AGA Clinical Practice Guideline on Endoscopic Eradication Therapy of Barrett's Esophagus and Related Neoplasia.

BACKGROUND & AIMS: Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Endoscopic eradication therapy (EET) can be effective in eradicating BE and related neoplasia and has greater risk of harms and resource use than surveillance endoscopy. This clinical practice guideline aims to inform clinicians and patients by providing evidence-based practice recommendations for the use of EET in BE and related neoplasia. METHODS: The Grading of Recommendations Assessment, Development and Evaluation framework was used to assess evidence and make recommendations. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients, conducted an evidence review, and used the Evidence-to-Decision Framework to develop recommendations regarding the use of EET in patients with BE under the following scenarios: presence of (1) high-grade dysplasia, (2) low-grade dysplasia, (3) no dysplasia, and (4) choice of stepwise endoscopic mucosal resection (EMR) or focal EMR plus ablation, and (5) endoscopic submucosal dissection vs EMR. Clinical recommendations were based on the balance between desirable and undesirable effects, patient values, costs, and health equity considerations. RESULTS: The panel agreed on 5 recommendations for the use of EET in BE and related neoplasia. Based on the available evidence, the panel made a strong recommendation in favor of EET in patients with BE high-grade dysplasia and conditional recommendation against EET in BE without dysplasia. The panel made a conditional recommendation in favor of EET in BE low-grade dysplasia; patients with BE low-grade dysplasia who place a higher value on the potential harms and lower value on the benefits (which are uncertain) regarding reduction of esophageal cancer mortality could reasonably select surveillance endoscopy. In patients with visible lesions, a conditional recommendation was made in favor of focal EMR plus ablation over stepwise EMR. In patients with visible neoplastic lesions undergoing resection, the use of either endoscopic mucosal resection or endoscopic submucosal dissection was suggested based on lesion characteristics. CONCLUSIONS: This document provides a comprehensive outline of the indications for EET in the management of BE and related neoplasia. Guidance is also provided regarding the considerations surrounding implementation of EET. Providers should engage in shared decision making based on patient preferences. Limitations and gaps in the evidence are highlighted to guide future research opportunities.

Feasibility and safety of percutaneous intramyocardial septal cryoablation: A canine model with 6-month follow-up.

Echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation (PIMSRA, Liwen procedure) is a novel treatment option for hypertrophic obstructive cardiomyopathy (HOCM). The safety and feasibility of using this procedure for cryoablation are unknown. We aimed to investigate the feasibility and safety of echocardiography-guided percutaneous intramyocardial septal cryoablation (PIMSCA) for septal thickness reduction in a canine model. Eight canines underwent PIMSCA, and had electrocardiography, echocardiography(ECG), myocardial contrast echocardiography (MCE), serological and pathological examinations during the preoperative, immediate postoperative, and 6-month follow-up. All eight canines underwent successful cryoablation and continued to be in sinus rhythm during ablation and without malignant arrhythmias. MCE showed that the ablation area had decreased myocardial perfusion after the procedure. Troponin I levels were significantly elevated [0.010 (0.005, 0.297) ng/mL vs. 3.122 (1.152, 7.990) ng/mL, p < 0.05)]. At 6-month follow-up after the procedure, all animals were alive, with thinning of the interventricular septum (7.26 ± 0.52 mm vs. 3.86 ± 0.29 mm, p < 0.05). Echocardiography showed no significant decrease in the left ventricular ejection fractions (LVEF) (54.32 ± 2.93 % vs. 54.70 ± 2.47 %, p > 0.05) or changes by pulse-wave Doppler E/A (1.17 ± 0.43 vs. 1.07 ± 0.43, p > 0.05), E/e' (8.09 ± 1.49 vs. 10.05 ± 2.68, p > 0.05). Pathological findings proved the effectiveness of cryoablation in myocardial tissues. We observed pericardial effusions and premature ventricular complexes (PVCs) associated with the procedure. Our findings provided preliminary evidence of the safety and feasibility of PIMSCA in reducing interventricular septum, which provides a potentially new treatment option for HOCM.

