Prostate cancer volume estimations based on transrectal ultrasonography-guided biopsy in order to predict clinically significant prostate cancer

Sialic acid blockade inhibits the metastatic spread of prostate cancer to bone

BACKGROUND

Bone metastasis is a common consequence of advanced prostate cancer. Bisphosphonates can be used to manage symptoms, but there are currently no curative treatments available. Altered tumour cell glycosylation is a hallmark of cancer and is an important driver of a malignant phenotype. In prostate cancer, the sialyltransferase ST6GAL1 is upregulated, and studies show ST6GAL1-mediated aberrant sialylation of N-glycans promotes prostate tumour growth and disease progression.

METHODS

Here, we monitor ST6GAL1 in tumour and serum samples from men with aggressive prostate cancer and using in vitro and in vivo models we investigate the role of ST6GAL1 in prostate cancer bone metastasis.

FINDINGS

ST6GAL1 is upregulated in patients with prostate cancer with tumours that have spread to the bone and can promote prostate cancer bone metastasis in vivo. The mechanisms involved are multi-faceted and involve modification of the pre-metastatic niche towards bone resorption to promote the vicious cycle, promoting the development of M2 like macrophages, and the regulation of immunosuppressive sialoglycans. Furthermore, using syngeneic mouse models, we show that inhibiting sialylation can block the spread of prostate tumours to bone.

INTERPRETATION

Our study identifies an important role for ST6GAL1 and α2-6 sialylated N-glycans in prostate cancer bone metastasis, provides proof-of-concept data to show that inhibiting sialylation can suppress the spread of prostate tumours to bone, and highlights sialic acid blockade as an exciting new strategy to develop new therapies for patients with advanced prostate cancer.

FUNDING

Prostate Cancer Research and the Mark Foundation For Cancer Research, the Medical Research Council and Prostate Cancer UK.

The application of a targeted periprostatic nerve block in transperineal template-guided prostate biopsies

Background

Our study aims to evaluate the anesthetic efficacy of multiparametric magnetic resonance imaging/transrectal ultrasound (mpMRI/TRUS) fusion-guided targeted periprostatic nerve block (PNB) for transperineal template-guided prostate biopsy (TTPB).

Methods

The patients who underwent mpMRI/TRUS fusion-guided prostate biopsy from May 2018 to March 2019 were randomized into two groups using a random number table. The intervention group (n=47) and the control group (n=45) received targeted PNB and traditional PNB, respectively. Visual analog scale (VAS) and visual numeric scale (VNS) scores were used to assess the patients' pain and quantify their satisfaction.

Results

The total detection rate for prostate cancer was 45.7%, with a comparable positive rate between the intervention group (42.6%) and the control group (48.9%), which meant there was no significant difference between the groups (P=0.542). Patient age, prostate-specific antigen, prostate volume, suspicious lesions on mpMRI, number of cores, operation time, and biopsy time were comparable between the groups. The VAS scores during biopsy were significantly lower in the intervention group than in the control group [2 (1 to 3) vs. 2 (1 to 4), P=0.019]. Conversely, the VNS scores during biopsy were higher in the intervention group [3 (2 to 4) vs. 3 (2 to 3), P=0.015]. There were no significant differences in the pain scores or the satisfaction scores at 30 min after the procedure between the two groups. There were no significant differences between the groups for complications, such as hematuria, urinary retention, infection, hemospermia, and vasovagal reaction (P>0.05).

Conclusions

Targeted PNB significantly relieved the pain and did not increase the incidence of complications for patients when compared with traditional PNB.

Modeling the effect of immunotherapies on human castration-resistant prostate cancer

In this paper we analyze the potential effect of immunotherapies on castration-resistant form of human Prostate Cancer (PCa). In particular, we examine the potential effect of the dendritic vaccine sipuleucel-T, the only currently available immunotherapy option for advanced PCa, and of ipilimumab, a drug targeting the Cytotoxic T-Lymphocyte Antigen 4 (CTLA4), exposed on the CTLs membrane, currently under Phase II clinical trial. The model, building on the one by Rutter and Kuang, includes different types of immune cells and interactions and is parameterized on available data. Our results show that the vaccine has only a very limited effect on PCa, while repeated treatments with ipilimumab appear potentially capable of controlling and even eradicating an androgen-independent prostate cancer. From a mathematical analysis of a simplified model, it seems likely that, under continuous administration of ipilimumab, the system lies in a bistable situation where both the no-tumor equilibrium and the high-tumor equilibrium are attractive. The schedule of periodic treatments could then determine the outcome, and mathematical models could help determine an optimal schedule.

