Primary full-gland prostate cryoablation in older men (> age of 75 years): results from 860 patients tracked with the COLD Registry

Primary cryotherapy for localized prostate cancer treatment

INTRODUCTION

Prostate cryotherapy is an available treatment option for localized prostate cancer (PC) included on minimal invasive therapies but still under evaluation. We started our cryotherapy program in 2008 for selected patients with localized PC. Our objective is to evaluate the oncologic and functional outcomes of primary cryotherapy in men with clinically localized PC.

SUBJECTS AND METHODS

We retrospectively evaluated all patients who underwent primary cryotherapy for localized PC treatment at our center between January 2008 and December 2017. In order to downsize prostates between 40 and 60cc neoadjuvant 3-month hormonal therapy was administered. Primary endpoint was biochemical progression-free survival (BPFS) rate as defined by the Phoenix criteria. Secondary endpoints were cancer-specific survival (CSS), overall survival (OS), patient reported functional outcomes and complication rates. Factors influencing de BPFS were evaluated individually using Kaplan-Meyer and Cox regression models and in a multivariate model using Cox regression.

RESULTS

During the mentioned period, a total of 177 men were treated with cryotherapy. With a mean follow-up of 60 months (SD 32.9), the Kaplan-Meier analysis shows an overall BPFS rate was 67%. BPFS by risk group was 70.2%, 70.3% and 50.0% for the low, intermediate and high risk groups, respectively (p = 0.925). Overall time to BR was 93.67 months (SD 2.84, IC95%: 88.10-99.24): 95.91 (SD 3,44), 93.23 (SD 4.81) and 89.77 (SD 6.67) months for the low, intermediate and high risk groups, respectively. In both univariate and multivariate analysis, the only predictor of biochemical progression was de PSA nadir (HR 1.56 IC95%: 1.50-1.63). Continence was fully maintained in 95% of patients after the procedure. Postoperative complications included UTI (17.5%), hematuria (9.6%), perineal hematoma (11%) and postoperative pain (4.5%). No fistulas were reported. 8.5% of patients had acute urinary retention solved conservatively.

CONCLUSION

Cryotherapy is a safe option for selected patients with localized prostate cancer that provides competitive oncologic outcomes and a low morbidity profile.

Current status and future prospective of focal therapy for localized prostate cancer: development of multiparametric MRI, MRI-TRUS fusion image-guided biopsy, and treatment modalities

Multiparametric magnetic resonance imaging (mpMRI) has been increasingly used to diagnose clinically significant prostate cancer (csPC) because of its usefulness in combination with anatomic and functional data. MRI-targeted biopsy, such as MRI-transrectal ultrasound (TRUS) fusion image-guided prostate biopsy, has high accuracy in the detection and localization of csPC. This novel diagnostic technique contributes to the development of tailor-made medicine as focal therapy, which cures the csPC while preserving the anatomical structures related to urinary and sexual function. In the early days of focal therapy, TRUS-guided systematic biopsy was used for patient selection, and treatment was performed for patients with low-risk PC. With the introduction of mpMRI and mapping biopsy, the treatment range is now determined based on individualized cancer localization. In recent prospective studies, 87.4% of treated patients had intermediate- and high-risk PC. However, focal therapy has two main limitations. First, a randomized controlled trial would be difficult to design because of the differences in pathological features between patients undergoing focal therapy and radical treatment. Therefore, pair-matched studies and/or historical controlled studies have been performed to compare focal therapy and radical treatment. Second, no long-term (≥ 10-year) follow-up study has been performed. However, recent prospective studies have encouraged the use of focal therapy as a treatment strategy for localized PC because it contributes to high preservation of continence and erectile function.

Functional outcomes after prostatic cryosurgery

OBJECTIVE

To assess the functional effects of prostatic cryosurgery on micturition.

MATERIAL AND METHODS

Prospective study of men who underwent cryosurgery (CS) for prostate cancer between 2013 - 2015. Low urinary tract symptoms (LUTS) and quality of life (QoL) were assessed 1 month before surgery using IPSS questionnaire, a three-day voiding diary (3DVD) and uroflowmetry with ultrasound-measured postvoid residual volume. Need of medical treatment for LUTS was also recorded. The same assessment was performed at 3, 6 and 12 months after CS. Outcomes after surgery were compared to those prior to surgery.

