[Near-infrared targeted probe designed for intraoperative imaging of prostatic neurovascular bundles]

OBJECTIVE

To investigate the imaging effect of a near-infrared fluorescent targeted probe ICG-NP41 on the neurovascular bundles (NVB) around the prostate in rats.

METHODS

A near-infrared fluorescent targeted probe ICG-NP41 was synthesized. An animal model for NVB imaging was established using Sprague-Dawley rats (250-400 g). Experiments were conducted using a custom-built near-infrared windowⅡ(NIR-Ⅱ) small animal in vivo imaging system, and images collected were processed using ImageJ and Origin. The fluorescence signal data were statistically analyzed using GraphPad Prism. The signal-to-background ratio (SBR) for NVB was quantitatively calculated to explore the effective dosage and imaging time points. Finally, paraffin pathology sections and HE staining were performed on the imaging structures.

RESULTS

Except for rats in the control group (n=2), right-sided NVB of the rats injected with ICG-NP41 (n=2 per group) were all observed in NIR-Ⅱ fluorescence mode 2 h and 4 h after administration. At 2 h and 4 h, average SBR of cavernous nerve in 2 mg/kg group in fluorescence mode was 1.651±0.142 and 1.619±0.110, respectively, both higher than that in white light mode (1.111±0.036), with no significant difference (P>0.05); average SBR of 4 mg/kg group in fluorescence mode were 1.168±0.066 and 1.219±0.118, respectively, both higher than that in white light mode (1.081±0.040), with no significant difference (P>0.05). At 2 h and 4 h, the average SBR of 2 mg/kg and 4 mg/kg groups in fluorescence mode were higher than that of the control group (SBR=1), the average SBR of the 2 mg/kg group was higher than that of the 4 mg/kg group, and all the above with no significant difference (P>0.05). The average diameter of the nerve measured by full width at half maxima method was about (178±15) μm. HE staining of paraffin sections showed the right major pelvic ganglion.

CONCLUSION

The near-infrared fluorescent targeted probe ICG-NP41 can be used for real-time imaging of the NVB around the prostate in rats, providing a potential feasible solution for localizing NVB in real time during nerve-sparing radical prostatectomy.

[Predictive model of early urinary continence recovery based on prostate gland MRI parameters after laparoscopic radical prostatectomy]

OBJECTIVE

Constructing a predictive model for urinary incontinence after laparoscopic radical prostatectomy (LRP) based on prostatic gland related MRI parameters.

METHODS

In this study, 202 cases were included. All the patients were diagnosed with prostate cancer by prostate biopsy and underwent LRP surgery in Peking University Third Hospital. The preoperative MRI examination of all the patients was completed within 1 week before the prostate biopsy. Prostatic gland related parameters included prostate length, width, height, prostatic volume, intravesical prostatic protrusion length (IPPL), prostate apex shape, etc. From the first month after the operation, the recovery of urinary continence was followed up every month, and the recovery of urinary continence was based on the need not to use the urine pad all day long. Logistic multivariate regression analysis was used to analyze the influence of early postoperative recovery of urinary continence. Risk factors were used to draw the receiver operator characteristic (ROC) curves of each model to predict the recovery of postoperative urinary continence, and the difference of the area under the curve (AUC) was compared by DeLong test, and the clinical net benefit of the model was evaluated by decision curve analysis (DCA).

RESULTS

The average age of 202 patients was 69.0 (64.0, 75.5) years, the average prostate specific antigen (PSA) before puncture was 12.12 (7.36, 20.06) μg/L, and the Gleason score < 7 points and ≥ 7 points were 73 cases (36.2%) and 129 cases (63.9%) respectively, with 100 cases (49.5%) at T1/T2 clinical stage, and 102 cases (50.5%) at T3 stage. The prostatic volume measured by preoperative MRI was 35.4 (26.2, 51.1) mL, the ratio of the height to the width was 0.91 (0.77, 1.07), the membranous urethral length (MUL) was 15 (11, 16) mm, and the IPPL was 2 (0, 6) mm. The prostatic apex A-D subtypes were 67 cases (33.2%), 80 cases (39.6%), 24 cases (11.9%) and 31 cases (15.3%), respectively. The training set and validation set were 141 cases and 61 cases, respectively. The operations of all the patients were successfully completed, and the urinary continence rate was 59.4% (120/202) in the 3 months follow-up. The results of multivariate analysis of the training set showed that the MUL (P < 0.001), IPPL (P=0.017) and clinical stage (P=0.022) were independent risk factors for urinary incontinence in the early postoperative period (3 months). The nomogram and clinical decision curve were made according to the results of multivariate analysis. The AUC value of the training set was 0.885 (0.826, 0.944), and the AUC value of the validation set was 0.854 (0.757, 0.950). In the verification set, the Hosmer-Lemeshow goodness-of-fit test was performed on the model, and the Chi-square value was 5.426 (P=0.711).

