RARP. QOL differed between patients who showed a “pad-free” status and “1 pad per day” status. Additionally, preoperative IPSS-S was suggested to be a predictor of both “pad-free” status and “1 pad per day” status after surgery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11701-026-03146-6.

Introduction

Since the introduction of robot-assisted radical prostatectomy (RARP) in 2001 [1], surgical treatment of prostate cancer has shifted from open radical prostatectomy (ORP) to RARP. Compared with ORP, RARP is superior to ORP not only in cancer control but also in terms of postoperative urinary continence and quality of life (QOL) [2, 3]. Recently, the 10-year survival rate after surgery was reported to be 97.9% [4]. However, many reports were follow-up studies of 1 to 2 years, and the long-term QOL and urinary condition of men after RARP are largely unexplored. Therefore, evaluating the long-term urination status and QOL after RARP has clinical value.

Many self-reported questionnaires are used to assess urination status in clinical practice [5–8]. They are convenient and provide information on longitudinal data of patients’ subjective complaints. We used multiple types of questionnaires and investigated the long-term transition of urinary condition and QOL after RARP. In addition, the association between the results of the questionnaire and postoperative urinary continence and QOL was examined.

Methods

Patient characteristics and surgical approach

From May 2017 to June 2021, 243 patients who underwent RARP for prostate cancer at Chiba Tokushukai Hospital were investigated retrospectively. The da Vinci surgical robot system (da Vinci-Si and -Xi®: Intuitive Surgical Incorporation, Sunnyvale, CA) was used for RARP by a transperitoneal approach as previously described [9]. Lymph node dissection was basically indicated in patients with a Briganti nomogram [10] > 15% or ISUP grade ≥ 4 or suspected lymph node metastasis based on imaging findings. At the patient’s request, nerve-sparing was performed on the side where nerve preservation was deemed possible based on the results of the magnetic resonance imaging (MRI) and biopsy findings.

"Chiba Tokushukai Hospital Ethics Committee" (TGE01722-017) approved the present study, and the present study was conducted in line with the Helsinki Declaration. This study was conducted in an opt-out format.

Postoperative follow-up and questionnaire collection methods

The standard postoperative follow-up protocol was patient visits at 1-, 3-, 6-, and 12 months after surgery, and every 6 months thereafter. All patients were asked to complete self-administered questionnaires of the core lower urinary tract symptom score (CLSS), the international prostate symptom score (IPSS), the overactive bladder symptom score (OABSS), and the international continence consultation questionnaire-short form (ICIQ-SF) at 1-, 3-, 6-, 12-, 36-, and 60 months after surgery. Recovery of postoperative urinary incontinence was confirmed verbally in the outpatient clinic by checking the number of pad-use.

CLSS and IPSS were used to assess lower urinary tract symptoms (LUTS) [5, 6]. IPSS-QOL > 4 was defined as severe IPSS-QOL [11]. We used storage (IPSS-S) and voiding (IPSS-V) items separately for analysis. IPSS-S included “frequency”, “urgency”, and “nocturia”, and IPSS-V included “incomplete emptying”, “intermittency”, “weak stream”, and “straining”. [12] OABSS and ICIQ-SF were used to assess overactive bladder (OAB) and urinary incontinence [7, 8].

Since the results of the questionnaires were ordinal variables, and the median values were not representative enough to accurately represent the results, the mean values were used in Fig. 1.

Fig. 1.

The results of each questionnaire over time for the entire cohort. (a) CLSS (b) IPSS (c) OABSS (d) ICIQ-SF. Mean values were used in the figures of results on questionnaires

Pairwise deletion was used to handle the missing data because the aim was to utilize the collected data as much as possible. Questionnaire completion rates at each time point are shown in Table S1.

Sub-analyses based on the number of pads

Sub-analyses were performed based on pad status after surgery. Patients were classified into 3 groups and the questionnaires were compared: those who achieved complete urinary continence (pad-free) status within 5 years (group 1), those who achieved social continence (1 pad per day) status within 5 years (group 2), and those who did not recover from urinary incontinence (2 or more pads per day) status within 5 years (group 3).

Statistical methods

Data were analyzed using the EZR software (Jichi Medical University Saitama Medical Center, Saitama, Japan), a graphical user interface for R (The R Foundation for Statistical Computing, Vienna, Austria). Mann–Whitney U test and Bonferroni correction were used for sub-analyses. Cox hazard regression models were used to examine the association between urinary continence recovery and factors. Multivariate logistic regression models were used to examine the association between severe IPSS-QOL (IPSS-QOL > 4) and risk factors. In Table 1, 2, S7 and S8, preoperative IPSS-S and IPSS-V were used for analysis. In Table S6, scores on CLSS items each month after surgery were used for analysis. The cutoff value was defined based on the quartile. Statistical significance was defined as a P-value less than 0.05 when two groups were compared and less than 0.0167 when comparing three groups (Bonferroni correction).

