Vol 16 No 03 May-June 2019 260 UROLOGICAL ONCOLOGY Impact and Predictive Value of Prostate Weight on the Outcomes of Nerve Sparing Laparoscopic Radical Prostatectomy in Patients with Low Risk Prostate Cancer Dong-Gen Jiang1, Chu-Tian Xiao2, Yun-Hua Mao2, Jian-Guang Qiu2, Jie Si-tu2, Min-Hua Lu2, Xin Gao2* Purpose: To investigate the impact of prostate weight on outcomes of nerve sparing laparoscopic radical prosta- tectomy (LRP) and assess its predictive value on postoperative continence and potency recovery. Materials and Methods: We conducted a retrospective study on the clinical data of 165 patients with low risk prostate cancer (PCa) who underwent nerve sparing LRP. All the patients included had normal preoperative uri- nary and sexual function. The association of prostate weight with perioperative data was assessed using Spearman correlation coefficient. Univariate and multivariate Cox regression analyses were employed to identify prognostic predictors for continence and potency recovery. Results: Increased prostate weight was significantly associated with older age, higher prostate-specific antigen (PSA), lower biopsy and pathological T stage and Gleason score, longer operative time, and higher estimated blood loss (P < .05). The continence rates at the 3rd, 6th, and 12th month after surgery were 63.6% (105/165), 87.9% (145/165), and 95.8% (158/165); and the potency rates were 44.8% (74/165), 62.4% (103/165) and 77.6% (128/165), respectively. Furthermore, multivariate Cox analysis showed that patient age (HR = 0.52, 95% CI: 0.35- 0.76) and prostate weight (HR = 0.54, 95% CI: 0.34-0.86) were independent predictors for continence recovery, while only patient age (HR = 0.66, 95% CI: 0.45-0.96) could independently predict potency recovery. Conclusion: Larger prostate size was correlated with older age, higher PSA, lower tumor stage and grade, longer operative time, and more intraoperative blood loss in low risk PCa patients. Increased prostate weight may inde- pendently predict poor continence recovery after nerve sparing LRP. Keywords: erectile dysfunction; prostatectomy; prostatic neoplasms; prostate size; prognosis; treatment outcome; urinary incontinence INTRODUCTION Following the introduction of anatomic radical pros-tatectomy (RP) by Walsh PC,(1) this procedure has become a routine treatment modality for localized pros- tate cancer (PCa) worldwide. However, incontinence and erectile dysfunction after RP for early stage PCa can significantly affect the quality of life (QOL) of pa- tients, especially for those with preoperative normal po- tency.(2) The intrafascial approach nerve sparing RP has been reported to be apply to low risk PCa patients,(3-5) which enables the dissection of the prostate with limit- ed trauma to the surrounding fascias and the enclosed neurovascular bundle (NVB). Patients who underwent nerve sparing laparoscopic radical prostatectomy (LRP) could achieve accelerated rehabilitation of continence and potency to a high percentage, without unfavorable effect on the oncological outcomes.(5) As the introduction of prostate-specific antigen (PSA) screening and the prevalence of active surveillance, men diagnosed with clinically organ-confined PCa have presented with larger prostate weight.(6) The application of external-beam radiation therapy and brachytherapy in PCa with large gland size is technical- 1Department of Urology, the Seventh Affiliated Hospital of Sun Yat-Sen University, No.628 Zhenyuan Road, Shenzhen 518107, China. 2Department of Urology, the Third Affiliated Hospital of Sun Yat-Sen University, No.600 Tianhe Road, Guangzhou 510630, China. *Correspondence: Department of Urology, the Third Affiliated Hospital of Sun Yat-Sen University, No.600 Tianhe Road, Guangzhou 510630, China. Tel: + 86 20 85252990. Fax: +86 20 85252678. E-mail: urogx@hotmail.com. Received December 2017 & Accepted May 2018 ly limited, which makes RP the treatment of choice.