Primary Cryotherapy for High-Grade Clinically Localized Prostate Cancer: Oncologic and Functional Outcomes from the COLD Registry

Urinary outcomes of new ultra-minimally invasive treatments for prostate cancers

PURPOSE OF REVIEW

The aim of this narrative review is to evaluate the current available literature on urinary outcomes following cryotherapy and high-intensity focused ultrasound (HIFU) for localized prostate cancer (PCa).

RECENT FINDINGS

The available literature is heterogeneous in terms of intervention modalities and assessment of urinary outcome measures. Nevertheless, ultra-minimally invasive treatments seem to provide good urinary outcomes. Technological advancement and the adoption of more conservative ablation templates allow for a further reduction of toxicity and better preservation of urinary function. Urinary incontinence occurs in 0-10% of the patients and, is mostly transient. Voiding and storage lower urinary tract symptoms (LUTS) mostly occur in the early postoperative period and rarely require surgical treatment. Focal therapies performed with a salvage intent after external beam radiotherapy have a significantly higher impact on patient's urinary function.

SUMMARY

Ultra-minimally invasive treatment for PCa show a good safety profile concerning urinary function, but consensus on when and how best to assess this is still lacking. Efforts should be made to standardize the report of preoperative and postoperative urinary function to provide higher level of evidence.

Primary Total Prostate Cryoablation for Localized High-Risk Prostate Cancer: 10-Year Outcomes and Nomograms

The role of prostate cryoablation was still uncertain for patients with high-risk prostate cancer (PC). This study was designed to investigate 10-year disease-free survival and establish a nomogram in localized high-risk PC patients. Between October 2008 and December 2020, 191 patients with high-risk PC who received primary total prostate cryoablation (PTPC) were enrolled. The primary endpoint was biochemical recurrence (BCR), defined using Phoenix criteria. The performance of pre-operative and peri-operative nomograms was determined using the Harrell concordance index (C-index). Among the cohort, the median age and PSA levels at diagnosis were 71 years and 12.3 ng/mL, respectively. Gleason sum 8-10, stage ≥ T3a, and PSA > 20 ng/mL were noted in 27.2%, 74.4%, and 26.2% of patients, respectively. During the median follow-up duration of 120.4 months, BCR-free rates at 1, 3, 5, and 10 years were 92.6%, 76.6%, 66.7%, and 50.8%, respectively. The metastasis-free, cancer-specific, and overall survival rates were 89.5%, 97.4%, and 90.5% at 10 years, respectively. The variables in the pre-operative nomogram for BCR contained PSA at diagnosis, clinical stage, and Gleason score (C-index: 0.73, 95% CI, 0.67-0.79). The variables in the peri-operative nomogram for BCR included PSA at diagnosis, Gleason score, number of cryoprobes used, and PSA nadir (C-index: 0.83, 95% CI, 0.78-0.88). In conclusion, total prostate cryoablation appears to be an effective treatment option for selected men with high-risk PC. A pre-operative nomogram can help select patients suitable for cryoablation. A peri-operative nomogram signifies the importance of the ample use of cryoprobes and helps identify patients who may need early salvage treatment.

Focal Cryo-Immunotherapy with Intratumoral IL-12 Prevents Recurrence of Large Murine Tumors