RESULTS

Forty-five patients underwent a CS during the study period, of whom 25 patients could be recruited in the study. Mean age was 73.5 years (range 66-84). Nineteen CS (76%) were performed as a primary procedure, while 6 CS (24%) as a salvage procedure. No statistical differences were found comparing results of IPSS, QoL, D3vd or uroflowmetry and PVR at 3, 6 or 12 months after CS compared to before surgery. Before CS, 8 (32%) patients were on medical treatment for LUTS, while at 6 and 12 months after surgery, 3 (13.6%) and 2 (9.5%) patients required some medication, respectively.

CONCLUSION

According to the punctuation of IPSS, QoL questionnaire, and a 3-day voiding diary, LUTS does not worsen after CS. Prostatic cryosurgery does not seem to impact uroflowmetry results.

Avoidance of androgen deprivation therapy in radiorecurrent prostate cancer as a clinically meaningful endpoint for salvage cryoablation

BACKGROUND

To investigate the ability of salvage cryoablation of the prostate (SCAP) to delay the need for androgen deprivation therapy (ADT) in local recurrence after radiation therapy to the prostate using the Cryo-On-Line Database (COLD) registry.

METHODS

The COLD registry is comprised of a combination of retrospectively and prospectively collected data on patients undergoing primary and SCAP. Patients with local recurrence after radiation therapy were identified. Kaplan-Meier analysis was used to calculate ADT-free survival.

RESULTS

We identified 898 patients that have undergone SCAP in the COLD registry. Overall, the calculated 5-year ADT-free survival probability was 0.713. When stratified by D'Amico risk group, 264 high-risk patients (71.9%), 234 intermediate-risk (86.7%),and 228 low-risk (87.7%) were free of ADT post-SCAP. This correlates with a 5-year ADT-free survival of 60.7, 73.9, and 82.4%, respectively. Patients with post-SCAP PSA nadir of <0.2 ng/mL had a 5 year ADT-free survival of 87.1% compared to 48.7% with a PSA nadir ≥0.2 ng/mL. Pre-operative ADT use or full versus partial gland SCAP did not have an effect on ADT use post-operatively. In 118 (55.4%) of patients with post-operative biochemical recurrence, ADT was not used.

CONCLUSION

For patients with local recurrence after radiation, SCAP is an option that provides a high chance of avoiding or delaying ADT. The potential to delay ADT and its associated side effects should be a part of counseling sessions with the patient when discussing treatment options for locally recurrent prostate cancer after radiation. Avoidance of ADT is more clinically relevant than PSA elevation.

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.

Management of Prostate Cancer in the Elderly

The impact of localized prostate cancer in the elderly depends on disease aggressiveness and life expectancy. In men with localized prostate cancer, those with low-risk disease or a shorter life expectancy should be managed expectantly, whereas those with long life expectancy or more aggressive disease may benefit from curative treatment. Comorbidity and quality-of-life concerns are key considerations during the selection of therapeutic modalities in the elderly in localized and metastatic settings. A variety of new agents have changed the therapeutic landscape in castrate-resistant prostate cancer, but their benefits need to be considered alongside their side effects and cost.

A pretreatment nomogram for prediction of biochemical failure after primary cryoablation of the prostate

BACKGROUND

To create a predictive nomogram for biochemical failure following primary whole-gland cryoablation of the prostate for localized prostate cancer (LPCa).

METHODS

We retrospectively analyzed 2,242 patients from the Cryo On-Line Database (COLD) who were treatment naive and had undergone primary whole gland cryoablation of the prostate for biopsy-confirmed LPCa. Kaplan-Meier (KM) curves estimating 5 year biochemical progression-free survival (bPFS) were generated. Multivariable Cox proportional hazards analysis (CoxPH) was performed in order to construct the nomogram. The nomogram was internally validated using the bootstrap technique.