(7,8) Nevertheless, RP for larger prostates is associated with longer operative time, greater blood loss, and higher surgical difficulty.(9-11) There are several published data analyzing the impact of prostate size on perioperative and functional outcomes of RP,(9-14) while no consensus has been reached. To date, the effect of prostate size on outcomes of nerve sparing LRP remains unclear. The purpose of our study was to explore the association of prostate weight with perioperative data of patients with low risk PCa, and assess the predictive value of prostate weight on continence and potency recovery after nerve sparing LRP. MATERIALS AND METHODS Enrollment This study was conducted after the approval of the Eth- ics Committee of the Third Affiliated Hospital of Sun Yat-Sen University (No. [2015] 2-130). We retrospec- tively reviewed the records of PCa patients from the PCa database of our hospital, and those without com- pleted clinical data were excluded from the research population. Between January 2002 and December 2014, a total of 967 men underwent LRP at our institution, 165 consecutive low risk PCa patients with preopera- tive normal urinary and sexual function who received nerve sparing LRP were included in the study. Low risk PCa was identified according to the D'Amico risk stratification scheme (clinical T stage ≤ cT2a, PSA < 10 ng/mL, and a Gleason score < 7).(15) The 2002 Ameri- can Joint Committee on Cancer TNM staging system was applied for both clinical and pathological staging. Gleason score was evaluated according to the Interna- tional Society of Urological Pathology 2005 guidelines. (16) LRP specimen was submitted in their entirety and prostate weight, which included the prostate, seminal vesicles, and vasa deferentia stumps, was measured at the time of pathological examination by the patholo- gist. No patient had contraindications for general an- esthesia and all the procedures were performed by one experienced surgeon (Xin Gao). Written consent from patients of the study cohort was considered, while as this was a retrospective study in which most of the data were obtained more than 5 years ago and all data were analyzed anonymously, it was considered not needed. Surgical Technique The patient positioning, trocar placement, and the major steps of the surgery have been previously described in detail.(5,17) We focus here on the pivotal surgical essen- tials of our technique. All the patients included received a bilateral intrafascial nerve sparing approach, the intra- fascial plane is developed between the prostatic fascia and the capsule after the posterior plane is developed. The prostatic fascia is incised by sharp and athermic dissection from prostate capsule to facilitate complete mobilization and lateralization of the NVB off the pros- tate. To be noted, the dissection is initiated at the middle of the prostate and continued in a retrograde direction towards the base of prostate to completely detach the NVB from the prostatic pedicles. Then the prostatic pedicles are clipped by Hem-o-lok® clips and detached with athermic scissor without injuring the NVB. Subse- quently, the dissection plane is continued in a descend- ing manner towards the apex. Before vesicourethral anastomosis, an approximate 15-cm long absorbable self-retaining suture (QuillTM SRS) with one five- eighths arc needle is prepared. The bladder neck is first- ly narrowed with running suture from the dorsal edge to form a “tennis racket” shape. Then the continuous suture of the anastomosis is initiated by passing the nee- dle from the outside in on the full thickness of bladder neck and then from the inside out on