Focal ablation technologies are routinely used in the clinical management of inoperable solid tumors but they often result in incomplete ablations leading to high recurrence rates. Adjuvant therapies, capable of safely eliminating residual tumor cells, are therefore of great clinical interest. Interleukin-12 (IL-12) is a potent antitumor cytokine that can be localized intratumorally through coformulation with viscous biopolymers, including chitosan (CS) solutions. The objective of this research was to determine if localized immunotherapy with a CS/IL-12 formulation could prevent tumor recurrence after cryoablation (CA). Tumor recurrence and overall survival rates were assessed. Systemic immunity was evaluated in spontaneously metastatic and bilateral tumor models. Temporal bulk RNA sequencing was performed on tumor and draining lymph node (dLN) samples. In multiple murine tumor models, the addition of CS/IL-12 to CA reduced recurrence rates by 30-55%. Altogether, this cryo-immunotherapy induced complete durable regression of large tumors in 80-100% of treated animals. Additionally, CS/IL-12 prevented lung metastases when delivered as a neoadjuvant to CA. However, CA plus CS/IL-12 had minimal antitumor activity against established, untreated abscopal tumors. Adjuvant anti-PD-1 therapy delayed the growth of abscopal tumors. Transcriptome analyses revealed early immunological changes in the dLN, followed by a significant increase in gene expression associated with immune suppression and regulation. Cryo-immunotherapy with localized CS/IL-12 reduces recurrences and enhances the elimination of large primary tumors. This focal combination therapy also induces significant but limited systemic antitumor immunity.

Does the type of cryoprobe affect oncological and functional outcomes in men with clinically localized prostate cancer treated with primary whole gland prostate cryoablation?

Background

This study aimed to compare the oncological and functional outcomes of primary whole gland cryoablation of the prostate using the variable ice cryoprobe (V-Probe^®) and the conventional fixed-size ice probe.

Materials and methods

We reviewed the Cryo On-Line Data Registry for men who were treated with primary whole gland prostate cryoablation from 2000 through 2017. A multivariate Cox proportional hazards model was used to compare timing to biochemical recurrence between the V-Probe^® and fixed-size ice probe after adjusting for preoperative prostate-specific antigen (PSA), neoadjuvant androgen deprivation therapy, preoperative Gleason score, and preoperative T stage.

Results

A total of 1124 men were included. Median age, Gleason score, and pretreatment PSA were 70 years (interquartile range [IQR]: 65-74 years), 7 (IQR: 6-7) and 5.9 ng/mL (IQR: 4.6-8.1 ng/mL), respectively. The median follow-up time was 25.0 months (IQR: 11.2-48.6 months). V-Probes^® were used in 269 (23.9%) cases and fixed-size ice probes in 858 (76.1%) cases. After adjusting for clinical T stage, PSA, neoadjuvant androgen deprivation therapy and preoperative Gleason score, on the multivariate Cox regression model, we found that there was no significant difference between the type of probe and timing to biochemical recurrence (p = 0.35). On multivariate logistic regression, using the V-Probe^® was associated with a 91% increase in postoperative urinary retention compared to the fixed-size ice probe (p = 0.003).

Conclusions

The use of the V-Probe^® versus conventional fixed-size ice probe was not associated with a difference in biochemical recurrence in patients undergoing primary cryoablation of the prostate.

Targeting the cancer lesion, not the whole prostate

Modern cancer treatment aims to conserve as much healthy tissue as possible. This has been challenging in the treatment of prostate cancer due to the difficulty in imaging the gland and concerns over leaving multifocal cancer untreated. With improvements in imaging and understanding of multifocal prostate cancer evidence now shows accurate treatment of just the primary focus of cancer or the index lesion can control progression or recurrence of the disease. Many different energy sources are now available to target the cancer lesion within the prostate with less significant side-effects on urinary and sexual function compared to radical treatment. Evidence shows that men value these functions highly and would even trade years of life in exchange for preserved retention of continence or erectile function. Focal treatment of prostate cancer aims to provide both cancer control and preservation of sexual and urinary functions so that men do not have to make a choice between the two. This is a treatment option that men clearly want and deserve.

Is cryosurgery a feasible local therapy for bone metastatic prostate cancer?

INTRODUCTION

This study aims to assess whether cryosurgery is a feasible local therapy for bone metastatic prostate cancer (bmPCa).

METHODS

A total of 23 patients with bmPCa who received cryosurgery and adjuvant androgen deprivation therapy (ADT) were included in the cryosurgery group (Group 1). Another 23 matched patients who received only ADT served as the control (Group 2). Prostate-specific antigen (PSA) nadir level, time to PSA nadir, time to castration-resistant prostate cancer (CRPC), progression-free survival and therapy response of bone metastases were compared between the groups.