A novel in vitro model of clinical cryoablation to investigate the transition zone for focal tumor ablation.

Cryoablation (CA) of solid tumors is highly effective at reducing tumor burden and eliminating small, early stage tumors. However, complete ablation is difficult to achieve and cancer recurrence is a significant barrier to treatment of larger tumors compared to resection. In this study, we explored the relationship between temperature, ice growth, and cell death using a novel in vitro model of clinical CA with the Visual-ICE (Boston Scientific) system, a clinically approved and widely utilized device. We found that increasing the duration of freezing from 1 to 2 min increased ice radius from 3.44 ± 0.13 mm to 5.29 ± 0.16 mm, and decreased the minimum temperature achieved from -22.8 ± 1.3 °C to -45.5 ± 7.9 °C. Furthermore, an additional minute of freezing increased the amount of cell death within a 5 mm radius from 42.5 ± 8.9% to 84.8 ± 1.1%. Freezing at 100% intensity leads to faster temperature drops and a higher level of cell death in the TRAMP-C2 mouse prostate cancer cell line, while lower intensities are useful for slow freezing, but result in less cell death. The width of transition zone between live and dead cells decreased by 0.4 ± 0.2 mm, increasing from one to two cycles of freeze/thaw cycles at 100% intensity. HMGB-1 levels significantly increased with 3 cycles of freeze/thaw compared to the standard 2 cycles. Overall, a longer freezing duration, higher freezing intensity, and more freeze thaw cycles led to higher levels of cancer cell death and smaller transition zones. These results have the potential to inform future preclinical research and to improve therapeutic combinations with CA.

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.

Biopsy Assessment of Oncologic Control 3 Years Following Primary Partial Gland Cryoablation: A Prospective Cohort Study of Men With Intermediate-risk Prostate Cancer.

PURPOSE: We evaluated 3-year oncologic outcomes following primary partial gland cryoablation. MATERIALS AND METHODS: Men with unilateral intermediate-risk prostate cancer undergoing primary partial gland cryoablation since March 2017 enrolled in a prospective outcome registry. The postablation protocol for all men included surveillance prostate biopsy at 2 years postablation and reflex prostate biopsy for cases with high suspicion of recurrence (eg, progressive rise in PSA). Recurrence of clinically significant prostate cancer was defined as any Gleason grade group ≥2 disease on postablation biopsy. Freedom from failure represented no whole gland salvage treatment, metastatic prostate cancer, or prostate cancer mortality. Freedom from recurrence and freedom from failure were characterized using nonparametric maximum likelihood estimators. RESULTS: A total of 132 men had at least 24 months of follow-up data. Biopsies identified clinically significant prostate cancer in 12 men. At 36 months, model-estimated rates of freedom from recurrence of in-field, out-of-field, and overall clinically significant cancer were 97% (95% CI: 92-100), 87% (95% CI: 80-94), and 86% (95% CI: 78-93), respectively. The model-estimated proportion with freedom from failure at 36 months was 97% (95% CI: 93-100). CONCLUSIONS: The low in-field cancer detection rate at 3 years indicates successful ablation of localized cancers. Conversely, our observed out-of-field detection rate highlights the need for continued surveillance following partial gland cryoablation. Many of these recurrences exhibited very low volume of clinically significant disease below the detection threshold of multiparametric MRI, suggesting a limited role for multiparametric MRI in detecting clinically significant recurrences at 2 years. These findings emphasize the need for long-term surveillance and identification of predictors of clinically significant prostate cancer recurrences to guide biopsy timing.

Cancer-specific Mortality After Cryoablation vs Heat-based Thermal Ablation in T1a Renal Cell Carcinoma.