Table 1.

Patients’ characteristics and surgical outcome of the entire cohort (N = 243)

Variable
Follow-up duration (months) (IQR)	65.5 (46.6–77.8)
Age (years) (IQR)	74 (69–78)
BMI (kg/m2)	23.7 (21.9–25.8)
Prostate weight (g)	48 (39–60)
Nerve-sparing (number) Unilateral Bilateral	106 32
Clinical T stage (number)  < cT3  ≥ cT3	212 31
Pathological T stage (number)  < pT3  ≥ pT3	194 49
The number of died within the period	15
PSA (ng/mL) (IQR)	7.6 (5.5–11.3)
Operative time (minutes) (IQR)	278 (233–324)
Console time (minutes) (IQR)	215 (174–259)
Surgeon volume (number) (IQR)	77 (45–137)
Lymph node dissection (number)	68
Estimated blood loss (mL) (IQR)	150 (100–250)
Preoperative IPSS score (IQR) Total IPSS-S IPSS-V	8 (4–14) 4 (2–7) 4 (1–7)
Condition of urinary continence recovery within 5 years (number) (%) Pad-free (group 1) One pad per day (group 2) Two or more pads per day (group 3)	177 (72.8) 44 (18.1) 22 (9.0)

IQR; interquartile range, BMI; body mass index, PSA; prostate-specific antigen, IPSS; international prostate symptom score, IPSS-S; IPSS-storage, IPSS-V; IPSS-voiding

Table 2.

Univariate and multivariate analyses of variables and factors associated with urinary continence recovery

	Univariate analysis		Multivariate analysis
	Hazard ratio	P-value	Hazard ratio	P-value
“Pad-free” status
Age > 75 years	0.70 (0.51–0.96)	0.02	0.74 (0.53–1.02)	0.06
Nerve sparing	1.16 (0.93–1.45)	0.16
BMI ≥ 25 kg/m2	0.91 (0.66–1.24)	0.55
≥ cT3	0.79 (0.49–1.26)	0.33
≥ pT3	1.09 (0.75–1.58)	0.64
Prostate weight > 60 g	0.67 (0.46–0.96)	0.03	0.69 (0.47–1.01)	0.05
Lymph node dissection	0.85 (0.60–1.18)	0.33
Preoperative total IPSS > 14	0.68 (0.46–1.01)	0.05
Preoperative IPSS-S > 7	0.47 (0.30–0.74)	< 0.01	0.50 (0.32–0.78)	< 0.01
Preoperative IPSS-V > 7	0.91 (0.65–1.27)	0.60

“One pad per day” status
Age > 75 years	0.62 (0.47–0.83)	< 0.01	0.65 (0.49–0.87)	< 0.01
Nerve sparing	1.07 (0.88–1.31)	0.45
BMI ≥ 25 kg/m2	1.11 (0.84–1.46)	0.45
≥ cT3	0.96 (0.64–1.44)	0.85
≥ pT3	1.23 (0.88–1.72)	0.21
Prostate weight > 60 g	0.69 (0.50–0.95)	0.02	0.73 (0.52–1.02)	0.07
Lymph node dissection	0.78 (0.58–1.06)	0.11
Preoperative total IPSS > 14	0.68 (0.48–0.96)	0.02
Preoperative IPSS-S > 7	0.56 (0.39–0.80)	< 0.01	0.60 (0.41–0.87)	< 0.01
Preoperative IPSS-V > 7	0.87 (0.64–1.17)	0.36

BMI; body mass index, IPSS; international prostate symptom score, IPSS-S; IPSS-storage, IPSS-V; IPSS-voiding, Cox proportional hazard models were used in univariate and multivariate analyses. A P-value of < 0.05 was considered to indicate a statistically significant difference

Results

Patient characteristics and status of urinary symptoms

Median values (IQR) of follow-up duration, age, body mass index (BMI), prostate weight, console time, preoperative total IPSS, preoperative IPSS-S, and preoperative IPSS-V were 65.5 months (46.6–77.8), 74 years (69–78), 23.7 kg/m² (21.9–25.8), 48 g (39–60), 215 min (174–259), 8 (4–14), 4 (2–7), and 4 (1–7), respectively (Table 1). One hundred and seventy-seven (72.8%) and forty-four (18.1%) achieved “pad-free” status and “1 pad per day” status within 5 years (Table 1).

