[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.

[Application of intraoperative CT-assisted positioning in difficult cases of cochlear implantation]

Objective:To report the experience of using CT-guided cochlear implant surgery in difficult cases such as severe inner ear deformities and anatomical abnormalities, and to discuss the application value of intraoperative CT-assisted localization in difficult cases of cochlear implant surgery. Methods:Retrospectively analyzed the clinical data of 23 cases of difficult cochlear implant surgery cases completed by our team with the assistance of intraoperative CT, and collected their medical data, including preoperative imaging manifestations, surgical conditions, and intraoperative imaging images for evaluation. Results:During the study period, 23 difficult cases（27 ears） underwent cochlear implantation under the guidance of intraoperative CT, and 4 cases were bilaterally implanted. Including 6 cases of incomplete segmentation type Ⅰ（IP-Ⅰ）, 1 case of incomplete segmentation type Ⅱ（IP-Ⅱ）, 10 cases of incomplete segmentation type Ⅲ（IP-Ⅲ）, 3 cases of common cavity deformity（CC） and 3 cases of cochlear ossification after meningitis. Facial nerve anatomy was abnormal in 9 cases, cerebrospinal fluid "blowout" was serious in 14 cases, electrode position was abnormal in 3 cases requiring intraoperative adjustment of electrode position, anatomical difficulties required intraoperative CT to assist in finding anatomical landmarks in 2 cases, and electrodes were not fully implanted in 3 cases. Conclusion:When faced with difficult cases with challenging and complex temporal bone anatomy, intraoperative CT can accurately evaluate the electrode position and provide intraoperative anatomical details, allowing immediate adjustment of the electrode position if necessary, providing safety guarantee for difficult cases of cochlear implant surgery and ensure accurate implantation of electrodes.

[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.

[Individual control of urine volume to improve stability of bladder volume in radiotherapy of urinary tumor]

OBJECTIVE

To explore the training mode of individual urine volume control, to take indi-vidual expected urine volume as the goal of bladder control in patients with urinary system tumors, and to improve the accuracy of bladder control during radiotherapy by active training of bladder receptivity.

METHODS

Twenty-five patients of urinary system tumors were enrolled from May 2019 to September 2019, of whom, 21 patients had prostate cancer, and 4 had bladder cancer. Training of bladder filling started before CT simulation. The patients were required to take the individual bladder filling as the training goal, and the optimal bladder volume range was suggested to be 200－400 mL. After 2－4 weeks of training, the prescribed volume of the bladder was determined according to the patient's bladder receptivity. The volume of the bladder was measured by images of plain CT and images 8-minutes after intravenous contrast injection. The patient's bladder volume was measured using BladderScan before treatment. CBCT (Cone-beam CT) was performed, and bladder volume was measured before treatment. The bladder volume was measured again using BladderScan after treatment.

RESULTS

The mean bladder volume of simulation (V_CT01) was (262±130) mL, ranging from 78 mL to 505 mL. The mean self-evaluation bladder volume before radiotherapy (V_EVA01) was (238±107) mL, ranging from 100 mL to 400 mL. The mean BladderScan measured volume before radiotherapy (V_BVI01) was (253±123) mL, ranging from 60 mL to 476 mL. The mean cone-beam CT measured volume before radiotherapy (V_CBCT) was (270±120) mL, ranging from 104 mL to 513 mL. There was a correlation between V_EVA01 and V_BVI01, V_CT01 and V_BVI01, V_CT01, and V_BVI01, and there was no significant difference in paired t-test. There was a correlation between differences of self-evaluation bladder volume before radiotherapy(V_EVA01) and simulation CT (V_CT01) and differences of self-evaluation bladder volume before radiotherapy (V_EVA01) and cone-beam CT (V_CBCT), and there was no significant difference in paired samples by t-test.

CONCLUSION

During radiotherapy for urinary system tumors, such as prostate cancer and bladder cancer, with the assistance of BladderScan, the patients could try to hold their urine moderately according to their conditions, and individualized bladder prescription may be beneficial to achieve stable bladder volume during radiotherapy.

[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.

[Low power seven-step two-lobe holmium laser enucleation of the prostate technique for surgical treatment of benign prostatic hyperplasia]

OBJECTIVE

To evaluate the safety and efficacy of the seven-step two-lobe holmium laser enucleation of the prostate (HoLEP) technique with low power laser device, and to introduce the detailed operating procedures, key points, short-term outcomes of this modified HoLEP technique.

METHODS

From March 2016 to November 2017, 90 patients underwent HoLEP in Peking University Third Hospital. The patients were divided into two groups: high-power group (32 patients) were performed with traditional Gilling's three-lobe enucleation using high power (90 W) laser; Low-power group (58 patients) were performed with seven-step two-lobe enucleation using low power (40 W) laser. The main steps of the low power seven-step two-lobe HoLEP phase included: (1) The identification of the correct plane between adenoma and capsule at 5 and 7 o'clock laterally to the veru montanum; (2) The connection of the bilateral plane by making a adenoma incision at the proximal point of veru montanum; (3) The extension of the dorsal plane under the whole three lobes between adenoma and capsule towards the bladder neck; (4) The separation of the middle lobe from two lateral lobes by making two retrograde incisions separately from apex 5 and 7 o'clock towards the bladder neck; (5) The enucleation of the middle lobe adenoma by extending the dorsal plane through into the bladder; (6) The prevention of the apex mucosa by making a circle incision at the apex of the prostate; (7) The en-bloc enucleation of the two lateral lobe adenomas by extending the lateral and ventral plane between adenoma and capsule from 5 and 7 o'clock to 12 o'clock conjunction and through into the bladder.