CONCLUSION

Preoperative MUL, IPPL, and clinical stage are indepen-dent risk factors for incontinence after LRP. The nomogram developed based on the relevant parameters of MRI glands can effectively predict the recovery of early urinary continence after LRP. The results of this study require further large-scale clinical research to confirm.

[Relationship between recovery of urinary continence after laparoscopic radical prostatectomy and preoperative/postoperative membranous urethral length]

OBJECTIVE

To evaluate the relationship between recovery of urinary continence after laparoscopic radical prostatectomy (LRP) and preoperative/postoperative membranous urethral length (MUL) on magnetic resonance imaging.

METHODS

We retrospectively analyzed 69 patients with pathologic confirmed prostate carcinoma who underwent laparoscopic radical prostatectomy. Preoperative MUL was defined as the distance from the apex of prostate to the level of the urethra at penile bulb on the coronal image. Postoperative MUL was defined as the distance from the bladder neck to the level of the urethra at the penile bulb on the coronal image. MUL-retained rate was defined as the percentage of postoperative MUL to preoperative MUL. All patients received extraperitoneal LRP. Patients reported freedom from using safety pad (0 pad/d) were defined as urinary continence. Multivariate Logistic regression analyses were used to identify independent predictors of early continence recovery after LRP. Kaplan-Meier analyses and log-rank test were used to compare time to continence recovery between the groups.

RESULTS

For all the 69 patients, the average age was (71.4±8.6) years. The prostate specific antigen before biopsy was (23.40±30.31) μg/L, and the mean preoperative prostatic volume by magnetic resonance imaging was (39.48±22.73) mL. The mean preoperative MUL was (13.0±3.3) mm, the mean postoperative MUL was (12.3±3.4) mm, and the mean MUL-retained rate was 93.9%±6.2%. The continence rate for all the patients after LRP was 57.9% and 97.1% in three months and one year, respectively. The patients achieving early continence recovery had significant smaller prostatic volume (P=0.028), longer preoperative MUL and postoperative MUL (P < 0.001). Multivariate Logistic regression analyses revealed postoperative MUL (P < 0.001) were predictors of continence recovery after LRP. Kaplan-Meier analyses and Log-rank test revealed that preoperative MUL (≥14 mm vs. < 14 mm, P < 0.001) and postoperative MUL (≥13 mm vs. < 13 mm, P < 0.001), MUL-retained rate (< 94% vs. ≥94%, P < 0.001) were all significantly associated with continence recovery.

CONCLUSION

Post-operative MUL was independently predictors of early continence recovery after LRP. Preoperative MUL, postoperative MUL and MUL retained rate were significantly associated with recovery of urinary continence.

[Surgical strategy selection and experience summary of prostate cancer with positive single needle biopsy]

OBJECTIVE

To analyze the clinicopathological characteristics of prostate cancer patients undertaking radical prostatectomy with single positive core biopsy, and to optimize the rational choice of therapeutic strategy.

METHODS

In the study, 53 patients with single positive core prostate biopsy and treated by radical prostatectomy from January 2010 to December 2018, were analyzed retrospectively. The mean age was (69.7±6.9) years (54-81 years), the mean prostate specific antigen (PSA) level was (9.70±5.24) μg/L (1.69-25.69 μg/L), and the mean prostate volume was (50.70±28.39) mL (12.41-171.92 mL). Thirty-nine out of 54 (73.6%) patients presented Gleason score with 6, 11 patients (20.8%) had Gleason score of 7 and 3 patients (5.7%) showed Gleason score ≥8. For clinical stages, 6 out of the 53 patients (11.3%) had prostate cancer in cT1, 44 cases (83.0%) had prostate cancer in cT2, and 3 cases (5.7%) in cT3.The patients were divided into subgroups according to age, preoperative PSA level, Gleason score, percentage of tumor in single needle tissue and clinical stage, and the differences of their clinicopathological characteristics were compared.

RESULTS

Postoperative Gleason score of 6, 7 and ≥8 were found in 20 cases (37.7%), 21 cases (39.6%) and 10 cases (18.9%) respectively, another 2 cases (3.8%) were pT0 prostate cancer; pathological stages of T0, T2a, T2b, T2c and T3 were found in 2 cases (3.8%), 9 cases (17.0%), 2 cases (3.8%), 29 cases (54.7%) and 11 cases (20.8%) respectively; 11 cases (20.8%) had positive surgical margin, 10 cases (18.9%) had extracapsular invasion of prostate, and 1 case (1.9%) showed seminal vesicle invasion. Forty-two cases (79.2%) had multifocal lesions and 37 cases (69.8%) presented bilateral lesion. Compared with the biopsy Gleason score, the postoperative Gleason score was downgrated in 3 cases (5.7%), unchanged in 28 cases (52.8%), and upgraded in 20 cases (37.7%), of which 2 cases (3.8%) were pT0. Compared with the clinical stage, the postoperative pathological stage decreased in 2 cases (3.8%), unchanged in 10 cases (18.9%), and upgraded in 41 cases (77.4%). According to the postoperative pathology, the patients were divided into two groups: microfocus cancer group (n=8) and non-microfocus cancer group (n=45). The difference between the two groups in the percentage of tumor in the single-needle tissue ≤5% was statistically significant (P=0.014). Other parameter diffe-rences including age, prostate volume, and preoperative prostate special antigen density (PSAD) and Gleason scores were not statistically significant (P>0.05). The method to determine the location of cancer at the apex of prostate according to biopsy results showed 41.4% (12/29) false negative rate and 50.0% (12/24) false positive rate. There was statistically significant difference between the actual cases of lymph node dissection and reserved nerve and the cases of scheme selection in theory according to the postoperative pathology (P < 0.05).

