Ten-year biochemical disease control for patients with prostate cancer treated with cryosurgery as primary therapy

Optical Sensing of Tissue Freezing Depth by Sapphire Cryo-Applicator and Steady-State Diffuse Reflectance Analysis

This work describes a sapphire cryo-applicator with the ability to sense tissue freezing depth during cryosurgery by illumination of tissue and analyzing diffuse optical signals in a steady-state regime. The applicator was manufactured by the crystal growth technique and has several spatially resolved internal channels for accommodating optical fibers. The method of reconstructing freezing depth proposed in this work requires one illumination and two detection channels. The analysis of the detected intensities yields the estimation of the time evolution of the effective attenuation coefficient, which is compared with the theoretically calculated values obtained for a number of combinations of tissue parameters. The experimental test of the proposed applicator and approach for freezing depth reconstruction was performed using gelatin-based tissue phantom and rat liver tissue in vivo. It revealed the ability to estimate depth up to 8 mm. The in vivo study confirmed the feasibility of the applicator to sense the freezing depth of living tissues despite the possible diversity of their optical parameters. The results justify the potential of the described design of a sapphire instrument for cryosurgery.

Survival After Cryotherapy Versus Radiotherapy in Low and Intermediate Risk Localized Prostate Cancer

BACKGROUND

Focal therapy, including cryotherapy, reduces overtreatment in low- and intermediate-risk prostate cancer (PCa) patients with multiple comorbidities, which seems to increase in popularity compared with whole gland treatment. However, there is currently no consensus regarding the medium-term outcomes of cryosurgery as a prospective alternative to radiotherapy (RT) for such patients. Our study aims to find the available evidence that directly compares the medium-term overall survival (OS) and cancer-specific mortality (CSM) outcomes between cryotherapy and RT in patients with low- and intermediated-risk PCa.

MATERIALS AND METHOD

Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 47,787 patients with low- and intermediate-risk PCa diagnosed between 2004 and 2015, of which 46,853 (98%) received treatment with RT, while only 934 (2.0%) received treatment with cryotherapy. Kaplan-Meier methods were used to estimateOS and cancer-specific survival (CSS) between the 2 groups. We performed multivariable Cox regression analysis to assess overall mortality (OM), while the cumulative incidence function (CIF) was used to illustrate cancer-specific mortality (CSM) and noncancer-specific mortality (non-CSM) for all patients. Additionally, competing risks regression (Fine-Gray) was implemented to evaluate any differences. After propensity score matching (PSM), all the aforementioned analyses were repeated. After the inverse probability of treatment weighting (IPTW), we repeated Kaplan-Meier methods on OS and CSS, and performed multivariable Cox regression analysis to assess OM in cryotherapy versus RT. Sensitivity analyses were conducted by excluding patients who died of cardiovascular disease.

RESULTS

After applying 1:4 PSM to the cryotherapy group with the RT group, the resulting RT cohort consisted of 3,736 patients who were matched with 934 patients in the cryotherapy cohort. The 5-year OS and cumulative CSM rates for PS-matched groups (N = 4670) receiving cryotherapy (N = 934) or RT (N = 3736) were 89% versus 91.8%, 0.65% versus 0.57, respectively. Multivariable Cox regression analysis demonstrated that cryotherapy was associated with a poorer OS outcome compared to RT (hazard ratio [HR] 1.29, 95% confidence interval [CI]: 1.07-1.55, p < .01). Multivariate competing risk regression analysis revealed that both treatments were not associated with CSS, with HR = 1.07 (95% CI: 0.55-2.08, p = .85). IPTW-adjusted analyses showed that the 5-years OS rates were 89.6% versus 91.8% for cryotherapy versus RT, respectively. Multivariate regression analysis for OS demonstrated that cryotherapy was more likely to have inferior OS in comparison to RT (HR = 1.30; 95%CI: 1.09-1.54; p < .01). The outcome of sensitivity analyses indicates that there was no significant difference in OS and CSS between the 2 groups.

CONCLUSION

For low- and intermediate-risk PCa patients treated by cryotherapy or RT, we could not demonstrate a survival difference. Cryotherapy may be a feasible option as a viable alternative to traditional radiation therapy.

Primary Whole-gland Ablation for the Treatment of Clinically Localized Prostate Cancer: A Focal Therapy Society Best Practice Statement

CONTEXT

Whole-gland ablation is a feasible and effective minimally invasive treatment for localized prostate cancer (PCa). Previous systematic reviews supported evidence for favorable functional outcomes, but oncological outcomes were inconclusive owing to limited follow-up.

OBJECTIVE

To evaluate the real-world data on the mid- to long-term oncological and functional outcomes of whole-gland cryoablation and high-intensity focused ultrasound (HIFU) in patients with clinically localized PCa, and to provide expert recommendations and commentary on these findings.

EVIDENCE ACQUISITION

We performed a systematic review of PubMed, Embase, and Cochrane Library publications through February 2022 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. As endpoints, baseline clinical characteristics, and oncological and functional outcomes were assessed. To estimate the pooled prevalence of oncological, functional, and toxicity outcomes, and to quantify and explain the heterogeneity, random-effect meta-analyses and meta-regression analyses were performed.

EVIDENCE SYNTHESIS

Twenty-nine studies were identified, including 14 on cryoablation and 15 on HIFU with a median follow-up of 72 mo. Most of the studies were retrospective (n = 23), with IDEAL (idea, development, exploration, assessment, and long-term study) stage 2b (n = 20) being most common. Biochemical recurrence-free survival, cancer-specific survival, overall survival, recurrence-free survival, and metastasis-free survival rates at 10 yr were 58%, 96%, 63%, 71-79%, and 84%, respectively. Erectile function was preserved in 37% of cases, and overall pad-free continence was achieved in 96% of cases, with a 1-yr rate of 97.4-98.8%. The rates of stricture, urinary retention, urinary tract infection, rectourethral fistula, and sepsis were observed to be 11%, 9.5%, 8%, 0.7%, and 0.8%, respectively.