RESULTS

Overall, the KM estimated 5 year bPFS was 72.8%. Stratified by D'Amico risk, The KM estimated 5 year bPFS was 82.6%, 71.1%, and 57.8% for low-, intermediate-, and high-risk groups, respectively. Statistically significant predictors of biochemical outcomes from CoxPH analysis were pre-treatment prostate specific antigen (PTPSA) (P < 0.001), total prostate volume (P = 0.004), clinical stage (P = 0.034), and Gleason score (0.004). A nomogram for predicted 5 year biochemical progression free probability was constructed with a concordance index of 0.652. An online risk calculator was also generated.

CONCLUSIONS

To the best of our knowledge, this is the first predictive nomogram for biochemical outcomes after primary whole gland cryoablation of the prostate using socio-demographic, pretreatment, clinical, and prostate biopsy data. Our nomogram and online risk calculator can guide both patients and urologists for shared decision making regarding definitive treatment options.

Comparison of Outcomes Between Preoperatively Potent Men Treated with Focal Versus Whole Gland Cryotherapy in a Matched Population

BACKGROUND AND PURPOSE

The refinement in the localization of prostate cancer tumor foci through transperineal template-mapping biopsies and MRI has led to an increased interest in lesion-directed focal prostatic cryoablation. Data are lacking, however, that compare the outcomes of whole-gland (WG) to focal ablation therapy (FT). The aim of our study was to assess both oncologic and functional outcomes between WG and FT cryoablation of the prostate after having matched patients for preoperative characteristics.

PATIENTS AND METHODS

We matched with a 1:1 ratio 317 men who underwent FT with 317 who underwent WG treatment in the Cryo Online Data (COLD) registry between 2007 and 2013. All patients were low-risk according to the D'Amico risk groups and were matched according to age at surgery. We only included preoperatively potent men. Oncologic outcomes were biochemical recurrence (BCR) free-survival defined according to the American Society for Radiation Oncology (ASTRO) and Phoenix criteria and assessed by Kaplan-Meier curves. Only patients with prostate-specific antigen (PSA) nadir data were included in oncologic outcome analysis. Functional outcomes were assessed at 6, 12, and 24 months after the procedure for erectile function (defined as ability to have intercourse with or without erectile aids), urinary continence, urinary retention, and rates of fistula formation.

RESULTS

Median age at the time of the procedure was 66.5 years (standard deviation [SD] 6.6 y), and median follow-up time was 58.3 months. After surgery, 30% (n=95) and 17% (n=55) of the men who received WG and FT, respectively, underwent biopsy, with positive biopsy rates of 11.6% and 14.5%, respectively. BCR-free survival rates at 60 months according to the Phoenix definition were 80.1% and 71.3% in the WG and FT cohorts, respectively, with a hazard ratio of 0.827; according to the ASTRO definition, they were 82.1% and 73%, respectively (all P ≥ 0.1). Erectile function data at 24 months was available for 172 WG and 160 FT treated men. Recovery of erection was achieved in 46.8% and 68.8% of patients in the WG and FT cohorts, respectively (P=0.001). Urinary function data at 24 months was available for 307 WG and 313 FT patients. Continence rates were 98.7% and 100% for WG and FT groups, respectively (P=0.02). Urinary retention at 6, 12, and 24 months was reported in 7.3%, 1.9%, and 0.6%, respectively, in the WG arm, and in 5%, 1.3%, and 0.9%, respectively, in the FT arm. Finally, only one fistula was reported in each group.

CONCLUSIONS

Men with low-risk prostate cancer who underwent FT cryoablation had comparable BCR-survival rates at 60 months to patients treated with WG. However, FT patients had higher erectile function preservation rates at 24 months post-procedure. Urinary continence, retention and fistula rates were similar between the two treatment groups.

Re-purposing cryoablation: a combinatorial 'therapy' for the destruction of tissue

