Ablation Of Prostate Cancer Research Articles

Perceptions of partial gland ablation for prostate cancer among men on active surveillance: a qualitative study

ObjectivesPartial gland ablation (PGA) therapy is an emerging treatment modality that targets specific areas of biopsy-proven prostate cancer (PCa) to minimize treatment-related morbidity by sparing benign prostate. This qualitative study...

Focal Laser Ablation of Prostate Cancer: An Office Procedure

In this article, we describe and illustrate an outpatient procedure for focal laser ablation (FLA) of prostate cancer (PCa). The procedure is conceptually similar to a fusion biopsy and is performed under local anesthesia in a clinic setting; treatment time is usually less than one hour. Laser insertion is guided by ultrasound; lesion targeting is via magnetic resonance imaging-ultrasound (MRI/US) fusion, as in targeted prostate biopsy. Real-time ablation monitoring is achieved utilizing a thermal probe adjacent to the laser fiber. The video demonstrates procedure planning, patient preparation, various steps during the procedure, and treatment monitoring. Safety, feasibility, and efficacy of this approach have been established during a previous trial. Outpatient FLA under local anesthesia is an option for management of intermediate risk prostate cancer.

Focal Laser Ablation of Prostate Cancer: An Office Procedure.

In this article, we describe and illustrate an outpatient procedure for focal laser ablation (FLA) of prostate cancer (PCa). The procedure is conceptually similar to a fusion biopsy and is performed under local anesthesia in a clinic setting; treatment time is usually less than one hour. Laser insertion is guided by ultrasound; lesion targeting is via magnetic resonance imaging-ultrasound (MRI/US) fusion, as in targeted prostate biopsy. Real-time ablation monitoring is achieved utilizing a thermal probe adjacent to the laser fiber. The video demonstrates procedure planning, patient preparation, various steps during the procedure, and treatment monitoring. Safety, feasibility, and efficacy of this approach have been established during a previous trial. Outpatient FLA under local anesthesia is an option for management of intermediate risk prostate cancer.

This Month in Adult Urology

This Month in Adult Urology

MR-Guided High-Intensity Directional Ultrasound Ablation of Prostate Cancer

The goal of this paper was to review the novel treatment modality of high-intensity transurethral directional ultrasound for prostate cancer. Prostate cancer is a heterogeneous disease with some patients electing for active surveillance and focal therapies instead of definitive treatment with radical prostatectomy or radiation therapy. Prostate MRI has become a cornerstone of prostate cancer diagnosis, targeted biopsy, and treatment planning. Transurethral high-intensity directional ultrasound allows for MRI-guided ablation of the prostate gland with the ability to contour boundaries and spare critical structures, such as the neurovascular bundle and urinary sphincter. Although results are still emerging, this may offer patients a new option for focal therapy with a favorable side-effect profile. High-intensity transurethral directional ultrasound is an emerging treatment modality for both whole-gland and focal ablation with promising early results. Further research is needed to establish safety, tolerability, and long-term oncologic outcomes.

Re: High Intensity Focused Ultrasound Hemigland Ablation for Prostate Cancer. Initial Outcomes of a United States Series

Re: High Intensity Focused Ultrasound Hemigland Ablation for Prostate Cancer. Initial Outcomes of a United States Series

Acute and subacute prostate MRI findings after MRI-guided transurethral ultrasound ablation of prostate cancer.

Magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) is an emerging method for treatment of localized prostate cancer (PCa). TULSA-related subacute MRI findings have not been previously characterized. To evaluate acute and subacute MRI findings after TULSA treatment in a treat-and-resect setting. Six men with newly diagnosed MRI-visible and biopsy-concordant clinically significant PCa were enrolled and completed the study. Eight lesions classified as PI-RADS 3-5 were focally ablated using TULSA. One- and three-week follow-up MRI scans were performed between TULSA and robot-assisted laparoscopic prostatectomy. TULSA-related hemorrhage was detected as a subtle T1 hyperintensity and more apparent T2 hypointensity in the MRI. Both prostate volume and non-perfused volume (NPV) markedly increased after TULSA at one week and three weeks after treatment, respectively. Lesion apparent diffusion coefficient values increased one week after treatment and decreased nearing the baseline values at the three-week MRI follow-up. The optimal timing of MRI follow-up seems to be at the earliest at three weeks after treatment, when the post-procedural edema has decreased and the NPV has matured. Diffusion-weighted imaging has little or no added diagnostic value in the subacute setting.

P049 - PSA changes after laser ablation of prostate cancer and its relation with the extent of the thermal damage on the malignant tissue

P049 - PSA changes after laser ablation of prostate cancer and its relation with the extent of the thermal damage on the malignant tissue

High Intensity Focused Ultrasound Hemigland Ablation for Prostate Cancer: Initial Outcomes of a United States Series.