CONCLUSIONS

The mid- to long-term real-world data, and the safety profiles of cryoablation and HIFU are sound to support and be offered as primary treatment for appropriate patients with localized PCa. When compared with other existing treatment modalities for PCa, these ablative therapies provide nearly equivalent intermediate- to long-term oncological and toxicity outcomes, as well as excellent pad-free continence rates in the primary setting. This real-world clinical evidence provides long-term oncological and functional outcomes that enhance shared decision-making when balancing risks and expected outcomes that reflect patient preferences and values.

PATIENT SUMMARY

Cryoablation and high-intensity focused ultrasound are minimally invasive treatments available to selectively treat localized prostate cancer, considering their nearly comparable intermediate- to long term cancer control and preservation of urinary continence to other radical treatments in the primary setting. However, a well-informed decision should be made based on one's values and preferences.

Intermediate-term oncological and functional outcomes of salvage cryotherapy for the management of prostate cancer recurrence after primary brachytherapy versus primary cryotherapy: A propensity score-matched analysis

BACKGROUND

Salvage cryotherapy (SCT) is widely used to treat prostate cancer (PCa) recurrence after radiotherapy (RT). We studied the intermediate oncological and functional outcomes of patients who underwent SCT following cryotherapy (CRYO-SCT) recurrence and compare it to recurrence after brachytherapy (BT-SCT).

METHODS

An IRB-approved retrospective cohort study utilizing patient data from the Cryo On-Line Data Registry and the Duke PCa database between 1992 and 2016. Biochemical recurrence (BCR) using Phoenix criteria was the primary endpoint assessed at 2- and 5-years post-SCT. Secondary endpoints assessed functional outcomes including urinary continence, erectile function, and recto-urethral fistula. Association between treatment and biochemical progression-free survival was assessed using inverse probability weighted (IPTW) Cox proportional hazards regression. The differences in the secondary functional outcomes were assessed by Pearson's χ2 test or Fisher's exact test, corrected for IPTW.

RESULTS

A total of 194 patients met inclusion criteria. The BCR rate for BT-SCT and CRYO-SCT was 23 (20.4%) and 17 (21%) at 2 years and 30 (26.5%) and 22 (27.2%) at 5 years according to Phoenix criteria. There was no statistical difference in 2 years (hazard ratio [HR] 0.9; 95% confidence interval [CI], 0.5-1.7, p = 0.7) or 5-year BCR (HR: 0.86; 95% CI, 0.5-1.5, p = 0.6) between the groups. The functional outcomes like urinary continence (p = 0.4), erectile function (p = 0.1), and recto-urethral fistula (p = 0.3) were not statistically different.

CONCLUSION

CRYO-SCT appears to be well tolerated, with comparable oncological and functional outcomes to patients failing primary BT. The findings also demonstrated that SCT can render a significant number of patients biochemically free of disease after initial CRYO with minimal morbidity. SCT is a viable treatment option to salvage local PCa recurrence following either BT or cryoablation failure.

Prostate cryoablation combined with androgen deprivation therapy for newly diagnosed metastatic prostate cancer: a propensity score-based study

BACKGROUND

Several studies showed that androgen deprivation therapy (ADT) plus local treatment of prostate could improve metastatic prostate cancer (mPCa) patients' survival. To date there are few studies analyzed the value of prostate cryoablation in mPCa. The objective of our analysis is to evaluate the oncological results and clinical value of prostate cryoablation combined with ADT compared with ADT alone in newly diagnosed mPCa patients.

METHODS

Newly diagnosed mPCa patients undergoing cryoablation plus ADT (group A) between January 2011 and November 2018 were identified. Patients receiving ADT alone (group B) were selected from the same institutional prostate cancer database by propensity score matching based on clinical characteristics. Oncological results and clinical value in symptom control and primary lesion treatment were compared.

RESULTS

Fifty-four patients were included in each group. Prostate cryoablation was well tolerated. The median follow-up time was 40 (27-53) and 39 (31-54) months in group A and group B, respectively. Patients in group A had a lower median prostate-specific antigen (PSA) nadir (0.025 ng/mL vs. 0.230 ng/mL, p = 0.001), longer median failure-free survival (FFS) (39 months vs. 21 months, p = 0.005), and median metastatic castration-resistant prostate cancer (mCRPC)-free survival (39 months vs. 21 months, p = 0.007). No difference in cancer-specific survival and overall survival was found between the two groups. Multivariate Cox analysis showed combination therapy reduced the risk of FFS by 45.8% (HR = 0.542 [95% CI 0.329-0.893]; p = 0.016). Patients in group A had better clinical relief of urinary symptoms (79.1 vs. 59.1%, p = 0.044) and required less treatment of primary lesions for symptomatic relief (13.0 vs. 31.5%, p = 0.021).

CONCLUSIONS

Prostate cryoablation plus ADT decreases PSA nadir, prolongs FFS and mCRPC-free survival, relieves urinary symptoms and reduces the need for treating primary lesions in newly diagnosed mPCa patients compared to ADT alone.