Longitudinal changes of urinary symptoms after RARP

In the entire cohort, items in almost all questionnaires showed the worst points 1 month after surgery and recovered thereafter (Fig. 1, S1, and Table S2−5). All items showed recovery to the baseline level except for “urgency incontinence” and “stress incontinence” (Fig. 1a and 1c). Notably, “urinary stream”, “incomplete emptying”, and “total IPSS” were improved after surgery (Fig. 1a, 1b, and Table S2−3). “Stress incontinence” persistently showed as the worst item in over 20% of the patients in the entire cohort, while the ratio of “urgency incontinence” gradually decreased (Fig. 2a).

Fig. 2.

Proportion of the worst item in CLSS each month after surgery. (a) Entire cohort (b) Classified by postoperative urinary continence condition. (Top): achieving “pad-free” within 5 years. (Middle): achieving “1 pad per day” within 5 years. (Bottom): “2 or more pads per day” (no recovery of urinary continence within 5 years)

In the sub-analyses comparing patients among groups divided by pad status, the ratio of “urgency incontinence” as the worst item gradually decreased in patients with “pad-free” status (group 1) whereas “urgency incontinence” persistently weighed heavily in patients with 2 or more pads per day (group 3) (Fig. 2b). Notably, over 25% of the patients in group 3 complained of urinary leakage “all the time” after surgery (Fig. S2).

Univariate and multivariate analysis identifying associated factors of urinary continence recovery

In the univariate analysis, age > 75 years, prostate weight > 60 g, and preoperative IPSS-S > 7 were significant factors associated with both “pad-free” and “1 pad per day” status (Table 2 and Fig. S3). In the multivariate analysis, preoperative IPSS-S > 7 was the only factor that remained significantly associated with both “pad-free” (Hazard ratio = 0.50, P < 0.01) and “1 pad per day” (Hazard ratio = 0.60, P < 0.01) (Table 2). Age > 75 years was also a significant factor for “1 pad per day” (Hazard ratio = 0.65, P < 0.01) (Table 2).

Assessment of QOL after RARP

When we defined severe IPSS-QOL as IPSS-QOL > 4 [11], it was associated with “urgency incontinence” and “stress incontinence” 12 months after surgery. (Table S6) (Odds ratio = 2.02 and 1.97, P < 0.01 and < 0.01, respectively). Sixty months after surgery, severe IPSS-QOL was associated with “nocturia” and “urgency incontinence” (Odds ratio = 2.26 and 2.51, P = 0.04 and 0.01, respectively) (Table S6).

We also investigated preoperative factors that are associated with severe IPSS-QOL. “Severe IPSS-QOL (IPSS-QOL > 4) at 1 month after surgery” was significantly associated with preoperative IPSS-V (Odds ratio = 1.08, P = 0.03) (Table S7), while “severe IPSS-QOL at 60 months after surgery” was significantly associated with lymph node dissection and preoperative IPSS-S (Odds ratio = 2.74 and 1.15, P = 0.02 and 0.04, respectively) (Table S8).

In the sub-analyses dividing three groups according to the pad status, there were no significant differences in IPSS-QOL among all pairs of the three groups at 1 month after surgery (Fig. 3a). However, IPSS-QOL was significantly better in group 1 (pad-free) than in group 2 (1 pad per day) or group 3 (2 or more pads per day) at 12- and 60 months after surgery (Fig. 3c and 3e). Obviously, QOL scores of IPSS and ICIQ-SF showed similar results among the 3 groups (Fig. 3a, c, e vs. Figure 3b, d, f).

Fig. 3.

Comparison of IPSS-QOL and ICIQ-SF-QOL based on urinary continence condition after RARP. (a, b) 1 month after surgery (c, d) 12 months after surgery (e, f) 60 months after surgery. Mann–Whitney U test and Bonferroni correction were used. N.S; not significant, *; P < 0.0167

Discussion

This study is unique since the patients were followed for a long period after RARP (median follow-up time of 65.5 months). The results of the present study also show the impact of RARP on patients’ thinking of daily lives and satisfaction after surgery. Our data provided three interesting insights. In real-world clinical practice, patients often complain about various urinary problems other than urinary incontinence after RARP, but these problems can be restored to the baseline level in most patients. Second, QOL differed between patients who showed a “pad-free” status and “1 pad per day” status. Most importantly, we identified preoperative IPSS-S as a significant predictor of both “pad-free” status and “1 pad per day” status after surgery.