Clonal evaluation of prostate cancer molecular heterogeneity in biopsy samples by dual immunohistochemistry and dual RNA in situ hybridization

Prostate cancer is frequently multifocal. Although there may be morphological variation, the genetic underpinnings of each tumor are not clearly understood. To assess the inter and intra tumor molecular heterogeneity in prostate biopsy samples, we developed a combined immunohistochemistry and RNA in situ hybridization method for the simultaneous evaluation of ERG, SPINK1, ETV1, and ETV4. Screening of 601 biopsy cores from 120 consecutive patients revealed multiple alterations in a mutually exclusive manner in 37% of patients, suggesting multifocal tumors with considerable genetic differences. Furthermore, the incidence of molecular heterogeneity was higher in African Americans patients compared with Caucasian American patients. About 47% of the biopsy cores with discontinuous tumor foci showed clonal differences with distinct molecular aberrations. ERG positivity occurred in low-grade cancer, whereas ETV4 expression was observed mostly in high-grade cancer. Further studies revealed correlation between the incidence of molecular markers and clinical and pathologic findings, suggesting potential implications for diagnostic pathology practice, such as defining dominant tumor nodules and discriminating juxtaposed but molecularly different tumors of different grade patterns.

Pre-clinical evaluation of an image-guided in-situ Raman spectroscopy navigation system for targeted prostate cancer interventions

PURPOSE

Transrectal ultrasound (TRUS) image guidance is the standard of care for diagnostic and therapeutic interventions in prostate cancer (PCa) patients, but can lead to high false-negative rates, compromising downstream effectiveness of therapeutic choices. A promising approach to improve in-situ detection of PCa lies in using the optical properties of the tissue to discern cancer from healthy tissue. In this work, we present the first in-situ image-guided navigation system for a spatially tracked Raman spectroscopy probe integrated in a PCa workflow, capturing the optical tissue fingerprint. The probe is guided with fused TRUS/MR imaging and tested with both tissue-simulating phantoms and ex-vivo prostates. The workflow was designed to be integrated the clinical workflow for trans-perineal prostate biopsies, as well as for high-dose rate (HDR) brachytherapy.

METHODS

The proposed system developed in 3D Slicer includes an electromagnetically tracked Raman spectroscopy probe, along with tracked TRUS imaging automatically registered to diagnostic MRI. The proposed system is tested on both custom gelatin tissue-simulating optical phantoms and biological tissue phantoms. A random-forest classifier was then trained on optical spectrums from ex-vivo prostates following prostatectomy using our optical probe. Preliminary in-human results are presented with the Raman spectroscopy instrument to detect malignant tissue in-situ with histopathology confirmation.

RESULTS

In 5 synthetic gelatin and biological tissue phantoms, we demonstrate the ability of the image-guided Raman system by detecting over 95% of lesions, based on biopsy samples. The included lesion volumes ranged from 0.1 to 0.61 cc. We showed the compatibility of our workflow with the current HDR brachytherapy setup. In ex-vivo prostates of PCa patients, the system showed a 81% detection accuracy in high grade lesions.

CONCLUSION

Pre-clinical experiments demonstrated promising results for in-situ confirmation of lesion locations in prostates using Raman spectroscopy, both in phantoms and human ex-vivo prostate tissue, which is required for integration in HDR brachytherapy procedures.

Pelvic plexus block to provide better anesthesia in transperineal template-guided prostate biopsy: a randomised controlled trial

Background

To evaluate the efficacy of pelvic plexus block (PPB) in relief pain during transperineal template-guided prostate biopsy (TTPB), compared with conventional periprostatic nerve block (PNB).

Methods

From July 2016 to August 2017, 245 patients who were performed TTPB in Clinical Medical College of Yangzhou University were recruited. The patients were randomized into three groups using a random number table. Group-1 received prostate capsule local anesthesia with 22 ml of 1% lidocaine. Group-2 additionally received PNB on the basis of Group-1. To perform PNB, 5 ml 1% lidocaine was injected into the region of prostatic neurovascular bundle situated in the angle of prostate-bladder-seminal vesicle. Group-3 received prostate capsule local anesthesia plus PPB (5 ml of 1% lidocaine injection into the pelvic plexus which located on lateral to the bilateral seminal vesicle apex). The patients’ pain and satisfaction were evaluated by visual analogue scale and visual numerical scale, respectively.