Evaluation of a Novel Cystoscopic Compatible Cryocatheter for the Treatment of Bladder Cancer

BACKGROUND: As the acceptance of cryoablative therapies for the treatment of non-metastatic cancers continues to grow, avenues for novel cryosurgical technologies and approaches have opened. Within the field of genitourinary tumors, cryosurgical treatments of bladder cancers remain largely investigational. Current modalities employ percutaneous needles or transurethral cryoballoons or sprays, and while results have been promising, each technology is limited to specific types and stages of cancers. OBJECTIVE: This study evaluated a new, self-contained transurethral cryocatheter, FrostBite-BC, for its potential to treat bladder cancer. METHODS: Thermal characteristics and ablative capacity were assessed using calorimetry, isothermal analyses, in vitro 3-dimensional tissue engineered models (TEMs), and a pilot in vivo porcine study. RESULTS: Isotherm assessment revealed surface temperatures below – 20°C within 9 sec. In vitro TEMs studies demonstrated attainment of ≤– 20°C at 6.1 mm and 8.2 mm in diameter following single and double 2 min freezes, respectively. Fluorescent imaging 24 hr post-thaw revealed uniform, ablative volumes of 326.2 mm3 and 397.9 mm3 following a single or double 2 min freeze. In vivo results demonstrated the consistent generation of ablative areas. Lesion depth was found to correlate with freeze time wherein 15 sec freezes resulted in ablation confined to the sub-mucosa and ≥30 sec full thickness ablation of the bladder wall. CONCLUSIONS: These studies demonstrate the potential of the FrostBite-BC cryocatheter as a treatment option for bladder cancer. Although preliminary, the outcomes of these studies were encouraging, and support the continued investigation into the potential of the FrostBite-BC cryocatheter as a next generation, minimally invasive cryoablative technology.

Cryotherapy shows no inferiority compared with radical Prostatectomy for low-risk and intermediate-risk localized Prostate Cancer: a real-world study from the SEER database

Background: For localized prostate cancer (PCa) with a low disease burden, whole-gland resection seems like overtreatment, while focal therapy, including cryosurgery, can achieve similar outcomes. We aimed at comparing the long-term survival outcomes of cryotherapy and radical prostatectomy (RP) and further exploring whether RP can be replaced by cryosurgery for those with low-risk PCa.

Methods: We conducted analyses from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2015) and performed propensity score matching and used an instrumental variate to reduce the influence of bias and unmeasured confounders to the greatest extent.

Results: In the multivariate regression, patients who received cryotherapy had higher risk of overall mortality (OM) (hazard ratio [HR] = 2.52, 95% confidence interval [CI] 1.99-3.20, p < 0.001), but no significant difference was observed in decreasing cancer-specific mortality (CSM) (HR = 1.38, 95% CI 0.63-3.03, p = 0.41) after adjusting the confounders. After propensity score matching, patients who underwent cryotherapy had higher OM and CSM rates (HR = 2.70 [95% CI 1.99-3.66, p < 0.001] and HR = 2.99 [95% CI 1.19-7.48, p = 0.02], respectively). In the IV-adjusted analyses, RP was superior to cryotherapy in decreasing OM (HR = 2.52, 95% CI 1.99-3.20), while no obvious decrease of CSM was observed in the comparison of RP and cryotherapy (HR = 1.38, 95% CI 0.63-3.03). The subgroup analyses showed that RP displayed an obvious benefit in decreasing CSM (HR = 5.02, 95% CI 1.30-19.39, p = 0.02) for those with a prostate-specific antigen (PSA) level higher than 10 ng/ml.

Conclusion: RP ranked as the best treatment in regard to tumor control, but the advantages of cryotherapy became evident when taking functional and oncological outcomes into account, especially for low- and intermediate-risk PCa with low PSA levels.

Cryoablation: physical and molecular basis with putative immunological consequences

Cryoablation (CA) is unique as the singular energy deprivation therapy that impacts all cellular processes. CA is independent of cell cycle stage and degree of cellular stemness. Importantly, CA is typically applied as a non-repetitive (single session) treatment that does not support adaptative mutagenesis as do many repetitive therapies. CA is characterized by the launch of multiple forms of cell death including (a) ice-related physical damage, (b) initiation of cellular stress responses (kill switch activation) and launch of necrosis and apoptosis, (c) vascular stasis, and (d) likely activation of ablative immune responses. CA is not without limitation related to the thermal gradient formed between cryoprobe surface (∼-185°C) and the distal surface of the freeze zone (∼0°C) requiring freeze margin extension beyond the tumor boundary (up to ∼1 cm). This limitation is mitigated in part by commonly applied dual freeze thaw cycles and the use of freeze sensitizing adjuvants. This review will (1) identify the cascade of damaging effects of the freeze-thaw process, its physical and molecular-based relationships, (2) a likely immunological involvement (abscopic effect), and (3) explore the use of freeze-sensitizing adjuvants necessary to limit freezing beyond the tumor margin.

[Percutaneous MR-guided prostate cancer cryoablation: Predictive factors and oncologic outcomes]

OBJECTIVE

To determine the pejorative predictive factors on oncologic outcomes of percutaneous MR-guided whole gland prostate cancer cryoablation (CA).

METHODS

Medical records of patients treated from 2009 to 2012, to assess medium-term oncologic outcomes, were reviewed. Prostate biopsies were performed in local recurrence suspicion (biochemical failure, MR follow-up failure).

RESULTS

Among 18 patients, mean age of 72.6 (61-78), 2 (11 %) and 7 (38.9 %) biological and reported biopsy-proven local recurrence respectively with our initial technic of CA. Mean follow-up and recurrence were 56.3 (±21.7) and 20.7 (±13.9) months respectively. A previous treatment of prostate cancer (P=0.5), pre-treatment PSA (P=0.2), pre-treatment Gleason/ISUP score (P=0.4), nadir PSA post-CA (P=0.22) were not associated with recurrence. Bilateral positive cores appears as a pejorative predictive factor (P=0.04). However mean pre-treatment positive cores percentage, 25 (±16.5) in responding patients versus 40.7 (±25.2) in case of recurrence, and maximum percentage of cancer extent in each positive core, 10.6 (±9.3) in responding patients versus 18.7 (±16.5) in case of recurrence, seemed associated with local recurrence after prostate CA but our analysis wasn't able to find a difference (P=0.09 and P=0.3 respectively) due to a lack of power.