It is now recognized that the tumor microenvironment creates a protective neo-tissue that isolates the tumor from the various defense strategies of the body. Evidence demonstrates that, with successive therapeutic attempts, cancer cells acquire resistance to individual treatment modalities. For example, exposure to cytotoxic drugs results in the survival of approximately 20-30% of the cancer cells as only dividing cells succumb to each toxic exposure. With follow-up treatments, each additional dose results in tumor-associated fibroblasts secreting surface-protective proteins, which enhance cancer cell resistance. Similar outcomes are reported following radiotherapy. These defensive strategies are indicative of evolved capabilities of cancer to assure successful tumor growth through well-established anti-tumor-protective adaptations. As such, successful cancer management requires the activation of multiple cellular 'kill switches' to prevent initiation of diverse protective adaptations. Thermal therapies are unique treatment modalities typically applied as monotherapies (without repetition) thereby denying cancer cells the opportunity to express defensive mutations. Further, the destructive mechanisms of action involved with cryoablation (CA) include both physical and molecular insults resulting in the disruption of multiple defensive strategies that are not cell cycle dependent and adds a damaging structural (physical) element. This review discusses the application and clinical outcomes of CA with an emphasis on the mechanisms of cell death induced by structural, metabolic, vascular and immune processes. The induction of diverse cell death cascades, resulting in the activation of apoptosis and necrosis, allows CA to be characterized as a combinatorial treatment modality. Our understanding of these mechanisms now supports adjunctive therapies that can augment cell death pathways.

Cryotherapy with concurrent CpG oligonucleotide treatment controls local tumor recurrence and modulates HER2/neu immunity

Percutaneous cryoablation is a minimally invasive procedure for tumor destruction, which can potentially initiate or amplify antitumor immunity through the release of tumor-associated antigens. However, clinically efficacious immunity is lacking and regional recurrences are a limiting factor relative to surgical excision. To understand the mechanism of immune activation by cryoablation, comprehensive analyses of innate immunity and HER2/neu humoral and cellular immunity following cryoablation with or without peritumoral CpG injection were conducted using two HER2/neu(+) tumor systems in wild-type (WT), neu-tolerant, and SCID mice. Cryoablation of neu(+) TUBO tumor in BALB/c mice resulted in systemic immune priming, but not in neu-tolerant BALB NeuT mice. Cryoablation of human HER2(+) D2F2/E2 tumor enabled the functionality of tumor-induced immunity, but secondary tumors were refractory to antitumor immunity if rechallenge occurred during the resolution phase of the cryoablated tumor. A step-wise increase in local recurrence was observed in WT, neu-tolerant, and SCID mice, indicating a role of adaptive immunity in controlling residual tumor foci. Importantly, local recurrences were eliminated or greatly reduced in WT, neu tolerant, and SCID mice when CpG was incorporated in the cryoablation regimen, showing significant local control by innate immunity. For long-term protection, however, adaptive immunity was required because most SCID mice eventually succumbed to local tumor recurrence even with combined cryoablation and CpG treatment. This improved understanding of the mechanisms by which cryoablation affects innate and adaptive immunity will help guide appropriate combination of therapeutic interventions to improve treatment outcomes.

Cryotherapy for primary treatment of prostate cancer: intermediate term results of a prospective study from a single institution

Purpose. Published data about cryotherapy for prostate cancer (PC) treatment are based on case series with a lack of clinical trials and the inexistence of a validated definition of biochemical failure. A prospective study with standardized followup protocol was conducted in our institution. Material and Methods. Prospective study of a series of cases including 108 patients diagnosed with localized PC at clinical stage T1c-T2c treated by primary cryoablation and median followup of 61 months. Criteria of biochemical recurrence were unified according to the American Society for Therapeutic Radiology and Oncology (ASTRO). End points were biochemical progression-free survival (BPFS), cancer-specific survival, and overall survival. Rate of complications was reported. Results. The BPFS for low-, medium-, and high-risk patients was 96.4%, 91.2%, and 62.2%, respectively. Cancer-specific survival was 98.1%. Overall survival reached 94.4%. Complications included incontinence in 5.6%, urinary tract obstruction in 1.9%, urethral sloughing in 5.6%, haematuria in 1.9%, perineal pain in 11.1%, and prostatorectal fistula in 0.9%. Erectile disfunction was found in 98.1%. Conclusions. Cryotherapy is an effective and minimally invasive treatment for primary PC in well-selected cases, with low surgical risk and good results in terms of BPFS, cancer-specific survival, and overall survival.

Oncological outcome after primary prostate cryoablation compared with radical prostatectomy: a single-centre experience

OBJECTIVE

The aim of this study was to evaluate the oncological outcome after cryoablation of the prostate (CAP) in localized prostate cancer and to compare the results with those of the established treatment of radical prostatectomy (RP) after 7 years of parallel use.