the full thickness of the urethra at 4 o’clock position. Subsequently, the running suture is continued at 6, 8, 10, 12 and 2 o’clock position, respectively, to complete the vesicourethral anastomosis. Postoperative Care The urethral catheter was removed in case no anasto- motic leakage was detected using cystography. After catheter removal, patients were guided to carry out dai- ly pelvic floor muscle training. All the patients received phosphodiesterase 5 inhibitors (PDE5-Is) (sildenafil 25mg per day) for the first eight weeks postoperatively and thereafter as subjectively needed. Besides, rehabil- itation using vacuum erection device was also recom- mended 3 weeks after the surgery once they returned to continence. Outcomes Assessment Urinary and sexual functions were evaluated with self-administered validated questionnaires preopera- tively and at the 3rd, 6th, and 12th month after surgery, and then simultaneously during the follow-up visits or telephone interviews. All answers were collected by a special independent research staff member. Urinary function was assessed using International Continence Society questionnaire and continence was defined as no pad or a protective pad daily. Sexual function was evaluated by the use of Sexual Health Inventory for Men (SHIM) questionnaire,(18) which is a shortened five-question version of the International Index of Erectile Function. Potency was defined as SHIM score ≥ 21, with or without the use of oral PDE5-Is. Com- Impact of prostate weight on nerve sparing LRP-Jiang et al. Table 1. Correlation between prostate weight and preoperative characteristics of the 165 patients with low risk prostate cancer. Variables Total (%) Prostate Weight r P-value < 75 g (%) ≥ 75 g (%) All cases 165 (100) 124 (75.2) 41 (24.8) - - Age (year) .369 < .001 < 65 89 (53.9) 80 (64.5) 9 (22.0) ≥ 65 76 (46.1) 44 (35.5) 32 (78.0) BMI ( kg/m2) -.116 .137 < 24 72 (43.6) 50 (40.3) 22 (53.7) ≥ 24 93 (56.4) 74 (59.7) 19 (46.3) Preoperative PSA (ng/mL) < 7 78 (47.3) 65 (52.4) 13 (31.7) .179 .021 7-10 87 (52.7) 59 (47.6) 28 (68.3) Comorbidities .010 .901 0 54 (32.7) 41 (33.1) 13 (31.7) 1 79 (47.9) 59 (47.6) 20 (48.8) ≥ 2 32 (19.4) 24 (19.3) 8 (19.5) Clinical T stage -.166 .034 ≤ cT1c 115 (69.7) 81 (65.3) 34 (82.9) cT2a 50 (30.3) 43 (34.7) 7 (17.1) Biopsy Gleason score < 6 29 (17.6) 17 (13.7) 12 (29.3) -.177 .023 6 136 (82.4) 107 (86.3) 29 (70.7) Abbreviations: BMI, body-mass index; PSA, prostate-specific antigen. Urological Oncology 261 Vol 16 No 03 May-June 2019 262 plications occurring during the surgical procedure or within 3 months after surgery were documented and classified according to the modified Clavien grading system.(19) Positive surgical margin (PSM) was defined as the presence of tumor tissue on the inked surface of the specimen. Statistical Analysis The data were analyzed using IBM Statistical Package for the Social Science (SPSS Inc, Chicago, Illinois, USA) version 20.0. Continuous parametric variables were presented as the median value and interquartile range. The association between prostate weight and perioperative data of the patients were evaluated by Spearman correlation coefficient. Univariate and mul- tivariate analysis using Cox proportional-hazards re- gression model were performed to identify independent prognostic predictors for continence and potency recov- ery during the follow-up. All tests of significance were two sided, and P < .05 indicated statistical significance. RESULTS Association between Prostate Weight and Preoperative Characteristics The median patient age was 65 (61-68) years, Body Mass Index (BMI) was 24 (22-27) kg/m2, preoperative PSA was 6.9 (5.3-8.6) ng/mL, and prostate weight was 48 (27-74) g. As showed in Table 1, after assessing by Spearman correlation coefficient, prostate weight