CONCLUSION

Bilateral positive cores appears as a pejorative predictive factor. In our experience, important tumor volume seem to be a pejorative predictive factor for oncologic outcomes after PCA whereas treatment, PSA, Gleason/ISUP score, nadir PSA are not.

LEVEL OF EVIDENCE

4.

Percutaneous MR-guided prostate cancer cryoablation technical updates and literature review

Prostate cancer (PCa) is the most common malignant tumor in males. The benefits in terms of overall reduction in specific mortality due to the widespread use of Prostate Specific Antigen (PSA) screening and the advancements in the curative treatments (radical prostatectomy or radiotherapy) appear to have reached a plateau. There remains, however, the questions of overdiagnosis and overtreatment of such patients. Currently, the main challenge in the treatment of patients with clinically organ-confined PCa is to offer an oncologically efficient treatment with as little morbidity as possible. Amongst the arising novel curative techniques for PCa, cryoablation (CA) is the most established one, which is also included in the NICE and AUA guidelines. CA is commonly performed under ultrasound guidance with the inherent limitations associated with this technique. The recent advancements in MRI have significantly improved the accuracy of detecting and characterizing a clinically significant PCa. This, alongside the development of wide bore interventional MR scanners, has opened the pathway for in bore PCa treatment. Under MRI guidance, PCa CA can be used either as a standard whole gland treatment or as a tumor targeted one. With MR-fluoroscopy, needle guidance capability, multiplanar and real-time visualization of the iceball, MRI eliminates the inherent limitations of ultrasound guidance and can potentially lead to a lower rate of local complications. The aim of this review article is to provide an overview about PCa CA with a more specific insight on MR guided PCa CA; the limitations, challenges and applications of this novel technique will be discussed.

Defeating Cancers' Adaptive Defensive Strategies Using Thermal Therapies: Examining Cancer's Therapeutic Resistance, Ablative, and Computational Modeling Strategies as a means for Improving Therapeutic Outcome

BACKGROUND

Diverse thermal ablative therapies are currently in use for the treatment of cancer. Commonly applied with the intent to cure, these ablative therapies are providing promising success rates similar to and often exceeding "gold standard" approaches. Cancer-curing prospects may be enhanced by deeper understanding of thermal effects on cancer cells and the hosting tissue, including the molecular mechanisms of cancer cell mutations, which enable resistance to therapy. Furthermore, thermal ablative therapies may benefit from recent developments in computer hardware and computation tools for planning, monitoring, visualization, and education.

METHODS

Recent discoveries in cancer cell resistance to destruction by apoptosis, autophagy, and necrosis are now providing an understanding of the strategies used by cancer cells to avoid destruction by immunologic surveillance. Further, these discoveries are now providing insight into the success of the diverse types of ablative therapies utilized in the clinical arena today and into how they directly and indirectly overcome many of the cancers' defensive strategies. Additionally, the manner in which minimally invasive thermal therapy is enabled by imaging, which facilitates anatomical features reconstruction, insertion guidance of thermal probes, and strategic placement of thermal sensors, plays a critical role in the delivery of effective ablative treatment.

RESULTS

The thermal techniques discussed include radiofrequency, microwave, high-intensity focused ultrasound, laser, and cryosurgery. Also discussed is the development of thermal adjunctive therapies-the combination of drug and thermal treatments-which provide new and more effective combinatorial physical and molecular-based approaches for treating various cancers. Finally, advanced computational and planning tools are also discussed.

CONCLUSION

This review lays out the various molecular adaptive mechanisms-the hallmarks of cancer-responsible for therapeutic resistance, on one hand, and how various ablative therapies, including both heating- and freezing-based strategies, overcome many of cancer's defenses, on the other hand, thereby enhancing the potential for curative approaches for various cancers.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU – Actualisation 2018–2020 : cancer de la prostate French ccAFU guidelines – Update 2018–2020: Prostate cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: DOI:10.1016/j.purol.2019.01.007. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the DOI:10.1016/j.purol.2019.01.007. That newer version of the text should be used when citing the article.

Assessment of a novel cryoablation device for the endovascular treatment of cardiac tachyarrhythmias

Objectives

Cryoablation is an effective alternative treatment for cardiac arrhythmias offering shortened recovery and reduced side effects. As the use of cryoablation increases, the need for new devices and procedures has emerged. This has been driven by technological limitations including lengthy periods to generate a single lesion (3-5 min), uncertain transmurality, and differential efficacy. Furthermore, due to limited ablation capacity under high heat loads, cryo has had limited success in the treatment of ventricular arrhythmias. To this end, in this study we evaluated a new cryoablation catheter, ICEolate, for the targeted ablation of cardiac tissue.

Methods

Performance assessment included calorimetry, freeze zone isothermal distribution characterization and catheter ablation capacity in a submerged, circulating, heat-loaded ex vivo tissue model. A pilot in vivo study was also conducted to assess ablative capacity of the cryocatheter in a fully beating heart.

Results

Ex vivo studies demonstrated ice formation at the tip of a cryocatheter within 5 s and a tip temperature of ~-150°C within 10 s. The device repeatedly generated freeze zones of 2 cm × 3 cm in less than 2 min. Tissue model studies revealed the generation of a full thickness (5-10 mm) cryogenic lesion within 1 min with an opposite (transmural) surface temperature of <-60°C under a circulating 37°C heat load. Pilot in vivo studies demonstrated the delivery of an ablative "dose," producing a continuous full thickness transmural linear lesion in <60 s at both atrial and ventricular sites.

Conclusion

These studies suggest that the supercritical nitrogen cryodevice and ICEolate cryocatheter may provide for rapid, effective, controllable freezing of targeted tissue. The ablative power, speed, and directional freeze characteristics also offer the potential of improved safety via a reduction in procedural time compared to current cryoablation devices. These technological developments may open new avenues for the application of cryo to treat other cardiac arrhythmogenic disorders.

