Diagnostic capability of 18F-PSMA PET-MRI and pelvic MRI plus bone scan in treatment-naive prostate cancer: a single-center paired validating confirmatory study.

BACKGROUND: Radical prostatectomy with pelvic lymph node dissection for the treatment of high-risk localized prostate cancer (PCa) results in long-term benefits in selected patients. But insufficient sensitivity of conventional examinations which are pelvic MRI and bone scan, limits the diagnosis of bone and lymph node metastasis of PCa. This affects the surgical management strategy of a large number of patients. The purpose of this study was to investigate whether 18F-prostate-specific membrane antigen (PSMA) PET-MRI could improve the clinical detection of PCa metastases compared with the conventional pelvic MRI plus bone scan. MATERIALS AND METHODS: From April 2020 to April 2023, we prospectively enroled 472 patients with histologically proven PCa in our centre, and 120 patients underwent 18F-PSMA PET-MRI, multiparametric MRI, and bone scan before laparoscopic radical prostatectomy plus lymph node dissection. The accuracy of imaging results in detecting lymph node and bone metastatic lesions was compared between PSMA PET-MRI and MRI plus bone scan. RESULTS: In diagnosing lymph node metastasis, PSMA PET-MRI had an area under the curve (AUC) of 0.844 (95% CI: 0.738-0.949, P < 0.001), sensitivity and specificity of 75% and 96%, which performed apparently better than MRI [AUC=0.615 (95% CI: 0.480-0.750, P =0.073)]. PSMA PET-MRI showed excellent expression in the diagnosis of bone metastases, with an AUC of 0.910 (95% CI: 0.840-0.981, P <0.001) compared to 0.700 (95% CI: 0.577-0.823, P =0.001) in bone scanning. PSMA PET-MRI also had higher sensitivity than bone scanning (90% vs. 43%), while lower specificity (92% vs. 97%). CONCLUSION: PSMA PET-MRI is superior to conventional imaging at diagnosing metastases in lymph nodes and bones in PCa and can provide a more accurate stagement.

Association of biopsy core number and location with pain in patients undergoing a transperineal prostate biopsy under local anaesthesia: a secondary analysis of the APROPOS trial.

BACKGROUND: APROPOS was a multicentre, randomized, blinded trial focus on investigating the perineal nerve block versus the periprostatic block in pain control for men undergoing a transperineal prostate biopsy. In the analysis reported here, the authors aimed to evaluate the association of biopsy core count and location with pain outcomes in patients undergoing a transperineal prostate biopsy under local anesthesia. METHODS: APROPOS was performed at six medical centers in China. Patients with suspected prostate cancer were randomized to receive either a perineal nerve block or a periprostatic block (1:1), followed by a transperineal prostate biopsy. The secondary analysis outcomes were the worst pain experienced during the prostate biopsy and postbiopsy pain at 1,6, and 24 h. RESULTS: Between 12 August 2020 and 20 July 2022, a total of 192 patients were randomized in the original trial, and 188 were involved in this analysis, with 94 patients per group. Participants had a median (IQR) age of 68 (63-72) and a median (IQR) prostate volume of 42.51 (30.04-62.84). The patient population had a median (IQR) number of biopsy cores of 15 (12-17.50), and 26.06% of patients had a biopsy cores count of more than 15. After adjusting the baseline characteristics, the number of biopsy cores was associated with the worst pain during the biopsy procedure in both the perineal nerve block group ( ß 0.19, 95% CI: 0.12-0.26, P <0.001) and the periprostatic block group ( ß 0.16, 95% CI: 0.07-0.24, P <0.001). A similar association was also evident for the postbiopsy pain at 1, 6, and 24 h. A lesser degree of pain in both groups at any time (r range -0.57 to -0.01 for both groups) was associated with biopsy cores from the peripheral zone of the middle gland, while other locations were associated with a higher degree of pain. In addition, the location of the biopsy core had less of an effect on pain during the biopsy (r range -0.01-0.25 for both groups) than it did on postbiopsy pain (r range -0.57-0.60 for both groups). CONCLUSIONS: In this secondary analysis of a randomized trial, biopsy core count and location were associated with pain in patients undergoing a transperineal prostate biopsy under local anesthesia. These results may be helpful for making clinical decisions about the anesthetic approach for scheduled transperineal prostate biopsies.

Efficient 3D scanning measurement system based on asymmetric trinocular vision and a multi-line laser.

The laser scanning measurement system has a pivotal role in precision measurement thanks to the non-contacting and low-cost advantages, but traditional methods and systems are inadequate in terms of accuracy, efficiency, and adaptability. In this study, an efficient 3D scanning measurement system based on asymmetric trinocular vision and a multi-line laser is developed to improve the measurement performance. The system design, working principle, and 3D reconstruction method are explored, as well as the innovation of the developed system. Furthermore, an efficient multi-line laser fringes indexing method is presented based on K-means ++ clustering and hierarchical processing to improve processing speed with guaranteed accuracy, which is the key point of the 3D reconstruction method. Various experiments are conducted to verify the capability of the developed system, and the results show that the developed system fulfills measurement needs in adaptability, accuracy, effectiveness, and robustness. The developed system achieves better results than commercial probes for complex measurement conditions, and measurement precision can be achieved to within 18 µm.