Results

The age, total prostate volume, PSA and the number of cores were comparable among the three groups. The visual analog scale scores of group-3 were significantly lower than group-2 during biopsy (P = 0.003). Conversely, the visual numeric scale scores were higher in group-3 (P = 0.039). Both the group-2 and group-3 outperformed the group-1 in alleviating pain and had a higher quantification of satisfaction. There were no significant differences in the pain scores or the satisfaction scores at 30 min after the procedure among the three groups.

Conclusions

The analgesic efficacy of PPB guided by Doppler ultrasound in TTPB was better than that of PNB and both were superior to no nerve block.

Trial registration

ChiCTR-IOR-17013533, 01/06/2016.

Intratumoral Injection of Low-Energy Photon-Emitting Gold Nanoparticles: A Microdosimetric Monte Carlo-Based Model

Gold nanoparticles (Au NPs) distributed in the vicinity of low-dose rate (LDR) brachytherapy seeds could multiply their efficacy thanks to the secondary emissions induced by the photoelectric effect. Injections of radioactive LDR gold nanoparticles (LDR Au NPs), instead of conventional millimeter-size radioactive seeds surrounded by Au NPs, could further enhance the dose by distributing the radioactivity more precisely and homogeneously in tumors. However, the potential of LDR Au NPs as an emerging strategy to treat cancer is strongly dependent on the macroscopic diffusion of the NPs in tumors, as well as on their microscopic internalization within the cells. Understanding the relationship between interstitial and intracellular distribution of NPs, and the outcomes of dose deposition in the cancer tissue is essential for considering future applications of radioactive Au NPs in oncology. Here, LDR Au NPs (¹⁰³Pd:Pd@Au-PEG NPs) were injected in prostate cancer tumors. The particles were visualized at time-points by computed tomography imaging ( in vivo), transmission electron microscopy ( ex vivo), and optical microscopy ( ex vivo). These data were used in a Monte Carlo-based dosimetric model to reveal the dose deposition produced by LDR Au NPs both at tumoral and cellular scales. ¹⁰³Pd:Pd@Au-PEG NPs injected in tumors produce a strong dose enhancement at the intracellular level. However, energy deposition is mainly confined around vesicles filled with NPs, and not necessarily close to the nuclei. This suggests that indirect damage caused by the production of reactive oxygen species might be the leading therapeutic mechanism of tumor growth control, over direct damage to the DNA.

Effect of prostate volume on the peripheral nerve block anesthesia in the prostate biopsy: A strobe-compliant study

OBJECTIVE

The objective of this study was to evaluate the anesthetic efficacy of periprostatic nerve block (PNB) in transrectal ultrasound (TRUS)-guided biopsy on different prostate volume.

METHODS

A total of 568 patients received prostate biopsy in our hospital from May 2013 to September 2015 and were retrospectively studied. All patients were divided into local anesthesia group (LAG) and nerve block group (NBG). Then each group was subdivided into 4 subgroups (20-40, 40-60, 60-100, and >100 mL groups) according to different prostate volume range. Visual analogue scale (VAS) and visual numeric scale (VNS) were used to assess the patient's pain and quantify their satisfaction. The scores and complications were compared between the groups.

RESULTS

The age and serum prostate-specific antigen (PSA) level before biopsy had no significant differences at intergroup or intragroup level. The VAS scores were significantly lower in the NBG than those in the LAG in terms of prostate volume (1 (1-2) versus 2 (1-3), 2 (1-3) versus 2 (2-4), 2 (2-3) versus 3 (2-5), 4 (3-5) versus 5 (4-7), all P < 0.05). Conversely, the VNS scores were higher in the NBG (4 (3-4) versus 3.5 (3-4), 3 (3-4) versus 3 (3-3), 3 (2-4) versus 3 (2-3), 2 (2-2) versus 1 (1-2), all P < 0.05). Patients with smaller prostate volume undergoing PNB or local anesthesia experienced significantly lower pain and higher satisfaction scores than those with large prostate. Whether in PNB or local anesthesia group, patients with large prostate volume had more chance to have hematuria, hemospermia, urinary retention than smaller one except infection (P < 0.05). Those complications had no significant differences between LAG and NBG (P > 0.05).

CONCLUSION

Compared with local anesthesia, ultrasound-guided PNB has superior analgesic effect and equal safety, but for patients with a large prostate volume, the analgesic effect is inefficient.