Adjuvant androgen-deprivation therapy following prostate total cryoablation in high-risk localized prostate cancer patients - Open-labeled randomized clinical trial

PURPOSE

To investigate the efficacy and safety profile of 12-month adjuvant androgen-deprivation therapy (ADT) following total-gland cryoablation (TGC) in patients with high-risk localized prostate cancer (HRLPC).

MATERIALS AND METHODS

This open-label randomized trial included 38 HRLPC patients who received TGC between July 2011 and March 2013. Within 4 weeks after TGC, subjects were randomly assigned (1:1) to either the 12-month adjuvant ADT or non-adjuvant ADT group. The primary outcome was biochemical failure measured by the Phoenix definition. Adverse events were measured at month 1, 2, 3, 6, 9 and 12. In addition, a cohort of 145 HRLPC patients was selected retrospectively for outcome validation.

RESULTS

The adjuvant ADT and non-adjuvant ADT groups did't differ in peri-operative characters, such as age, preoperative PSA, tumor stages, Gleason score, prostate size and cryoprobe number. Four patients with adjuvant ADT withdrew from this trial for personal reasons (N = 2), elevated liver function (N = 1) and poorly controlled hyperglycemia (N = 1). In contrast, none in non-adjuvant ADT group experienced adverse events. Biochemical failures were identified in 5 (26%) patients in each group during a median follow-up duration of 45 months. The median times to biochemical failure were 25 and 5.5 months for adjuvant ADT and non-adjuvant ADT groups, respectively. Biochemical-failure survival curves converged 24 months after TGC. Univariable and multivariable analyses revealed adjuvant ADT was not associated with biochemical recurrences in the validation cohort.

CONCLUSIONS

Adjuvant ADT does not reduce biochemical failure for HRPLC patients undergoing TGC. It should be further confirmed by a larger cohort.

Clinically Localized Prostate Cancer: AUA/ASTRO/SUO Guideline. Part I: Risk Stratification, Shared Decision Making, and Care Options

PURPOSE

This guideline is structured to provide a clinical framework stratified by cancer severity to facilitate care decisions and guide the specifics of implementing the selected management options. The summary presented represents Part I of the two-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO/SUO Guideline discussing risk stratification and care options by cancer severity.

MATERIALS AND METHODS

The systematic review utilized in the creation of this guideline was completed by the Agency for Healthcare Research and Quality and through additional supplementation by ECRI Institute. This review included articles published between January 2007 and March 2014 with an update search conducted through August 2016. When sufficient evidence existed, the body of evidence for a particular treatment was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. Additional information is provided as Clinical Principles and Expert Opinions (table 2 in supplementary unabridged guideline, http://jurology.com/).

RESULTS

The AUA (American Urological Association), ASTRO, and SUO (Society of Urologic Oncology) formulated an evidence-based guideline based on a risk stratified clinical framework for the management of localized prostate cancer.

CONCLUSIONS

This guideline attempts to improve a clinician's ability to treat patients diagnosed with localized prostate cancer, but higher quality evidence in future trials will be essential to improve the level of care for these patients. In all cases, patient preferences should be considered when choosing a management strategy.

Effects of Focal vs Total Cryotherapy and Minimum Tumor Temperature on Patient-reported Quality of Life Compared With Active Surveillance in Patients With Prostate Cancer

OBJECTIVE

To investigate the effects of focal (hemiablation) or total cryotherapy and minimum tumor temperature on patient-reported quality of life (QoL) in patients with prostate cancer.

METHODS

An Institutional Review Board-approved database was reviewed for patients who underwent cryotherapy or active surveillance (AS). QoL questionnaire responses were collected and scores were analyzed for differences between focal and total cryotherapy and between very cold (<-76°C) and moderate-cold (≥-76°C) minimum tumor temperatures.

RESULTS

A total of 197 patients responded to a total of 547 questionnaires. Focal and total cryotherapy patients had initially lower sexual function scores relative to AS (year 1 mean difference focal: -31.7, P <.001; total: -48.1, P <.001). Focal cryotherapy was associated with a more rapid improvement in sexual function. Both focal and total cryotherapy sexual function scores were not statistically significantly different from the AS cohort by postprocedural year 4. Very cold and moderate-cold temperatures led to initially lower sexual function scores relative to AS (year 1 very cold: -38.1, P <.001; moderate-cold: -30.7, P <.001). Moderate-cold temperature scores improved more rapidly than those of very cold temperature. Neither very cold nor moderate-cold temperatures had a statistically significant difference in sexual function scores relative to AS by postprocedural year 4. Urinary function and bowel habits were not significantly different between focal and total cryotherapy and between very cold and moderate-cold temperature groups.

CONCLUSION

Focal cryotherapy and moderate-cold (≥-76°C) temperature were associated with favorable sexual function relative to total cryotherapy and very cold temperature, respectively. No significant differences in urinary function or bowel habits were observed between groups.

[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.

[CCAFU french national guidelines 2016-2018 on prostate cancer]

OBJECTIVES

The purpose of the guidelines national committee CCAFU was to propose updated french guidelines for localized and metastatic prostate cancer (PCa).

METHODS

A Medline search was achieved between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of PCa, to evaluate different references with levels of evidence.

RESULTS

Epidemiology, classification, staging systems, diagnostic evaluation are reported. Disease management options are detailed. Recommandations are reported according to the different clinical situations. Active surveillance is a major option in low risk PCa. Radical prostatectomy remains a standard of care of localized PCa. The three-dimensional conformal radiotherapy is the technical standard. A dose of > 74Gy is recommended. Moderate hypofractionation provides short-term biochemical control comparable to conventional fractionation. In case of intermediate risk PCa, radiotherapy can be combined with short-term androgen deprivation therapy (ADT). In case of high risk disease, long-term ADT remains the standard of care. ADT is the backbone therapy of metastatic disease. In men with metastases at first presentation, upfront chemotherapy combined with ADT should be considered as a new standard. In case of metastatic castration-resistant PCa (mCRPC), new hormonal treatments and chemotherapy provide a better control of tumor progression and increase survival.