PURPOSE: Guidelines suggest less favorable cancer control outcomes for local tumor destruction in T1a renal cell carcinoma patients with tumor size 3.1-4 cm. We compared cancer-specific mortality between cryoablation vs heat-based thermal ablation in patients with tumor size 3.1-4 cm, as well as in patients with tumor size ≤3 cm. MATERIALS AND METHODS: Within the Surveillance, Epidemiology, and End Results database (2004-2018), we identified patients with clinical T1a stage renal cell carcinoma treated with cryoablation or heat-based thermal ablation. After up to 2:1 ratio propensity score matching between patients treated with cryoablation vs heat-based thermal ablation, we addressed cancer-specific mortality relying on competing risks regression models, adjusted for other-cause mortality and other covariates (age, tumor size, tumor grade, and histological subtype). RESULTS: Of 1,468 assessable patients with tumor size 3.1-4 cm, 1,080 vs 388 were treated with cryoablation vs heat-based thermal ablation, respectively. After up to 2:1 propensity score matching that resulted in 757 cryoablations vs 388 heat-based thermal ablations, in multivariable competing risks regression models, heat-based thermal ablation was associated with higher cancer-specific mortality (HR:2.02, P < .001), relative to cryoablation. Of 4,468 assessable patients with tumor size ≤3 cm, 3,354 vs 1,114 were treated with cryoablation vs heat-based thermal ablation, respectively. After up to 2:1 propensity score matching that resulted in 2,217 cryoablations vs 1,114 heat-based thermal ablations, in multivariable competing risks regression models, heat-based thermal ablation was not associated with higher cancer-specific mortality (HR:1.13, P = .5) relative to cryoablation. CONCLUSIONS: Our findings corroborated that in cT1a patients with tumor size 3.1-4 cm, cancer-specific mortality is twofold higher after heat-based thermal ablation vs cryoablation. Conversely, in patients with tumor size ≤3 cm either ablation technique is equally valid. These findings should be considered at clinical decision making and informed consent.

Focal Therapy for Prostate Cancer: Evolutionary Parallels to Breast Cancer Treatment.

PURPOSE: Our goal was to review the history of the adoption of focal therapy for breast and prostate cancer and review common barriers to implementation. MATERIALS AND METHODS: A narrative review of the literature was performed of English-language MEDLINE indexed articles of breast-conservation therapy and prostate cancer focal therapy. RESULTS: The introduction of focal therapy in breast cancer began with pioneering case series, and multiple randomized trials were performed prior to widespread adoption. Focal therapy for prostate cancer has just started the process of clinical trials with a single published randomized controlled trial. Commonly cited barriers to the adoption of prostate focal therapy include historical views of Halstedian tumor biology, tumor multifocality, over-detection, limitations in prostate imaging, and trial design end points. CONCLUSIONS: The adoption of breast-conserving therapy evolved over decades and used data from multiple large, randomized, clinical trials. Barriers to the adoption of prostate cancer local therapy are similar to those faced by breast cancer clinical trials. Completion of well-designed trials in prostate cancer focal therapy is essential for its evidence-based adoption.

Cost-effectiveness of minimally invasive partial nephrectomy and percutaneous cryoablation for cT1a renal cell carcinoma.