MATERIAL AND METHODS

Forty primary, whole-gland CAP procedures performed on 39 patients from 2006 until 2012 at the Department of Urology, Aarhus University Hospital, were prospectively registered. Patients had a minimum of 12 months' follow-up if they had no recurrent disease. Recurrence was defined by the Phoenix criterion (nadir PSA + 2 ng/ml). Results were compared with oncological outcome in 350 patients who underwent RP over the same period.

RESULTS

Median follow-up after CAP was 29.5 (range 4-75) months. Median age at the time of treatment was 65 (47-78) years. A total of 13 (33%) patients developed recurrent disease after CAP, and in D'Amico low-, intermediate- and high-risk subgroups, recurrence was found in two (33%), five (24%) and six (46%), respectively. Median follow-up after RP was 37 (16-54) months. No cases were excluded. Median age was 64 (34-76) years. Compared with the RP results, where recurrence was found in 62 cases in total (18%), and in three (3%), 30 (21%) and 29(28%) subdivided into risk groups, the risk of recurrent disease was significantly higher after the CAP procedures (p < 0.001).

CONCLUSIONS

Recurrence after CAP was high regardless of risk group, indicating a risk of treating and leaving the tumour in situ. Even small low-risk tumours have the potential for recurrence. At this institution, the oncological outcome after CAP was inferior to that after RP.

Comparison of biochemical failure definitions for predicting local cancer recurrence following cryoablation of the prostate

BACKGROUND

Various definitions of biochemical failure (BF) have been used to predict cancer recurrence following prostate cryoablation. However to date, none of these definitions have been validated for this use. We have reviewed several definitions of BF to determine their accuracy in predicting biopsy-proven local recurrence following prostate cryoablation.

METHODS

The Columbia University Urologic Oncology Database was queried for patients who underwent prostate cryoablation between 1994 and 2010, and who subsequently underwent surveillance biopsy due to clinical suspicion of prostate cancer recurrence. Serial postoperative prostate-specific antigen (PSA) results were used to determine BF according to various definitions of BF. Biopsy results were used to determine local recurrence. Sensitivity, specificity, positive and negative predictive value, and receiver operating characteristic (ROC) curve area were calculated for each of the BF definitions.

RESULTS

A total of 110 patients met inclusion criteria for the study. These patients were treated with primary full-gland (n = 38), primary focal (n = 24), or salvage cryoablation (n = 48). On surveillance biopsy, 66 patients (60%) were found to have locally recurrent prostate cancer. The most accurate BF definition overall was PSA nadir plus 2 ng/ml (Phoenix definition), with sensitivity, specificity, and ROC curve area of 68%, 59%, and 0.64, respectively.

CONCLUSIONS

Overall, the Phoenix definition best predicted local cancer recurrence following prostate cryoablation. These preliminary data may be useful for researchers evaluating the short-term efficacy of cryoablation, and for urologists assessing their patients for potential cancer recurrence.

Focal therapy in the management of prostate cancer: an emerging approach for localized prostate cancer

A widespread screening with prostate-specific antigen (PSA) has led increased diagnosis of localized prostate cancer along with a reduction in the proportion of advanced-stage disease at diagnosis. Over the past decade, interest in focal therapy as a less morbid option for the treatment of localized low-risk prostate cancer has recently been renewed due to downward stage migration. Focal therapy stands midway between active surveillance and radical treatments, combining minimal morbidity with cancer control. Several techniques of focal therapy have potential for isolated ablation of a tumor focus with sparing of uninvolved surround tissue demonstrating excellent short-term cancer control and a favorable patient's quality of life. However, to date, tissue ablation has mostly used for near-whole prostate gland ablation without taking advantage of accompanying the technological capabilities. The available ablative technologies include cryotherapy, high-intensity focused ultrasound (HIFU), and vascular-targeted photodynamic therapy (VTP). Despite the interest in focal therapy, this technology has not yet been a well-established procedure nor provided sufficient data, because of the lack of randomized trial comparing the efficacy and morbidity of the standard treatment options. In this paper we briefly summarize the recent data regarding focal therapy for prostate cancer and these new therapeutic modalities.