CONCLUSIONS

These updated french guidelines will contribute to increase the level of urological care for the diagnosis and treatment for prostate cancer. © 2016 Elsevier Masson SAS. All rights reserved.

Assessment of Cryosurgical Device Performance Using a 3D Tissue-Engineered Cancer Model

As the clinical use of cryoablation for the treatment of cancer has increased, so too has the need for knowledge on the dynamic environment within the frozen mass created by a cryoprobe. While a number of factors exist, an understanding of the iceball size, critical isotherm distribution/penetration, and the resultant lethal zone created by a cryoprobe are critical for clinical application. To this end, cryoprobe performance is typically characterized based on the iceball size and temperature penetration in phantom gel models. Although informative, these models do not provide information as to the impact of heat input from surrounding tissue nor give any information on the ablative zone created. As such, we evaluated the use of a tissue-engineered tumor model (TEM) to assess cryoprobe performance including iceball size, real-time thermal profile distribution, and resultant ablative zone. Studies were conducted using an Endocare V-probe cryoprobe, with a 10/5/10 double freeze–thaw protocol using prostate and renal cancer TEMs. The data demonstrate the generation of a 33- to 38-cm3 frozen mass with the V-Probe cryoprobe following the double freeze of which ∼12.7 and 6.5 cm3 was at or below −20°C and −40°C, respectively. Analysis of ablation zone using fluorescence microscopy 24 hours postthaw demonstrated that the internal ∼40% of the frozen mass was completely ablated, whereas in the periphery of the iceball (outer 1 cm region), a gradient of partial to minimal destruction was observed. These findings correlated well with clinical reports on renal and prostate cancer cryoablation. Overall, this study demonstrates that TEMs provide an effective model for a more complete characterization of cryoablation device performance. The data demonstrate that while the overall iceball size generated in the TEM was consistent with published reports from phantom models, the integration of an external heat load, circulation, and cellular components more closely reflect an in vivo setting and the impact of penetration of the critical (−20°C and −40°C) isotherms into the tissue. This is important as it is well appreciated in clinical practice that the heat load of a tissue, cryoprobe proximity to vasculature, and so on, can impact outcome. The TEM model provides a means of characterizing the impact on ablative dose delivery allowing for a better understanding of probe performance and potential impact on ablative outcome.

Safety and efficacy of a China-made cryoablation device in treatment of hepatocellular carcinoma smaller than 5 cm

AIM

To assess the safety and efficacy of a China-made cryoablation device in the treatment of hepatocellular carcinoma (HCC) smaller than 5 cm.

METHODS

A total of 33 patients with HCC smaller than 5 cm were treated by cryoablation using a China-made cryoablation device under the guidance of computed tomography. Operation-associated complications within and after procedures were evaluated. The efficacy of target lesions within procedures and local recurrence rate after procedures were evaluated with imaging modalities.

RESULTS

All 37 lesions of the 33 patients were successfully treated with a China-made cryablation device. Upon the finish of procedures, complete ablation was achieved in 83.78% (31/37) of lesions, and partial ablation was achieved in 16.22% (6/37). In a median follow-up period of 10.8 mo, 32 patients remained alive and 1 was lost to follow-up. The rate of local recurrence for target lesions was 30.3% (10/33), which is equal to that achieved with imported devices.

CONCLUSION

Our findings suggest that the China-made cryoablation device is safe and effective for HCC smaller than 5 cm with the capability of destroying the whole tumor lesion.

Salvage robotic prostatectomy following whole gland high-intensity focused ultrasound with a Sonablate 500 device: technical feasibility and safety

High-intensity focused ultrasound (HIFU) has been used to treat localized prostate cancers. Similar to all forms of ablation, including radiation and cryoablation, there is a local persistence rate. Salvage robotic prostatectomy has been utilized but published series are multi-institutional, multi-surgeon, and do not segregate the different HIFU devices. The results are also grouped with other forms of ablation. This series describes the technical results of a single surgeon performing salvage robotic prostatectomy on only HIFU patients, and only after whole gland ablation on a Sonablate 500 device. A retrospective hospital and office chart review was performed of nine consecutive patients. Results of the surgical cases reveal an acceptable mean OR time of 130 min, mean estimated blood loss of 125 cc with no intraoperative or post-operative transfusions, and mean length of hospital stay of 2.4 days. Urinary catheters were removed after 7-10 days. All patients were pad free no longer than 35 days later. There was no surgical field or systemic complications in any patient. Intraoperative findings include diffuse fibrosis of the periprostatic tissues including the endopelvic and lateral pelvic fascia. The thermal changes make the surgery more tedious, particularly for nerve sparing. These cases support the stance that robotic salvage prostatectomy can be safely performed in this patient cohort with immediate surgical results similar to non-salvage cases.

Salvage local therapy for radiation-recurrent prostate cancer - where are we?

INTRODUCTION

Prostate cancer is the most frequent cancer among males in Europe and a leading cause of cancer deaths, with similar proportion in other developed countries. For more than twenty years, external-beam radiation therapy, alongside with radical prostatectomy, has been used as a primary radical therapeutic approach for localized prostate cancer. Yet, EBRT failures relate to 22-69% following curative radiotherapy (± androgen deprivation therapy). Additionally, a proportion of these men will have a biopsy-proven local recurrence.

MATERIAL AND METHODS

The Medline and Web of Science databases were searched without a time limit during March 2016 using the terms 'prostate cancer' in conjunction with 'radiotherapy', 'recurrence', 'biochemical', 'salvage', 'brachytherapy', 'prostatectomy', 'HIFU', 'cryotherapy' and 'focal'. The search was limited to the English, Polish, German and Spanish literature.