Perineal nerve block versus periprostatic block for patients undergoing transperineal prostate biopsy (APROPOS): a prospective, multicentre, randomised controlled study.

Background: We aimed to investigate perineal nerve block versus periprostatic block in pain control for men undergoing a transperineal prostate biopsy. Methods: In this prospective, randomised, blinded and parallel-group trial, men in six Chinese hospitals with suspected prostate cancer were randomly assigned (1:1) at the point of local anaesthesia to receive a perineal nerve block or periprostatic block and followed by a transperineal prostate biopsy. Centres used their usual biopsy procedure. Operators who performed anaesthesia were trained in both techniques before the trial and were masked to the randomised allocation until the time of anaesthesia and were not involved in the subsequent biopsy procedure and any assessment or analysis. Other investigators and the patients were masked until trial completion. The primary outcome was the level of the worst pain experienced during the prostate biopsy procedure. Secondary outcomes included pain (post-biopsy at 1, 6 and 24 h), changes in blood pressure, heart rate and breathing rate during the biopsy procedure, external manifestations of pain during biopsy, anaesthesia satisfaction, the detection rate of PCa and clinically significant PCa. This trial is registered on ClinicalTrials.gov, NCT04501055. Findings: Between August 13, 2020, and July 20, 2022, 192 men were randomly assigned to perineal nerve block or periprostatic block, 96 per study group. Perineal nerve block was superior for the relief of pain during the biopsy procedure (mean 2.80 for perineal nerve block and 3.98 for periprostatic block; adjusted difference in means -1.17, P < 0.001). Although the perineal nerve block had a lower mean pain score at 1 h post-biopsy compared with the periprostatic block (0.23 vs 0.43, P = 0.042), they were equivalent at 6 h (0.16 vs 0.25, P = 0.389) and 24 h (0.10 vs 0.26, P = 0.184) respectively. For the change in vital signs during biopsy procedure, perineal nerve block was significantly superior to periprostatic block in terms of maximum value of systolic blood pressure, maximum value of mean arterial pressure and maximum value of heart rate. There are no statistical differences in average value of systolic blood pressure, average value of mean, average value of heart rate, diastolic blood pressure and breathing rate. Perineal nerve block was also superior to periprostatic block in external manifestations of pain (1.88 vs 3.00, P < 0.001) and anaesthesia satisfaction (8.93 vs 11.90, P < 0.001). Equivalence was shown for the detection rate of PCa (31.25% for perineal nerve block and 29.17% for periprostatic block, P = 0.753) or csPCa (23.96% for perineal nerve block and 20.83% for periprostatic block, P = 0.604). 33 (34.8%) of 96 patients in the perineal nerve block group and 40 (41.67%) of 96 patients in the periprostatic block group had at least one complication. Interpretation: Perineal nerve block was superior to periprostatic block in pain control for men undergoing a transperineal prostate biopsy. Funding: Grant 2019YFC0119100 from the National Key Research and Development Program of China.

Gross tumor volume delineation in primary prostate cancer on 18F-PSMA-1007 PET/MRI and 68Ga-PSMA-11 PET/MRI.

BACKGROUND: We aimed to assess the clinical value of 18F-PSMA-1007 and 68Ga-PSMA-11 PET/MRI in the gross tumor volume (GTV) delineation of radiotherapy for prostate cancer (PCa). METHODS: Sixty-nine patients were retrospectively enrolled (57 in the 18F subgroup and 12 in the 68Ga subgroup). Three physicians delineated the GTV and tumor length by the visual method and threshold method with thresholds of 30%, 40%, 50%, and 60% SUVmax. The volume correlation and differences in GTVs were assessed. The dice similarity coefficient (DSC) was applied to estimate the spatial overlap between GTVs. For 51 patients undergoing radical prostatectomy, the tumor length (Lpath) of the maximum area was measured, and compared with the longest tumor length obtained based on the images (LMRI, LPET/MRI, LPET, LPET30%, LPET40%, LPET50%, LPET60%) to determine the best delineation method. RESULTS: In the 18F subgroup, (1) GTV-PET/MRI (p < 0.001) was significantly different from the reference GTV-MRI. DSC between them was > 0.7. (2) GTV-MRI (R2 = 0.462, p < 0.05) was the influencing factor of DSC. In the 68Ga subgroup, (1) GTV-PET/MRI (p < 0.05) was significantly different from the reference GTV-MRI. DSC between them was > 0.7. (2) There was a significant correlation between GTV-MRI (r = 0.580, p < 0.05) and DSC. The longest tumor length measured by PET/MRI was in good agreement with that measured by histopathological analysis in both subgroups. CONCLUSION: It is feasible to visually delineate GTV on PSMA PET/MRI in PCa radiotherapy, and we emphasize the utility of PET/MRI fusion images in GTV delineation. In addition, the overlap degree was the highest between GTV-MRI and GTV-PET/MRI, and it increased with increasing volume.