was found to be significantly associated with patient age (r = .369, P < .001), preoperative PSA level (r = .179, P = .021), clinical T stage (r = -.166, P = .034) and biopsy Gleason score (r = -.177, P = .023). Patients with large prostate weight were likely to have older age, higher PSA level, and earlier tumor stage. However, no re- markable correlation was observed between prostate weight and BMI, as well as preoperative comorbidities (P > .05). Correlation of Prostate Weight with Perioperative and Pathological Outcomes The perioperative patient data and pathological out- comes are demonstrated in Table 2. The median opera- tive time was 207 (185-236) mins, estimated blood loss was 245 (150-400) mL, hospital stay was 12 (11-14) days and catheterization time was 9 (8-11) days. The bilateral nerve sparing procedures were conducted in all cases. Despite the described strict inclusion criteria, tumors with pathological T stage > pT2b were demonstrated in 25 (15.2%) patients. Similarly, tumors with patholog- ical Gleason score > 7 were found in 9 (5.5%), while the incidence of PSM was only 9.7% (16/165). In the Spearman correlation coefficient analysis, larger pros- tate weight was remarkably correlated with longer op- erative time (r = .221, P = .004), more estimated blood loss (r = .179, P = .022), lower pathological T stage (r = -.168, P = .031) and Gleason score (r = -.181, P = .020). Whereas no significant association was found between prostate weight and blood transfusion, hospital stay, catheterization time, perioperative complications, and PSM (P > .05). Predictive Value of Prostate Weight on Continence and Potency Recovery The median follow-up was 44 months with a range of 13-113 months. During the follow-up period, the conti- Table 2. Association of prostate weight with perioperative and pathological outcomes of the 165 patients after LRP. Variables Total (%) Prostate Weight r P-value < 75 g (%) ≥ 75 g (%) All cases 165 (100) 124 (75.2) 41 (24.8) - - Operative time (min) .221 .004 < 200 80 (48.5) 68 (54.8) 12 (29.3) ≥ 200 85 (51.5) 56 (45.2) 29 (70.7) Estimated blood loss (mL) .179 .022 < 250 86 (52.1) 71 (57.3) 15 (36.6) ≥ 250 79 (47.9) 53 (42.7) 26 (63.4) Blood transfusion .062 .429 No 160 (97.0) 121 (97.6) 39 (95.1) Yes 5 (3.0) 3 (2.4) 2 (4.9) Hospital stay (day) .095 .226 < 12 82 (49.7) 65 (52.4) 17 (41.5) ≥ 12 83 (50.3) 59 (47.6) 24 (58.5) Catheterization time .060 .441 < 9 73 (44.2) 57 (46.0) 16 (39.0) ≥ 9 92 (55.8) 67 (54.0) 25 (61.0) Perioperative complications .122 .119 None 134 (81.2) 104 (83.9) 30 (73.2) Clavien I-II 27 (16.4) 18 (14.5) 9 (22.0) Clavien III-IV 4 (2.4) 2 (1.6) 2 (4.8) Pathological T stage -.168 .031 pT2a 92 (55.8) 63 (50.8) 29 (70.7) pT2b 48 (29.1) 40 (32.3) 8 (19.5) ≥ pT2c 25 (15.2) 21 (16.9) 4 (9.8) Pathological Gleason score -.181 .020 < 7 122 (73.9) 86 (69.4) 36 (87.8) 7 34 (20.6) 30 (24.2) 4 (9.8) ≥ 8 9 (5.5) 8 (6.4) 1 (2.4) Positive surgical margin .127 .104 No 149 (90.3) 114 (92.0) 35 (85.4) Yes 16 (9.7) 10 (8.0) 6 (14.6) Abbreviations: LRP, laparoscopic radical prostatectomy. Impact of prostate weight on nerve sparing LRP-Jiang et al. nence rates at the 3rd, 6th, and 12th month after surgery were 63.6% (105/165), 87.9% (145/165), and 95.8% (158/165); and the potency rates were 44.8% (74/165), 62.4% (103/165) and 77.6% (128/165), respective- ly. For univariate and multivariate Cox proportional hazards analysis, the first subgroup of each variable has been set as the reference (comparative level). As demonstrated in Tables 3 and 4, both univariate and multivariate Cox analysis indicated that patient age (HR = 0.52, 95% CI: 0.35-0.76, P = .001) and prostate weight (HR = 0.54, 95% CI: 0.34-0.86, P = .009) were independent predictors for continence recovery, while only patient age (HR = 0.66, 95% CI: 