Since prostate cancer is a type of cancer with a long-term prognosis [4], surgeons should consider postoperative QOL as an important element of surgery. Pad weight and the number of pad-use are highly correlated with QOL [13]. However, the definition and assessment of recovery after urinary incontinence in RARP procedures vary among studies [3]. In this study, recovery of urinary continence was assessed by the number of pad-use, but the rate of urinary continence recovery after RARP differs depending on whether recovery of urinary continence is defined as "pad-free" or "1 pad per day" [14]. The present study implies that the QOL after RARP was significantly worse in patients with “1 pad per day” status than in patients with “pad-free” status, showing that patients are not satisfied with even 1 pad per day. Consequently, the status of “pad-free” is considered more important and urologists should aim to achieve "pad-free" status after RARP.

Based on the results of our study, most of the items on the questionnaires showed gradual recovery up to 6–12 months. This duration of time may be the wound-healing period of damage from surgery. Wound healing consists of three phases: inflammation for 3–5 days, proliferation for 2 weeks, and remodeling for 1–2 years, and the strength of the repaired tissue is reduced to 50–80% of that of the normal tissue [15]. Additionally, inflammation of the lower urinary tract tissues induces fibrosis and smooth muscle dysfunction, leading to lower urinary tract dysfunction [16]. Given this, damage to the structure and tissue may cause worsening of urinary conditions after RARP. Accordingly, to achieve better urinary status after RARP, surgeons should make every effort not to cause unnecessary damage to the normal tissue and structures.

“Urgency incontinence” may adversely affect patients’ QOL after RARP more than “stress incontinence”. In general, stress incontinence is the main reason for urinary incontinence after RARP [17]. However, this study showed that many patients with “2 or more pads per day” condition after RARP suffered from “urgency incontinence” (Fig. 2b). Moreover, “urgency incontinence” was associated with severe IPSS-QOL after RARP (Table S6). The mechanism of urinary incontinence after RARP is not fully understood, but the mechanism of urgency incontinence is considered to differ from stress incontinence [18]. The presence of urgency incontinence results in more psychosocial symptoms, poor physical function, and worse QOL [19]. Hence, elucidating the pathogenesis of urgency incontinence after RARP and preventing it may improve patients’ daily lives after RARP.

The present study also showed that preoperative IPSS-S could predict long-term difficulty in urinary continence recovery after RARP (Table 2). Additionally, preoperative IPSS-S was associated with severe IPSS-QOL at 60 months after RARP (Table S8). Previously, we reported that the presence of OAB before surgery was a negative factor for continence 12 months after RARP [20]. Based on the results of our study, the presence of storage symptoms of LUTS may predict not only medium- but also long-term continence recovery after RARP. Unfortunately, the mechanism of OAB has not been fully elucidated, and it is difficult to clarify this mechanism. Many OAB-related factors have been reported, such as detrusor overactivity and urethral sphincter instability (i.e., urethral pressure variation during bladder filling) [21]. Investigation of OAB-related factors involved in the recovery of urinary incontinence after RARP may shed light on this mechanism.

This study demonstrated the long-term urinary condition after the RARP procedure based on self-reported questionnaires. While most reports have focused on the early recovery of urinary incontinence, the present study provides insight into the long-term recovery of urinary problems after RARP. However, this study only focused on the urinary function after RARP and did not evaluate the relationship among cancer control, inflammation, and urinary function. Previous literature has shown that inflammation is associated with the recovery of urinary continence after RARP [22]. Another study by Guzzi et al. proposed a scoring system “prostatic inflammation score” that could predict biochemical recurrence after RARP [23]. Future studies may investigate the relationship among these conditions and show integrative models that can better predict the recovery of continence after RARP.

Supplementary Information

Below is the link to the electronic supplementary material.

Author contributions

All authors have substantially contributed to the design and conception of the study. Data was collected by Yuta Yamada, Naoki Kimura, Shigenori Kakutani, and Kazuma Sugimoto. Naoki Kimura performed the statistical analysis. Yuta Yamada, Naoki Kimura, Yuji Hakozaki, and Kazuma Sugimoto wrote the draft of the manuscript. Koki Sugano, Hikaru Suyama, and Takuya Iwaki contributed to this study by recruiting patients. Haruki Kume supervised the study. All authors checked and approved the final version of the manuscript.

Funding

Open Access funding provided by The University of Tokyo. The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Data availability

The datasets used in the present study are not publicly available since there are multiple ongoing clinical trials based on the same database that are in progress, but they can be used by a reasonable request to the corresponding author.

Declarations

Ethics approval

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by Chiba Tokushukai Hospital Ethics Committee (TGE01722-017).

Consent to participate

Informed consent was obtained through an opt-out fashion that can be confirmed on the homepage of Chiba Tokushukai Hospital (http://www.chibatoku.or.jp).

Competing interests

The authors declare no competing interests.