BACKGROUND: There is growing evidence that partial nephrectomy (PN) and percutaneous cryoablation (PCA) yield comparable outcomes for patients with cT1a renal cell carcinoma (RCC), although the cost-effectiveness of both treatments still needs to be assessed. PURPOSE: To perform a cost-effectiveness analysis of PN and PCA for patients with cT1a RCC. MATERIALS AND METHODS: A decision analysis was created over a 5-year span from a healthcare payer's perspective computing expected costs and outcomes of PN and PCA in terms of quality-adjusted life-years (QALYs) and incremental cost-effectiveness (ICER). After each treatment, the following states were modelled using data from the recent literature: procedural complications, no evidence of disease (NED), local recurrence, metastases, and death from RCC- or non-RCC-related causes. Probabilistic and deterministic sensitivity analyses were performed. RESULTS: PCA and PN yielded health benefits of 3.68 QALY and 3.67 QALY. Overall expected costs were $20,491 and $26,478 for PCA and PN. On probabilistic sensitivity analysis, PCA was more cost-effective than PN in 84.78% of Monte Carlo simulations. PCA was more cost-effective until its complication risk was at least 38% higher than PN. PCA was more cost-effective than PN when (i) PCAs annual local recurrence risk was < 3.5% higher than that of PN in absolute values; (ii) PCAs annual metastatic risk was < 1.0% higher than that of PN; or (iii) PCAs annual cancer-specific mortality risk < 0.65% higher than that of PN. PCA remained cost-effective until its procedural cost is above $13,875. CONCLUSION: PCA appears to be more cost-effective than PN for the treatment of cT1a RCC, although the currently available evidence is of limited quality. PCA may be the better treatment strategy in the majority of scenarios varying procedural complications, recurrence, metastatic risk, and RCC-mortality in clinically plausible ranges. KEY POINTS: • For patients with cT1a RCCs, PCA yields a comparable health benefit at lower costs compared to PN, making PCA the dominant and therefore more cost-effective treatment strategy over PN. • PCA was more cost-effective than PN when (i) PCAs annual local recurrence risk was < 3.5% higher than PN in absolute values; (ii) PCAs annual metastatic risk was < 1.0% higher than PN; or (iii) PCAs annual cancer-specific mortality risk < 0.65% higher than PN. • PCA is more cost-effective than PN for the treatment of cT1a RCC, and it remained so in the majority of scenarios varying procedural complications, recurrence, metastatic risk, and RCC mortality.

Cryoablation is superior to radiofrequency ablation for the treatment of non-small cell lung cancer: A meta-analysis.

This meta-analytical study compared the efficacy of cryoablation and radiofrequency ablation (RFA) in treating non-small cell lung cancer (NSCLC). We searched PubMed, Cochrane, Embase, and Web of Science™ for all relevant articles published until April 2022 that compared the efficacy of RFA and cryoablation in treating NSCLC. We used the Cochrane evaluation tool to assess the risk of bias. The fixed- or random-effects models were used, when appropriate. The primary outcome was a 3-year disease-free survival, whereas recurrence rate and complication rates were secondary outcomes. There were 340 patients divided across the seven studies we included in our meta-analysis. Based on the continuous-type variable analysis, cryoablation was superior to RFA in terms of 3-year disease-free survival (P = 0.003) and complication (P ＜ 0.00001) rates. Similarly, significant reductions in cryoablation were found for recurrence rates (P = 0.05) compared with RFA. Overall, cryoablation was superior to RFA in terms of prognosis and lifespan, regardless of whether systemic metastases occurred in non-small cell lung cancer.

Suitable T stage for cryosurgery to spare the anus in patients with low rectal cancer.

Sphincter preserving therapy is a key research focus for treating low rectal cancer; however, the role of cryotherapy in this process has seldom been reported in the literature. Therefore, we conducted a comprehensive report on the role of cryoablation in sphincter preservation and explored its effect in rectal cancers. An observational study used longitudinal observation and follow-up. Participants were screened from patients whose medical records showed cryotherapy intervention for low rectal cancers from January 2016 to December 2020, with more than 2 years of follow-up. The primary endpoint was progress-free survival, and the secondary outcomes were mainly related to sphincter preservation rate and complications. Thirty-five patients were enrolled in this study, all of whom had their sphincters preserved. Until June 2022, 35 cases achieved long-term progression-free survival (41.77 ± 15.58), with no recurrence observed in 88.57% (31/35) of all patients at follow-up. Cryotherapy showed no significant differences in progress-free survival between sexes (p > 0.05). Cox regression was used to analyze the factors affecting local recurrence, with sex, T stage, size, and cryo-time taken as covariates. The results showed that T stage was a risk factor for local recurrence (p = 0.01, odds ratio: 16.27, 95% confidence interval: 8.20,145.75). Analysis of the T stage according to different subgroups showed that T3 stage was an independent risk factor (p = 0.002). We observed seven cases of complications, which were classified into grades I-II. In patients with low rectal cancers, cryotherapy can safely and effectively preserve the anus and avoid low anterior resection syndrome. Cryoablation has a better curative effect on radical treatment, especially for tumors in the T0-2 N0M0 stage.