0.45-0.96, P = .029) could independently predict potency recovery. Since prostate weight was strongly correlated with pa- tient age in the Spearman correlation coefficient anal- ysis, data were further evaluated by stratified models, aiming to confirm predictive value of prostate weight independent of patient age. We also performed Cox re- gression analysis according to subgroups of patient age (data not shown). The P value for prostate weight in continence recovery prediction in the stratified model was .011, which confirmed that prostate weight was an independent predictor for continence recovery. DISCUSSION Widespread PSA screening, combined with the tech- nical improvement of prostate biopsy, has resulted in increased diagnosis of PCa and detection of lower grade and earlier stage disease. The morbidity and mortality of PCa in China, although not as high as those in the Table 3. Univariate and multivariate analysis of prognostic factors for continence. Variables Univariate Multivariate HR (95%CI) P-value HR (95%CI) P-value Age (< 65 vs. ≥ 65 years) 0.48 (0.34-0.66) < .001 0.52 (0.35-0.76) .001 BMI (< 24 vs. ≥ 24 kg/m2) 1.31 (0.96-1.80) .087 0.73 (0.52-1.02) .063 Preoperative PSA (< 7 vs. 7-10 ng/ml) 0.70 (0.51-0.96) .026 0.83 (0.58-1.19) .310 Prostate weight (< 75 vs. ≥ 75 g) 0.50 (0.34-0.72) < .001 0.54 (0.34-0.86) .009 Clinical T stage (≤ cT1c vs. cT2a) 0.70 (0.50-0.99) .041 0.70 (0.49-1.01) .053 Biopsy Gleason score (< 6 vs. 6) 0.84 (0.56-1.26) .387 0.68 (0.44-1.07) .095 Operative time (< 200 vs. ≥ 200 mins) 0.98 (0.72-1.34) .900 1.20 (0.85-1.69) .295 Estimated blood loss (< 250 vs. ≥ 250 ml) 0.83 (0.61-1.23) .224 0.84 (0.60-1.17) .290 Perioperative complications .105 .181 None 1 (reference) 1 (reference) Clavien I-II 0.70 (0.46-1.08) .109 0.73 (0.46-1.18) .201 Clavien III-IV 0.46 (0.17-1.25) .129 0.44 (0.15-1.30) .135 Pathological T stage .270 .487 pT2a 1 (reference) 1 (reference) pT2b 1.19 (0.83-1.69) .342 1.20 (0.81-1.75) .364 ≥ pT2c 0.79 (0.50-1.24) .304 0.88 (0.51-1.51) .639 Pathological Gleason score .494 .322 < 7 1 (reference) 1 (reference) 7 1.00 (0.68-1.47) .993 1.13 (0.74-1.73) .572 ≥ 8 0.66 (0.34-1.31) .238 0.61 (0.28-1.31) .202 Positive surgical margin (No vs. Yes) 0.53 (0.30-0.94) .029 0.62 (0.34-1.15) .128 Abbreviations: BMI, body-mass index; PSA, prostate-specific antigen; HR, hazard ratio; CI, confidence interval. Variables Univariate Multivariate HR (95%CI) P-value HR (95%CI) P-value Age (< 65 vs. ≥ 65 years) 0.63 (0.46-0.87) .005 0.66 (0.45-0.96) .029 BMI (< 24 vs. ≥ 24 kg/m2) 0.84 (0.61-1.15) .271 0.90 (0.64-1.27) .560 Preoperative PSA (< 7 vs. 7-10 ng/ml) 0.85 (0.62-1.16) .290 1.11 (0.79-1.56) .539 Prostate weight (< 75 vs. ≥ 75 g) 0.89 (0.62-1.28) .528 0.93 (0.58-1.50) .763 Clinical T stage (≤ cT1c vs. cT2a) 0.73 (0.52-1.03) .072 0.79 (0.55-1.15) .224 Biopsy Gleason score (< 6 vs. 6) 0.97 (0.64-1.46) .881 1.04 (0.67-1.62) .854 Operative time (< 200 vs. ≥ 200 mins) 0.72 (0.53-0.99) .004 0.73 (0.52-1.03) .077 Estimated blood loss (< 250 vs. ≥ 250 ml) 1.19 (0.87-1.63) .280 1.22 (0.87-1.72) .251 Perioperative complications .243 .100 None 1 (reference) 1 (reference) Clavien I-II 1.13 (0.74-1.71) .574 1.02 (0.65-1.60) .923 Clavien III-IV 0.40 (0.13-1.27) .121 0.27 (0.08-0.90) .034 Pathological T stage .362 918 pT2a 1 (reference) 1 (reference) pT2b 0.96 (0.68-1.37) .840 0.94 (0.64-1.37) .741 . ≥ pT2c 0.72 (0.45-1.14) .158 0.92 (0.56-1.51) .738 Pathological Gleason score .045 .085 < 7 1 (reference) 1 (reference) 7 1.06 (0.73-1.56) .756 0.92 (0.61-1.41) .707 ≥ 8 0.39 (0.18-0.83) .015 0.39 (0.17-0.90) .026 Positive surgical margin (No vs. Yes) 1.31 (0.75-2.27) .343 1.31 (0.72-2.39) .380 Abbreviations: BMI, body-mass index; PSA, prostate-specific antigen; HR, hazard ratio; CI, confidence interval. Impact of prostate weight on nerve sparing LRP-Jiang et al. Table 4. Univariate and multivariate analysis of prognostic factors for potency. Urological Oncology 263 Vol 16 No 03 May-June 2019 264 western countries, were increasing markedly during the past decade.