RESULTS

Currently, salvage treatment after failed radiotherapy includes radical prostatectomy, brachytherapy and ablative whole-gland therapies, such as cryotherapy and high intensity focused ultrasound. New approaches, so called focal salvage therapy, involve ablation of only the zone of recurrence in order to decrease tissue injury and therefore to diminish morbidity.

CONCLUSIONS

At present no authoritative recommendations can be concluded because of the absence of randomized data with standardized definitions and protocols. Nevertheless, we believe that local salvage treatment should be at least considered in patients after biochemical relapse following radiotherapy.

Investigation of the Impact of Cell Cycle Stage on Freeze Response Sensitivity of Androgen-Insensitive Prostate Cancer

BACKGROUND

Cryoablation, an effective means of ablating cancer, is often used in conjunction with adjuvants that target cancer cells in a specific cell cycle stage to increase treatment efficacy. The objective of this study was to investigate the impact of cell cycle stage on cancer freeze response as well as investigate the potential cellular kinetic effect of calcitriol, the active metabolic of vitamin D3, when used as a cryosensitizing adjuvant in order to maximize prostate cancer cell death.

METHODS

Cell cycle distribution of PC-3 cells was analyzed via flow cytometry to compare gap 1, synthesis, and gap 2/mitosis phase subpopulations pre- and postfreeze as well as changes elicited by calcitriol pretreatment. Distinct gap 1, synthesis, and gap 2/mitosis phase populations were obtained through fluorescence-activated cell sorting and synthesis phase thymidine synchronization. Posttreatment viability was assessed using alamarBlue and fluorescence microscopy to assess live, apoptotic, and necrotic subpopulations.

RESULTS

A small but statistically significant increase in synthesis phase and decrease in gap 2/mitosis phase populations was noted at 6 hours postfreeze in asynchronous samples. Synchronization in synthesis phase yielded an increase in cell death when combined with freezing to both -15°C and -20°C. Calcitriol pretreatment increased the gap 1 phase population by 20% and a synergistic decrease in viability following freezing. However, gap 1-sorted populations combined with calcitriol treatment did not exhibit this synergistic effect. Fluorescence microscopy of fluorescence-activated cell sorting-sorted cells revealed necrosis as the predominant form of cell death in all phases, though apoptosis did play a role.

CONCLUSION

Although initial results suggested a potential sensitivity, PC-3 cells exposed to freezing as sorted populations did not reveal significant differences in cell death. As such, the data from this study suggest that there is no difference in cell cycle stage sensitivity to freezing injury.

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.

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.

Oncological outcomes of cryosurgery as primary treatment in T3 prostate cancer: experience of a single centre

OBJECTIVE

To assess the oncological outcomes and determine prognostic factors for overall survival (OS), cancer-specific survival (CSS), and biochemical progression-free survival (BPFS) after cryosurgery for clinical stage T3 prostate cancer.

PATIENTS AND METHODS

Between 2002 and 2007, 75 patients with clinical stage T3 prostate cancer received cryosurgery as primary treatment in our institution. No adjuvant treatment was provided until biochemical failure. After biochemical failure, hormone therapy was administered. Kaplan-Meier analysis was used to calculate the OS, CSS, and BPFS. Cox regression was used to identify factors predictive of survival.

RESULTS

Clinical stage T3a (cT3a) was detected in 60% (45/75) of patients and cT3b detected in 40% (30/75). The 5-year OS, CSS, and BPFS rates were 85.3%, 92.0%, and 48%, respectively. There was a significant difference when comparing the pT3a with the pT3b group for 5-year OS (88.9% vs 80%, P = 0.02) and BPFS (55.6% vs 36.7%, P = 0.01), but there was no difference in CSS (93.3% vs 90%, P = 0.63). Stage, Gleason score, and nadir prostate-specific antigen (PSA) were associated with BPFS, while Gleason score and nadir PSA were the most significant predictors for CSS.

CONCLUSIONS

Cryosurgery can offer good 5-year OS, CSS, and BPFS rates for cT3 prostate cancer, and there was no difference between T3a and T3b for CSS. Gleason score and nadir PSA were the most significant predictors of survival. Further clinical trials are warranted for evaluating the role of cryosurgery for cT3 prostate cancer.

Current status of cryotherapy for prostate and kidney cancer

In terms of treating diseases, minimally invasive treatment has become a key element in reducing perioperative complications. Among the various minimally invasive treatments, cryotherapy is often used in urology to treat various types of cancers, especially prostate cancer and renal cancer. In prostate cancer, the increased incidence of low-risk, localized prostate cancer has made minimally invasive treatment modalities an attractive option. Focal cryotherapy for localized unilateral disease offers the added benefit of minimal morbidities. In renal cancer, owing to the increasing utilization of cross-sectional imaging, nearly 70% of newly detected renal masses are stage T1a, making them more susceptible to minimally invasive nephron-sparing therapies including laparoscopic and robotic partial nephrectomy and ablative therapies. This article reviews the various outcomes of cryotherapy compared with other treatments and the possible uses of cryotherapy in surgery.

Predictors of prostate-specific antigen biochemical recurrence in patients undergoing primary whole-gland prostate cryoablation

PURPOSE

Cryoablation has been proven as a less invasive, safe, and effective treatment for localized prostate cancer. We attempted to identify the predictors of biochemical recurrence after prostate cryoablation for localized prostate cancer in this study.

METHODS

We reviewed 114 patients who underwent primary whole-gland prostate cryoablation for localized prostate cancer from October 2008 to March 2013. The perioperative parameters included age >70 years, initial prostate-specific antigen (PSA), preoperative prostate volume, Gleason score, T stage, D'Amico risk group, postoperative PSA nadir, time to PSA nadir, and PSA biochemical recurrence, defined by Phoenix definition (nadir plus 2 ng/mL). Receiver operating characteristic (ROC) analysis was used for the best cutoff value of PSA nadir for PSA biochemical recurrence. The parameters were analyzed in binary logistic regression and Kaplan-Meier analysis for PSA biochemical recurrence.