Percutaneous treatment of chest wall chondroid hamartomas: the experience of a single center.

BACKGROUND: Thoracic mesenchymal hamartomas are rare benign lesions. Rarely symptomatic, they may compress pulmonary parenchyma, leading to respiratory distress. Although spontaneous regression has been documented, the more common outcome is progressive growth. The treatment of choice is en bloc excision of the involved portion of the chest wall, frequently leading to significant deformity. OBJECTIVE: The aim of our study was to describe percutaneous techniques to treat these lesions. MATERIALS AND METHODS: We collected data of children with thoracic mesenchymal hamartomas who were treated at our institution from 2005 to 2020 using various percutaneous techniques. Techniques included radiofrequency thermoablation, microwave thermoablation (microwave thermoablation) and cryoablation. RESULTS: Five children were treated for chest wall hamartomas; one child showed bilateral localization of the mass. Two children underwent microwave thermoablation, one radiofrequency thermoablation and two cryoablation; one child treated with cryoablation also had radiofrequency thermoablation because mass volume increased after the cryoablation procedure. The median reduction of tumor volume was 69.6% (24.0-96.5%). One child treated with microwave thermoablation showed volumetric increase of the mass and underwent surgical removal of the tumor. No major complication was reported. CONCLUSION: Percutaneous ablation is technically feasible for expert radiologists and might represent a valid and less invasive treatment for chest wall chondroid hamartoma, avoiding skeletal deformities.

Complications of Percutaneous Cryoablation for Renal Tumors and Methods for Avoiding Them.

Percutaneous cryoablation of renal tumors is widely used because of its high efficacy and safety. This high safety can be attributed, at least in part, to the visibility of the ablated area as an "ice ball". This therapy has fewer complications (incidence, 0-7.2%) and is less invasive than surgery. Minor bleeding is inevitable in most kidney-related procedures, and indeed the most common complication of this therapy is bleeding (hematoma and hematuria). However, patients require treatment such as transfusion or transarterial embolization in only 0-4% of bleeding cases. Various other complications such as ureteral or collecting system injury, bowel injury, nerve injury, skin injury, infection, pneumothorax, and tract seeding also occur, but they are usually minor and asymptomatic. However, operators should know and avoid the various complications associated with this therapy. This study aimed to summarize the complications of percutaneous cryoablation for renal tumors and provide some techniques for achieving safe procedures.

A Fiber Optic Sensor for Monitoring the Spectral Alterations and Depth in Ex Vivo and In Vivo Cryosurgery.

This article discusses how to monitor the freezing depth during cryotherapy using a fiber optic array sensor. The sensor was used to measure the backscattered and transmitted light from frozen and unfrozen ex vivo porcine tissue and in vivo human skin tissue (finger). The technique exploited the variations in optical diffusion properties of the frozen and unfrozen tissues to determine the extent of freezing. Ex vivo and in vivo measurements yielded comparable results, despite spectral variations attributable to the hemoglobin absorption peak in the human frozen and unfrozen tissues. However, because the spectral fingerprints of the freeze-thaw process in the ex vivo and in vivo experiments were similar, we could extrapolate the maximum depth of freezing. Therefore, this sensor has the potential to be utilized for monitoring cryosurgery in real time.

Numerical Simulation of bio-heat transfer for cryoablation of regularly shaped tumours in liver tissue using multiprobes.