(20) RP has been established as the most durable treatment option for patients with clinically lo- calized PCa, especially for those with good life expec- tancy. Following the first performance of LRP by Gao et al. in China,(21) this procedure has become a routine treatment modality for localized PCa in large medical centers of the country. Actually, the development of minimally invasive surgical techniques has resulted in greater focus on achieving optimal functional outcomes and QOL in patients after RP. Hence, the effect of var- ious patient characteristics on outcomes of the surgery, especially for younger patients with preoperative po- tency, needs to be assessed comprehensively to provide valuable guidance for surgeons and patients. Although LRP is generally safe in patients with large prostates, removal of larger gland is commonly be- lieved to be more technically challenging.(9-11) The cur- rent study analyzed the impact of prostate weight on outcomes of nerve sparing LRP for treatment of low risk PCa, and assessed the predictive value of prostate weight for postoperative continence and potency recov- ery. To our knowledge, no standard definition of a large prostate has ever been demonstrated, while the prostates of > 75 g versus those < 75 g were reported to be sig- nificantly different in surgical margin status, estimated blood loss and PSA failure-free survival rate.(12,13) Thus we divided the patients into two groups, according to the prostate weight of < 75 g or ≥ 75 g, for the data ana- lyzing in our research. Most series have reported that patients with larger prostates experienced longer oper- ative time, higher intraoperative blood loss, and lower pathological stage than those with smaller prostates, while there is no consistence with regard to the influ- ence of prostate weight on PSM and transfusion rate.(9- 13) In our study series, the PSM rate was 9.7% (16/165), and 84.8% (140/165) of the cases had a pathological T stage of ≤ pT2b, which were both more improved than those presented in the above series. The main reason might be that all cases included in the present research were low risk localized PCa. In addition, our data showed that older patients tend to have lager prostate weight. Actually, it is common that PCa patients have a comorbidity of benign prostatic hyperplasia, which oc- curred in 50% of men 60 years or older and 80% of men 80 years or older,(22) this may explain why older patients were likely to have larger prostate weight in our study. Similarly, we found that increased prostate weight was significantly associated higher PSA level, lower biop- sy and pathological T stage and Gleason score in the low risk PCa cohort. This result is not surprising, the increased PSA production from enlarged adenoma tissue may lead to earlier detection and biopsy in the natural history of PCa, making the diagnosis of com- paratively lower risk tumor. Furthermore, it is easy to understand that increased prostate weight was associat- ed with longer operative time and higher intraoperative blood loss. As the poor visualization caused by a large prostate size makes it more challenging to expose and dissect surrounding tissues of the gland, which might lead to either direct or indirect injuries to blood vessels. The central goal of RP is complete extirpation of the primary tumor, while patients’ QOL could be negative- ly influenced by the presence of urinary incontinence and erectile dysfunction. Therefore, more effective prognostic predictors for continence and potency re- covery after RP are required to provide professional consultation for patients before surgery. In the multi- variate Cox regression analysis, we identified larger prostate weight as an independent predictor for poor continence recovery, which is in line with our previous research(23) conducted in high risk PCa patients. More- over, we found that smaller patient age could predict better continence and potency recovery. This finding is in accordance with the results of the study conducted in 3,477 patients by Kundu SD et al.