RESULTS

The median follow-up time in Group 1 and Group 2 patients was 37 (range 19-53) months and 42 (range 24-56) months, respectively. Patients in Group 1 had fewer local complications, lower PSA nadir level (0.23 ng/mL vs. 4.01 ng/mL; p = 0.024), shorter median time to PSA nadir (3 months vs. 7 months; p < 0.001), longer median time to CRPC (36 months vs. 27 months; p = 0.002) and longer progression-free survival (35 months vs. 26 months; p = 0.003) compared to those in Group 2. Therapy responses of bone metastases were similar in the two treatment groups (p = 0.689).

CONCLUSION

Cryosurgery is a feasible local therapy for bmPCa patients with prostate volume less than 50 mL and without bulk tumours outside the prostate capsula. Cryosurgery may decrease PSA nadir level, local complications and time to PSA nadir, delay time to CRPC and improve progression-free survival.

Predictors of Rectourethral Fistula Formation After Primary Whole-Gland Cryoablation for Prostate Cancer: Results from the Cryo On-Line Database Registry

PURPOSE

To define the incidence and risk factors associated with rectourethral fistula (RUF) formation following primary whole-gland cryosurgery using a multicenter centralized registry.

PATIENTS AND METHODS

The Cryo On-Line Data (COLD) registry was queried for men undergoing primary whole-gland cryotherapy between 1990 and 2014 who developed a RUF. Patient factors and disease parameters were correlated with RUF using chi-square and the t-test. Variables with p < 0.25 were entered into a binary logistic regression with stepwise backward elimination to determine the factors associated with RUF formation.

RESULTS

A total of 4102 men underwent primary whole-gland cryotherapy in the COLD registry at the time of analysis. Postoperative RUF was documented in 50 out of 4102 cases (1.2%). Patients with RUF had similar demographic data, prostate volume, preoperative prostate-specific antigen level, and clinical stage in comparison to those without fistula. On both univariate and multivariate analyses, postoperative urinary retention (odds ratio [OR]: 6.30; confidence interval [95% CI] 3.43-11.58, p < 0.001), preoperative Gleason score of ≥7 (OR: 1.92; 95% CI 1.08-3.43, p = 0.027), and preoperative incontinence (OR: 2.95; 95% CI 1.12-7.76, p = 0.028) were the most significant risk factors associated with RUF formation.

CONCLUSION

Primary whole-gland cryotherapy for prostate cancer is associated with a historically low rate (1.2%) of postoperative RUF formation. The rate decreased further to 0.55% over the last several years, suggesting better patient selection and technical improvement. Postoperative urinary retention, Gleason score ≥7, and preoperative urinary incontinence were the key demographic, clinical, and pathologic features associated with RUF formation in this study.

Validation of the current eligibility criteria for focal therapy in men with localized prostate cancer and the role of MRI

PURPOSE

To validate current eligibility criteria for focal therapy (FT) in prostate cancer men undergoing radical prostatectomy (RP) and to assess the role of magnetic resonance imaging (MRI).

METHODS

Retrospective analysis of 217 RP patients (2009-2016) with preoperative MRI (almost all in external institutions) and fulfillment of different FT eligibility criteria: unilateral tumor, clinical tumor stage ≤ cT2a, prostate volume ≤ 60 mL and either biopsy Gleason 3 + 3 or ≤ 3 + 4 and PSA ≤ 10 or ≤ 15 ng/mL. Multivariable logistic regression analyses (MVA) assessed the role of MRI to predict the presence of significant contralateral tumor or extracapsular extension (ECE), including seminal vesicle invasion. To quantify model accuracy, Receiver Operating Characteristics-derived area under the curve (AUC) was used.