The present study focuses upon pre-operative planning strategy for cryosurgical treatment of multiple regularly shaped tumours inside a three dimensional liver tissue. Numerical simulations provide an optimal framework to predict the number of cryo-probes, their placement, operation time and thermal necrosis to the tumour and surrounding healthy tissues. An efficient cryosurgery process requires keeping the tumour cell under lethal temperature which is between -40 °C to -50 °C. The freezing process of undesired tumour tissues involves phase transition from liquid phase to solid phase, the accurate capturing of transition front and size or location of ice balls generated in the process are the important factors of cryosurgery. In this study, fixed domain heat capacity method has been utilized to take into account the latent heat of phase change in bio-heat transfer equation. The ice balls generated with different number of probes haven been analysed. Numerical simulations have been carried out using standard Finite Element Method with COMSOL 5.5 and results obtained are validated with previous studies.

Percutaneous Management of Breast Cancer: a Systematic Review.

PURPOSE OF REVIEW: Surgical treatment of breast cancer is becoming increasingly more minimally invasive. We review the development status of percutaneous management for primary breast cancer and the evidence relating to tumor size as a fundamental determinant of treatment clinical outcome. RECENT FINDINGS: It is safe and feasible for percutaneous management to treat breast cancer. For tumor size ≤ 2 cm, percutaneous management is a promising alternative modality. For tumor size ≤ 3 cm, it is controversial whether percutaneous management can achieve similar effects to surgery, especially its long-term effects. For tumor size > 3 cm, it is still in the initial exploration stage and showed the potential in the treatment of unresectable cancer by benefitting the local control of primary cancer. Percutaneous management of breast cancer is a valuable method for breast cancer treatment in selected patients. However, it will be necessary to provide the high level of evidence for widespread clinical application.

Split-face comparative trial of 785-nm picosecond neodymium:yttrium-aluminum-garnet laser and precision cryotherapy combination treatment for facial benign pigmented lesions.

Cryotherapy (or cryosurgery) has been performed to treat various skin lesions in the field of dermatology; however, to the best of our knowledge, no study has investigated its efficacy and safety for benign pigmented lesions. Therefore, we conducted a split-face study to evaluate the efficacy and safety of cryotherapy in the treatment of benign pigmented lesions. A total of five subjects were included. Picosecond laser therapy was performed to treat the whole face and cryotherapy for half the face. Four weeks after completing the treatment sessions, patients showed more clinical improvement on the laser and cryotherapy combination treatment side than on the laser-only side, with no adverse events. Our study demonstrated that cryotherapy is a potential adjuvant therapeutic modality for benign pigmented lesions.

Immunocryosurgery is a safe and feasible treatment for basal cell carcinoma and Bowen disease in renal transplant recipients.

Keratinocyte skin carcinomas (squamous cell carcinoma, basal cell carcinoma [BCC], Bowen disease [BD]) inflict significant morbidity and constitute a treatment challenge in renal transplant recipients (RTR). Immunocryosurgery has shown efficacy >95% in the treatment of BCC and BD in immunocompetent patients. The present study evaluated the safety, feasibility and efficacy, of immunocryosurgery in the treatment of BCC and BD in a series of RTR. During a 3-year period, biopsy-confirmed cases of BCC and BD were treated with a standard immunocryosurgery cycle (5 weeks daily imiquimod and a session of cryosurgery at day 14). Safety was evaluated by comparing graft function markers between immunocryosurgery treated RTR patients and matched controls. Ten BCC (8 nodular, 1 basosquamous, 1 superficial; diameter 6-14 mm; mean 9.2 mm) and nine BD disease lesions in nine patients (7 men, 2 women; age range: 54-70 years, mean: 62.1 years) were treated with immunocryosurgery and followed-up for two to 5 years. Five BCC were located on the "H area" of the face. No patient showed clinical or laboratory signs of transplant dysfunction during treatment or follow-up. Seven out of 10 BCC lesions cleared completely after one 5-week immunocryosurgery cycle, two cleared after repeat and intensified treatment cycles and one responded only partially (clearance rate: 90%). Seven out of nine BD lesions cleared after one 5-week immunocryosurgery cycle and one lesion after two cycles (clearance rate: 88.9%). In conclusion, immunocryosurgery is a safe, feasible and effective minimally invasive treatment alternative to standard surgical modalities for BCC and BD in RTR.