RESULTS

The mean patient age was (66.25±5.37) years vs. (68.00±5.18) years; The mean body mass indexes were (24.13±4.06) kg/m² vs. (24.57±3.50) kg/m²; The mean prostate specific antigen values were (3.23±2.47) μg/L vs. (6.00±6.09) μg/L; The average prostatic volumes evaluated by ultrasound was (49.03±20.63) mL vs. (67.55±36.97) mL. There was no significant difference between the two groups. Furthermore, there were no significant differences in terms of perioperative and follow up data, including operative time; enucleation efficiencies; hemoglobin decrease; blood sodium and potassiumthe change postoperatively; catheterization duration and hospital stay; the international prostate symptom scores and quality of life scores pre- and post-operatively. There was 1 transurethral resection of the prostate (TURP) conversion in high-power group and 1 transfusion in low-power group during the operations. The follow-up one month after operation showed no severe stress incontinence in both the groups, whereas 3 cases ejaculatory dysfunctions in high-power group versus 1 case in low-power group were observed; Other surgeryrelated complications included: 2 cases postoperative hemorrhage (Clavien II and Clavien IIIb) in high-power group, 2 cases postoperative temperature more than 38 °C (Clavien I) and 1 case dysuria following catheter removal (Clavien I) in low-power group.

CONCLUSION

Low power laser device can be applied safe and effectively for HoLEP procedure using the seven-step two-lobe HoLEP technique. The outcomes comparable with high power laser HoLEP can be achieved.

[Rasfonin inhibits proliferation and migration of osteosarcoma 143B cells]

OBJECTIVE

To investigate the effects of rasfonin, a fungal secondary metabolite, on the proliferation and migration of osteosarcoma 143B cells.

METHODS

3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay was performed to examine 143B cell viability following treatment of rasfonin. Using dimethyl sulfoxide (DMSO) group as control, cell viability was detected when 143B cells were treated with rasfonin (3 μmol/L and 6 μmol/L) for 12 or 24 hours. The effect of rasfonin on colony forming ability was detected by clone formation assay. 143B cells treated with DMSO or rasfonin (3 μmol/L) for one week, and the number of clones formed in the two groups was counted. Wound healing and transwell assay were employed to analyze cell invasion and migration upon rasfonin challenge. The DMSO group was used as control while rasfonin (3 μmol/L) was used for 24 hours. The wound healing rate and the number of invasive cells were compared between the two groups. The intracellular autophagosomes were monitored by transmission electron microscopy when 143B cells were treated with DMSO or rasfonin (3 μmol/L) for 4 hours. The expression of p62, microtubule-associated protein 1 light chain 3 fusion protein (LC3) and poly (ADP-ribose) polymerase-1 (PARP-1) in response to rasfonin were detected by immunoblotting assay.

RESULTS

Rasfonin reduced the viability of 143B cells in a dose-dependent manner (12 h: F=31.36, P<0.01; 24 h: F=67.07, P<0.01). Rasfonin (3 μmol/L) completely inhibited the clonal formation of 143B cells (P<0.01). The wound healing result revealed that rasfonin significantly decreased migratory ability of 143B cells (33.91%±0.83% vs. 65.11%±0.94%, P<0.01), whereas its treatment significantly reduced the number of 143B cells penetrating through Matrigel-containing basement membrane (21.33±1.45 vs. 49.33±2.40, P<0.01). Compared with the control group, rasfonin markedly increased the number of autophagic vacuoles. The immunoblotting results revealed that rasfonin increased LC3-II accumulation and decreased p62 levels. Choloroquine (CQ), an often used autophagic inhibitor, further accumulated rasfonin-induced LC3-II. In addition, rasfonin appeared to cause the cleavage of PARP-1.

CONCLUSION

Rasfonin induced autophagy and activated caspase-dependent apoptosis in 143B cells concurring with suppressing the proliferation and migration of the cells; these results provide an experimental basis for rasfonin as a potential therapeutic agent for osteosarcoma.

[Mechanism of heat shock protein 90 for regulating 26S proteasome in hyperthermia]

OBJECTIVE

To investigate the mechanism by which heat shock protein 90 (HSP90) regulates 26S proteasome in hyperthermia.

METHODS

Hyperthermic HepG2 cell models established by exposure of the cells to 42 degrees celsius; for 3, 6, 12, and 24 h were examined for production of reactive oxygen species (ROS) and cell proliferation, and the changes in Hsp90α and 26S proteasome were analyzed.

RESULTS

ROS production in the cells increased significantly after hyperthermia (F=28.958, P<0.001), and the cell proliferation was suppressed progressively as the heat exposure time extended (F=621.704, P<0.001). Hyperthermia up-regulated Hsp90α but decreased the expression level (F=164.174, P<0.001) and activity (F=133.043, P<0.001) of 26S proteasome. The cells transfected with a small interfering RNA targeting Hsp90α also showed significantly decreased expression of 26S proteasome (F=180.231, P<0.001).

CONCLUSION

The intracellular ROS production increases as the hyperthermia time extends. Heat stress and ROS together cause protein denature, leading to increased HSP90 consumption and further to HSP90 deficiency for maintaining 26S proteasome assembly and stability. The accumulation of denatured protein causes unfolded protein reaction in the cells to eventually result in cell death.