RESULTS

Of 217 patients fulfilling widest biopsy criteria and 113 fulfilling additional MRI criteria, 64 (29.7%) and 37 (32.7%) remained eligible for FT according to histopathological results. In MVA, fulfillment of MRI criteria reached independent predictor status for prediction of contralateral tumor but not for ECE. Addition of MRI resulted in AUC gain (57.5-64.6%). Sensitivity, specificity, PPV and NPV for MRI to predict contralateral tumor were: 41.8, 71.6, 70.9 and 42.6%, respectively. Virtually the same results were recorded for Gleason 3 + 3 and/or PSA ≤ 10 ng/mL.

CONCLUSIONS

Patient eligibility criteria for FT using biopsy criteria remained insufficient with respect to contralateral tumor disease. Although, MRI improves accuracy, it cannot safely exclude or minimize chance of significant cancer on contralateral prostate side. To date, stricter eligibility criteria are needed to provide more diagnostic reliability.

Focal Therapy Eligibility Determined by Magnetic Resonance Imaging/Ultrasound Fusion Biopsy

PURPOSE

We assessed focal therapy eligibility in men who underwent multiparametric magnetic resonance imaging and targeted biopsy with correlation to whole mount histology after radical prostatectomy.

MATERIALS AND METHODS

Subjects were selected from among the 454 men in whom targeted biopsy proven prostate cancer was derived from regions of interest on multiparametric magnetic resonance imaging from 2010 to 2016. Focal therapy eligibility was limited to a maximum Gleason score of 4 + 3 in regions of interest with or without other foci of low risk prostate cancer (Gleason score 3 + 3 and less than 4 mm). Men who did not meet NCCN® intermediate risk criteria were classified as ineligible for focal therapy. Of the 454 men 64 underwent radical prostatectomy and biopsy findings were compared to final pathology findings.

RESULTS

Of the 454 men with a biopsy proven region of interest 175 (38.5%) were eligible for focal therapy. Fusion biopsy, which combined targeted and template biopsy, had 80.0% sensitivity (12 of 15 cases), 73.5% specificity (36 of 49) and 75.0% accuracy (48 of 64) for focal therapy eligibility. Targeted cores alone yielded 73.3% sensitivity (11 of 15 cases), 47.9% specificity (23 of 48) and 54.7% accuracy (35 of 64). Gleason score and extension across the midline differed in 4 and 9, respectively, of the 13 cases that showed discordant biopsy and whole mount histology.

CONCLUSIONS

Using intermediate risk eligibility criteria more than a third of men with a targeted biopsy proven lesion identified on multiparametric magnetic resonance imaging would have been eligible for focal therapy. Eligibility determined by fusion biopsy was concordant with whole mount histology in 75% of cases. Improved selection criteria are needed to reliably determine focal therapy eligibility.

Neoadjuvant hormonal therapy for low-risk prostate cancer induces biochemical recurrence after radical prostatectomy via increased lymphangiogenesis-related parameters

BACKGROUND

The effects of neoadjuvant hormonal therapy (NHT) on pathological features and lymphangiogenesis in patients with prostate cancer (PCa) for each pre-operative risk classification are unclear.

METHODS

To clarify the anti-cancer effects of NHT, we investigated 153 patients (non-NHT group = 80 and NHT group = 73) who underwent radical prostatectomy (RP) in Nagasaki University Hospital. Lymph vessel density and area (evaluated by D2-40-positive vessels), vascular endothelial growth factor (VEGF)-C and VEGF-D expressions, and biochemical recurrence (BCR)-free survival were compared between these two groups for each D'Amico risk classification (low = 33, intermediate = 58, high = 62 patients).

RESULTS

In low-risk PCa patients, the risks of lymph vessel invasion and BCR were significantly higher in the NHT group than in the non-NHT group (P = 0.040 and 0.022, respectively). Such significant difference was not seen in the intermediate- or high-risk PCa groups. Lymph vessel density of the peri-tumoral and intra-tumoral areas and the lymph vessel area were significantly higher (P < 0.001) in the NHT group than in the non-NHT group in low-risk PCa. In regard to the expression of VEGF-C or VEGF-D, significant difference was not detected in low-risk PCa.