Different Types of Auricular Keloids and Treatment by Intralesional Cryosurgery: Best Practice for Obtaining Long-Lasting Clinical Results.

BACKGROUND: Auricular keloids belong to the most perplexing medical conditions, which have significant psychosocial impact on the patient's body image and quality of life. SUMMARY: The article is purposed to provide dermatologists and plastic surgeons with the best proven practice using intralesional cryosurgery for the treatment of the different auricular keloid types in order to obtain superior clinical results by minimizing the probability of recurrence. In the past 20 years, the authors have developed novel procedures in order to increase the effectiveness of intralesional cryosurgery on auricular keloids, including hydrodissection, warm gauze technique, and excision of dangling skin. Long-lasting clinical results with a low recurrence rate and a satisfactory aesthetic outcome are achieved with no deformation of the ear framework.

A study of prostate multiprobe cryoablation near urethra for precision treatment planning.

The simplified preoperative planning of multiprobe prostate cryoablation limits its efficiency. In order to improve it, the thermal history prediction software is being developed. However, the problem of high risks at the prostate-urethra boundary has not been solved yet. The urethral warming system is used to protect the urethral canal from freezing. On the one hand it is used to reduce the risk of damage to the urethra; on the other hand it increases the risk of insufficient ablation of the tumor. This paper presents a step towards the possibility of carrying out the precision prostate cryoablation in this region. For the experimental part, three cases of arrangement of one and two argon cryoprobes and a heating catheter have been considered. Freezing zone shape and dimensions, and temperature at control points depending on time have been obtained. Experimental results have clearly shown the effect of the heating catheter, the second cryoprobe, and the initial temperature of the biotissue phantom on the freezing zone. After, the thermal aspects of treatment simulation have been developed and verified. A series of calculations have been carried out with the goal to get the information about optimizing the prostate cryoablation on the prostate-urethra boundary. The arrangement of cryoprobes has been proposed for three different variants for prostate cryoablation (sectors of 90, 180° and 360°). The area of prostate tissues near the urethra that cannot be cooled below the necrosis temperature is shown. This information is expected to be useful for improving the quality of cryosurgery planning algorithms (e.g. for tumor treatment).

Ulvan-Based Nanofibrous Patches Enhance Wound Healing of Skin Trauma Resulting from Cryosurgical Treatment of Keloids.

Keloids are skin fibroproliferative disorders, resulting from abnormal healing of deep cutaneous injuries. Cryosurgery, the most common treatment for keloids, causes skin traumas. Even though the clinical practice of cryosurgery has increased, effective wound healing therapy is still lacking. In this investigation, nonwoven nanofibrous patches composed of ulvan, a marine sulfated polysaccharide exhibiting anti-inflammatory and antioxidant activities, and polyethylene oxide (PEO) were fabricated through electrospinning and characterized. Their wound healing efficacy on skin traumas resulting from cryosurgical treatment of keloids was clinically tested and evaluated in comparison to a reference product. Twenty-four volunteer patients undergoing cryosurgery as a treatment of keloids were selected to apply either the ulvan/PEO patch or the reference product for 21 days. The ulvan/PEO patch, 21 days after cryosurgery, showed significant wound healing, elimination of skin inflammation, restoration of biophysical parameters similar to normal values and significant decrease in haemoglobin concentration, skin texture and volume, while no discomfort or adverse reaction was observed. In contrast, the reference product showed inferior performance in all evaluated parameters. The designed ulvan/PEO patch represents the first wound dressing to effectively heal skin trauma after cryosurgical treatment of keloids.