CONCLUSION

The proportion of single needle cancer tissue less than or equal to 5% is a predictor of prostate microfocal cancer. 37.7% cases had pathological upgrading and 77.4% cases had pathological staging upgrading. When choosing the operation scheme, such as sexual nerve reserved, lymph node dissection and apex operation skill, it is necessary to comprehensively analyze multiple factors, such as tumor risk classification, prediction factors of nomogram, multi-parameter MRI and intraoperative situation and so on.

[Surgical strategy selection and experience summary of prostate cancer with positive single needle biopsy]

OBJECTIVE

To analyze the clinicopathological characteristics of prostate cancer patients undertaking radical prostatectomy with single positive core biopsy, and to optimize the rational choice of therapeutic strategy.

METHODS

In the study, 53 patients with single positive core prostate biopsy and treated by radical prostatectomy from January 2010 to December 2018, were analyzed retrospectively. The mean age was (69.7±6.9) years (54-81 years), the mean prostate specific antigen (PSA) level was (9.70±5.24) μg/L (1.69-25.69 μg/L), and the mean prostate volume was (50.70±28.39) mL (12.41-171.92 mL). Thirty-nine out of 54 (73.6%) patients presented Gleason score with 6, 11 patients (20.8%) had Gleason score of 7 and 3 patients (5.7%) showed Gleason score ≥8. For clinical stages, 6 out of the 53 patients (11.3%) had prostate cancer in cT1, 44 cases (83.0%) had prostate cancer in cT2, and 3 cases (5.7%) in cT3.The patients were divided into subgroups according to age, preoperative PSA level, Gleason score, percentage of tumor in single needle tissue and clinical stage, and the differences of their clinicopathological characteristics were compared.

RESULTS

Postoperative Gleason score of 6, 7 and ≥8 were found in 20 cases (37.7%), 21 cases (39.6%) and 10 cases (18.9%) respectively, another 2 cases (3.8%) were pT0 prostate cancer; pathological stages of T0, T2a, T2b, T2c and T3 were found in 2 cases (3.8%), 9 cases (17.0%), 2 cases (3.8%), 29 cases (54.7%) and 11 cases (20.8%) respectively; 11 cases (20.8%) had positive surgical margin, 10 cases (18.9%) had extracapsular invasion of prostate, and 1 case (1.9%) showed seminal vesicle invasion. Forty-two cases (79.2%) had multifocal lesions and 37 cases (69.8%) presented bilateral lesion. Compared with the biopsy Gleason score, the postoperative Gleason score was downgrated in 3 cases (5.7%), unchanged in 28 cases (52.8%), and upgraded in 20 cases (37.7%), of which 2 cases (3.8%) were pT0. Compared with the clinical stage, the postoperative pathological stage decreased in 2 cases (3.8%), unchanged in 10 cases (18.9%), and upgraded in 41 cases (77.4%). According to the postoperative pathology, the patients were divided into two groups: microfocus cancer group (n=8) and non-microfocus cancer group (n=45). The difference between the two groups in the percentage of tumor in the single-needle tissue ≤5% was statistically significant (P=0.014). Other parameter diffe-rences including age, prostate volume, and preoperative prostate special antigen density (PSAD) and Gleason scores were not statistically significant (P>0.05). The method to determine the location of cancer at the apex of prostate according to biopsy results showed 41.4% (12/29) false negative rate and 50.0% (12/24) false positive rate. There was statistically significant difference between the actual cases of lymph node dissection and reserved nerve and the cases of scheme selection in theory according to the postoperative pathology (P < 0.05).

CONCLUSION

The proportion of single needle cancer tissue less than or equal to 5% is a predictor of prostate microfocal cancer. 37.7% cases had pathological upgrading and 77.4% cases had pathological staging upgrading. When choosing the operation scheme, such as sexual nerve reserved, lymph node dissection and apex operation skill, it is necessary to comprehensively analyze multiple factors, such as tumor risk classification, prediction factors of nomogram, multi-parameter MRI and intraoperative situation and so on.