(24) Urinary incon- tinence and erectile dysfunction after LRP are multi- factorial including neurogenic and vasculogenic inju- ries due to traction, direct transaction, thermal injury or incorporation into haemostatic sutures with clips.(25, 26) The postoperative continence and potency recovery may therefore be compromised, especially in patients with large prostate as the technical challenge during the procedures. In the present study, the continence rates at the 3rd, 6th, and 12th month after surgery were 63.6%, 87.9%, and 95.8%; and the potency rates were 44.8%, 62.4% and 77.6%, respectively. Our results compared favorably with the majority of recently published series of patients treated with nerve sparing RP,(3-5) as we have conducted a precise anatomical intrafascial nerve spar- ing approach during the surgeries. The prostatic fascia, lateral pelvic fascia, and anterior layer of Denonvillier’s fascia fuse with each other posterolateral to the prostate, and form a potential triangular space containing NVB. (27, 28) The intrafascial plane is the plane between the prostate capsule and the prostatic fascia, which could preserve almost all NVB fibers even if they distribute in a more dispersed shape.(3-5) Besides, we have per- formed a retrograde dissection approach in our nerve sparing LRP, as it could identify and release NVB from the prostate before ligation of the prostatic pedicles to avoid traction and potential injuries to NVB by any sub- sequent manipulation of the prostate. The major strengths of the present study include the use of validated questionnaires to assess functional out- comes. Furthermore, all LRPs of the series were per- formed by one single surgeon, maintaining consistency of all surgical techniques. Simultaneously, there are certain limitations in our study. First, the weak point of the present study is inherent in its retrospective nature. In addition, the relatively small number of patients in- cluded is also the shortcoming. However, it’s enough to guarantee statistical significance. CONCLUSIONS In summary, our data suggested that increased prostate weight was significantly associated with older patient age, higher preoperative PSA level, lower tumor stage and grade, longer operative time, and higher intraoper- ative blood loss in patients with low risk PCa. Larger prostate weight might be an independent prognostic predictor for poor continence recovery after nerve spar- ing LRP, and it could be beneficial for patient coun- seling on the functional outcomes after surgery. ACKNOWLEDGEMENTS The authors acknowledge financial support received from the National Natural Science Foundation of Chi- na (81572503, 81772722), the Clinical Medical Re- search and Transformation Centre Projects of Guang- zhou, China (201604020006), and the Science and Technology Planning Project of Guangdong Province Impact of prostate weight on nerve sparing LRP-Jiang et al. (702206453235). CONFLICTS OF INTEREST None declared. REFERENCES 1. Walsh PC. Anatomic radical prostatectomy: evolution of the surgical technique. J Urol. 1998;160:2418-24. 2. Donovan JL, Hamdy FC, Lane JA, et al. Patient-Reported Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer. N Engl J Med. 2016;375:1425-37. 3. 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