CONCLUSIONS

NHT stimulated cancer cell progression and BCR via up-regulation of lymphangiogenesis-related parameters in patients with low-risk PCa. Although VEGF-C and VEGF-D expressions were not changed by NHT, lymph vessel density and area were increased in low-risk PCa patients. We suggest that NHT for patients with low-risk PCa may have a high risk for BCR after RP.

[Evaluation and results of ablative therapies in prostate cancer]

OBJECTIVE

To perform a state of the art about methods of evaluation and present results in ablative therapies for localized prostate cancer.

METHODS

A review of the scientific literature was performed in Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of keywords. Publications obtained were selected based on methodology, language and relevance. After selection, 102 articles were analysed.

RESULTS

Analyse the results of ablative therapies is presently difficult considering the heterogeneity of indications, techniques and follow-up. However, results from the most recent and homogeneous studies are encouraging. Oncologically, postoperative biopsies (the most important criteria) are negative (without any tumor cells in the treated area) in 75 to 95%. Functionally, urinary and sexual pre-operative status is spared (or recovered early) in more than 90% of the patients treated. More and more studies underline also the correlation between the results and the technique used considering the volume of the gland and, moreover, the "index lesion" localization.

CONCLUSION

The post-treatment pathological evaluation by biopsies (targeted with MRI or, perhaps in a near future, with innovative ultrasonography) is the corner stone of oncological evaluation of ablative therapies. Ongoing trials will allow to standardize the follow-up and determine the best indication and the best techniques in order to optimize oncological and functional results for each patient treated.

Cryotherapy for Barrett's Esophagus

Cryotherapy or cryoablation involves the freezing of tissues to destroy unwanted tissue or to control bleeding. Endoscopic cryotherapy has been developed for gastrointestinal application by through-the-scope noncontact delivery of compressed carbon dioxide gas or liquid nitrogen (cryospray) or contact balloon cryoablation. The mechanism of cryotherapy ablative effects includes immediate injury as well as coagulation necrosis occurring over several hours and days, unlike heat-based thermal ablation. This article reviews the basis, technique, safety, efficacy, and durability for the use of endoscopic cryotherapy in Barrett's esophagus and esophageal adenocarcinoma.

Clinical Applications of Molecular Imaging in the Management of Prostate Cancer

At the heart of selecting an optimal management strategy for men with prostate cancer is accurately determining a given patient's clinical stage and extent of disease. Molecular imaging with PET using properly selected radiotracers offers the opportunity for improved contrast resolution over conventional imaging and thus increased sensativity for detecting sites of disease. In addition, molecular imaging provides the prospect of obtaining functional or biological information regarding a patient's cancer. To date, several PET radiotracers have been developed for prostate cancer imaging. This review summarizes the potential clinical applications of molecular imaging in the management of men with prostate cancer.

Cryosurgery would be An Effective Option for Clinically Localized Prostate Cancer: A Meta-analysis and Systematic Review

Cryosurgery (CS) has been used on patients with clinically localized PCa for more than 10 years. However, clinical studies evaluating its effectiveness and safety have reported conflicting results. This systematic assessment was performed to obtain comprehensive evidence regarding the potential benefits and safety of CS compared with those of radiotherapy (RT) and radical prostatectomy (RP), respectively. All controlled trials comparing CS with RT or RP and single-arm studies reporting results of CS therapy were identified through comprehensive searches of PubMed, the Cochrane Library and Embase. Ten publications from seven trials, with totally 1252 patients, were included in the meta-analysis, which revealed no significant differences in comparisons of CS vs RT and CS vs RP for overall survival and disease specific survival. However, a significantly lower disease-free survival could be observed for CS than RP. Moreover, a systematic review of literature focusing on comparative data of databases and materials of single-arm trials revealed satisfactory survival results in both primary and salvage CS. Our results showed that cryosurgery would be a relatively effective method for clinically localized prostate cancer with survival results comparable to radiotherapy and radical prostatectomy. However, the large percentage of complications caused by cryosurgery should be carefully monitored.