RESULTS

A total of 31.6 % (N = 36) patients had PSA biochemical recurrence during the median follow-up of 34.87 ± 16.49 months. ROC analysis revealed that the best cutoff value for biochemical recurrence prediction was when the PSA nadir = 0.3 ng/mL. On multivariate analysis and Kaplan-Meier analysis, the D'Amico high-risk group [hazard ratio (HR) 6.552; p = 0.014], PSA nadir >0.3 ng/mL (HR 34.062; p < 0.001), and time to PSA nadir <3 months (HR 4.144; p = 0.021) were statistically significant for PSA biochemical recurrence.

CONCLUSIONS

The D'Amico high-risk group, postoperative PSA nadir >0.3 ng/mL, and time to PSA nadir <3 months predict biochemical recurrence in primary whole-gland prostate cryoablation.

Cryotherapy in prostate cancer

Review objectives:

Cryotherapy use has increased due to technological advances. A review of the literature was performed to evaluate the efficacy and outcomes of whole gland, salvage and targeted focal cryotherapy in the management of prostate cancer.

Review findings:

Cryotherapy use has increased significantly over the last 10 years with a trend towards focal ablation. Whole gland cryotherapy, salvage cryotherapy and focal cryotherapy biochemical recurrence rates appear to be comparable to other treatment modalities for low risk disease, however biochemical failure remains difficult to compare across studies due to a lack of consensus regarding appropriate end points for evaluation of cryotherapy. Short-term focal cryotherapy outcomes are encouraging. Side effect profiles for cryotherapy have significantly improved with fourth generation systems while salvage cryotherapy continues to carry a slightly higher risk of incontinence than primary whole gland cryotherapy. The incidence of erectile dysfunction after focal cryotherapy is dramatically lower than that for whole gland ablation.

Conclusions:

Cryotherapy continues to have an active role in the primary and salvage treatment of prostate cancer. Targeted focal cryotherapy is a promising treatment with minimal morbidity. Further long-term data is needed to support targeted therapy in addition to direct comparison with other treatment modalities.

Surgical management of prostate cancer

Surgery remains a mainstay in the management of localized prostate cancer. This article addresses surgical aspects germane to the management of men with prostate cancer, including patient selection for surgery, nerve-sparing approaches, minimization of positive surgical margins, and indications for pelvic lymph node dissection. Outcomes for men with high-risk prostate cancer following surgery are reviewed, and the present role of neoadjuvant therapy before radical prostatectomy is discussed. In addition, there is a review of the published literature on surgical ablative therapies for prostate cancer.

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.

Primary cryosurgery for clinically localized prostate cancer--do perioperative tumor characteristics correlate with post-treatment biopsy results?

OBJECTIVE

To investigate the rate and predictive factors of positive post-treatment biopsy in men treated with primary cryosurgery for localized prostate cancer.

METHODS

A retrospective review was performed of all patients treated with primary cryosurgery at a single institution between 1999 and 2012. Perioperative prostate-specific antigen (PSA) levels, Gleason score, and number of positive preoperative biopsy cores were obtained and correlated with postoperative biopsy results. Patients were stratified according to the risk classification system of D'Amico to low-, intermediate-, or high-risk groups.

RESULTS

Sixty-five men were treated with primary cryosurgery, and 57 of 65 (88%) of them underwent postoperative biopsy on average 9 months after the treatment. Eleven of 57 patients (19%) were found to have persistent tumor on post-treatment biopsy. Men who had positive biopsy had significantly higher perioperative PSA levels than men who had negative biopsy (preoperative PSA 12.5 vs 6.2, P = .002; post-operative PSA nadir 4.3 vs 0.71, P = .005); however, no independent predictor was found on a multivariate analysis. Gleason score and number of positive preoperative biopsy cores did not predict tumor persistence. Positive biopsy results were found more often in the intermediate- and high-risk patients, although this was not statistically significant (low risk 9%, intermediate risk 20%, and high risk 27%).

CONCLUSION

Perioperative PSA levels, Gleason score, or number of positive pretreatment biopsy cores do not predict failure after primary cryosurgery for clinically localized prostate cancer. Our findings suggest that physicians, who offer primary cryosurgery to patients with localized prostate cancer, should consider offering post-treatment biopsy to patients to assure adequate cancer control.

Mechanisms of cryoablation: clinical consequences on malignant tumors

While the destructive actions of a cryoablative freeze cycle are long recognized, more recent evidence has revealed a complex set of molecular responses that provides a path for optimization. The importance of optimization relates to the observation that the cryosurgical treatment of tumors yields success only equivalent to alternative therapies. This is also true of all existing therapies of cancer, which while applied with curative intent; provide only disease suppression for periods ranging from months to years. Recent research has led to an important new understanding of the nature of cancer, which has implications for primary therapies, including cryosurgical treatment. We now recognize that a cancer is a highly organized tissue dependent on other supporting cells for its establishment, growth and invasion. Further, cancer stem cells are now recognized as an origin of disease and prove resistant to many treatment modalities. Growth is dependent on endothelial cells essential to blood vessel formation, fibroblasts production of growth factors, and protective functions of cells of the immune system. This review discusses the biology of cancer, which has profound implications for the diverse therapies of the disease, including cryosurgery. We also describe the cryosurgical treatment of diverse cancers, citing results, types of adjunctive therapy intended to improve clinical outcomes, and comment briefly on other energy-based ablative therapies. With an expanded view of tumor complexity we identify those elements key to effective cryoablation and strategies designed to optimize cancer cell mortality with a consideration of the now recognized hallmarks of cancer.