A Multicenter Single-Arm Objective Performance Criteria Trial to Determine the Efficacy and Safety of High-Frequency Irreversible Electroporation as Primary Treatment for Localized Prostate Cancer: A Study Protocol.

INTRODUCTION: The classical pathway for the therapy of low- to intermediate-risk localized prostate cancer is radical prostatectomy or radiation therapy, which has shown a high incidence of complications, including erectile dysfunction, urinary incontinence, and bowel injury. An alternative pathway is to perform an ablation by some energy to the localized lesion, known as focal therapy. High-frequency irreversible electroporation (H-FIRE) is nonthermal energy that can be used in cancer ablation to deliver pulsed high-voltage but low-energy electric current to the cell membrane and to invoke cell death. An H-FIRE pathway has been reported to be tissue-selective, which leads to fewer side effects. METHODS AND ANALYSIS: This is a multicenter and single-arm objective performance criteria (OPC) study, in which all men with localized prostate cancer are allocated to H-FIRE ablation. This trial will assess the efficacy and safety of the H-FIRE ablation for prostate cancer. Efficacy will be assessed by prostate biopsy 6 months after treatment while safety will be assessed by adverse event reports and questionnaires. The main inclusion criteria are moderate to low-risk prostate cancer in NCCN risk classification and had no previous therapy for prostate cancer. A sample size of 110 participants is required. The primary objective is to determine whether the detection rate of clinically significant cancer by prostate biopsy is less than 20% after the H-FIRE ablation. ETHICS AND DISSEMINATION: This study has obtained ethical approval by the ethics committee of all participating centers. The results of the study will be submitted for dissemination and publication in peer-reviewed journals. CONCLUSIONS: This multicenter single-arm objective performance criteria trial will evaluate the efficacy and safety of the use of high-frequency irreversible electroporation in treating prostate cancer. STRENGTHS AND LIMITATIONS OF THIS STUDY: A comprehensive evaluation of imaging and histopathology is used to determine the effect of treatment. Questionnaires were used to assess the treatment side effects. Multicenter and pragmatic designs capacitate higher generalizability. A limitation of this trial is that the prostate biopsy as an endpoint may not be as accurate as of the specimen from prostate prostatectomy. Another limitation is the 6-month follow-up time, making this trial challenging to come to firm conclusions regarding the efficacy and safety of IRE in the long term. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT03838432.

Characterization of the Pore Structure and Fluid Movability of Coal-Measure Sedimentary Rocks by Nuclear Magnetic Resonance (NMR).

Analyzing and mastering the pore structure and fluid movability characteristics of coal-measure sedimentary rocks is significant for the safe and effective development of unconventional resources. In this work, nuclear magnetic resonance (NMR) experiments were carried out on three common fine sedimentary rocks (i.e., shale, mudstone, and sandstone) from a coal-measure stratum in northern China. NMR transverse (T 2) of the water-saturated and centrifuged rock samples are compared and analyzed. Moreover, the pore size distribution (PSD) and the free-fluid volume index (FFI) of the investigated samples are discussed. Results have shown that the shale and mudstone samples are mainly dominated by adsorption pores with a diameter of 0.01-1 µm, while the sandstone samples are dominated by seepage pores with a diameter of 1-100 µm. The FFI results calculated by the cutoff and the area methods are 11.15-77.62 and 7.56-75.96%, respectively. There are good correlations between FFI and porosity, permeability, and reservoir quality index (RQI). Also, the effects on FFI are different on various kinds of clay minerals. The contents of illite and chlorite are negatively correlated with FFI, while kaolinite is positively correlated with FFI.

Robust and accurate sub-pixel extraction method of laser stripes in complex circumstances.

Line laser scanning measurement is a major area of interest within the field of 3D laser scanning measurement. Traditionally, sub-pixel extraction of laser stripes is a dominant point for line laser scanning measurement. In particular, the noise separation of laser stripe images and the accuracy of feature extraction of the laser stripe are the main challenges for sub-pixel extraction of laser stripes in complex circumstances. To this end, this study utilizes a robust and accurate method with two steps to extract sub-pixel features of laser stripes for 3D laser scanning measurement. Laser stripe segmentation based on a deep semantic segmentation network is initially implemented for noise elimination of images. Then, the sub-pixel extraction of the gray peak points of laser stripes is accomplished by Shepard sub-pixel interpolation and gray surface fitting, which can adequately utilize the gray distribution of laser stripes and obtain high-precision and anti-interference results. The robustness, effectiveness, and accuracy are verified by comparative experiments with classical methods. The results indicate that the proposed method can obtain much more complete, denser, and smoother results than traditional methods, especially in challenging measurement conditions, such as a large curved surface, a highly reflective surface, or intense ambient light. The accuracy of the proposed method can meet the requirements of high-precision measurement.