We report outcomes of hemigland high intensity focused ultrasound ablation as primary treatment for localized prostate cancer in the United States. A total of 100 consecutive men underwent hemigland high intensity focused ultrasound (December 2015 to December 2019). Primary end point was treatment failure, defined as Grade Group 2 or greater on followup prostate biopsy, radical treatment, systemic therapy, metastases or prostate cancer specific mortality. IIEF (International Index of Erectile Function), I-PSS (International Prostate Symptom Score) and 90-day complications were reported. At study entry patients had very low (8%), low (20%), intermediate favorable (50%), intermediate unfavorable (17%) and high (5%) risk prostate cancer. Median followup was 20 months. The 2-year survival free from treatment failure, Grade Group 2 or greater recurrence, repeat focal high intensity focused ultrasound and radical treatment was 73%, 76%, 90% and 91%, respectively. Bilateral prostate cancer at diagnosis was the sole predictor for Grade Group 2 or greater recurrence (p=0.03). Of men who underwent posttreatment biopsy (58), 10 had in-field and 8 out-of-field Grade Group 2 or greater positive biopsy. Continence (zero pad) was maintained in 100% of patients. Median IIEF-5 and I-PSS scores before vs after hemigland high intensity focused ultrasound were 22 vs 21 (p=0.99) and 9 vs 6 (p=0.005), respectively. Minor and major complications occurred in 13% and 0% of patients. No patient had rectal fistula or died. Short-term results of focal high intensity focused ultrasound indicate safety, excellent potency and continence preservation, and adequate short-term prostate cancer control. Radical treatment was avoided in 91% of men at 2 years. Men with bilateral prostate cancer at diagnosis have increased risk for Grade Group 2 or greater recurrence. To our knowledge, this is the initial and largest United States series of focal high intensity focused ultrasound as primary treatment for prostate cancer.

885 - Hemi-gland high intensity focus ultrasound ablation for prostate cancer: Short-term outcomes from one of the largest US series

885 - Hemi-gland high intensity focus ultrasound ablation for prostate cancer: Short-term outcomes from one of the largest US series

V022 - Transperineal microwave ablation of prostate cancer guided by MRI ultrasound fusion and organ based tracking technology

V022 - Transperineal microwave ablation of prostate cancer guided by MRI ultrasound fusion and organ based tracking technology

Prospective Feasibility Study of Single-Shot Antibiotic Prophylaxis in Transrectal Focal Ablation of Prostate Cancer

Introduction: Urinary tract infections (UTI) represent the most frequent complications after transrectal focal ablation of prostate cancer. Single-shot antibiotic prophylaxis for prevention has not yet been described. Methods: In this cohort study of patients who received a high-intensity focused ultrasound (HIFU) ablation of prostate cancer within a registered prospective single-arm trial, we analyzed posttreatment UTI (≤30 days after HIFU) related to perioperative antibiotic management in an exploratory analysis: single-shot prophylaxis or targeted treatment for bacteriuria. Potential risk factors associated with UTI were evaluated by uni- and multivariate regression analyses. Results: In total, 55 patients were eligible for analysis. Of these, 76.4% received antibiotic single-shot prophylaxis. UTI occurred in 10.7% of all patients, 5.4% developed fever, 3.6% required hospitalization. An antibiotic single-shot prophylaxis helped to protect 90.5% of men from infectious complications. Estimated effects indicate that a longer posttreatment catheterization (OR 3.38, 95% CI 0.47–27.08) and larger ablation volume (OR 4.85, 95% CI 0.61–107.49) might be associated with the highest risk for UTI after treatment. Conclusion: Single-shot antibiotic prophylaxis compared to a targeted antibiotic treatment showed a similar effectivity to prevent patients from infectious complications and should be considered as an element of antibiotic stewardship. Further research on risk factors and antibiotic strategies is required.

MP70-14 PROSPECTIVE TRIAL OF REGIONAL (HOCKEY-STICK) PROSTATE CRYOABLATION: 7-YEAR PATHOLOGIC AND QUALITY OF LIFE OUTCOMES

You have accessJournal of UrologyProstate Cancer: Localized: Ablative Therapy II (MP70)1 Apr 2020MP70-14 PROSPECTIVE TRIAL OF REGIONAL (HOCKEY-STICK) PROSTATE CRYOABLATION: 7-YEAR PATHOLOGIC AND QUALITY OF LIFE OUTCOMES Leonardo Borregales*, Justin Gregg, Haesun Choi, Marisa Lozano, Stephen McRae, Aradhana Venkatesan, Graciela Nogueras Gonzalez, John Davis, Louis Pisters, and John Ward Leonardo Borregales*Leonardo Borregales* More articles by this author , Justin GreggJustin Gregg More articles by this author , Haesun ChoiHaesun Choi More articles by this author , Marisa LozanoMarisa Lozano More articles by this author , Stephen McRaeStephen McRae More articles by this author , Aradhana VenkatesanAradhana Venkatesan More articles by this author , Graciela Nogueras GonzalezGraciela Nogueras Gonzalez More articles by this author , John DavisJohn Davis More articles by this author , Louis PistersLouis Pisters More articles by this author , and John WardJohn Ward More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000950.014AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Organ preserving therapies are of particular interest in the treatment of localized prostate cancer (PC) with a goal of decreasing morbidity associated with radical treatment while maintaining oncologic control. With the development of Index Tumor theory of PC in parallel with improved ablative technology, regional ablation of PC has become an intriguing concept. We report long term follow-up of a prospective clinical trial of subtotal prostate ablation (hockey-stick template), including oncologic efficacy and quality of life (QoL) impact. METHODS: Men with low and intermediate risk PC by systematic diagnostic biopsy was performed. All men underwent confirmatory 12-core, extended scheme biopsy using robotic assistance to eliminate user bias, standardize the biopsy across the study’s time course and minimize sampling bias. Men were eligible to proceed with regional cryoablation if confirmatory biopsy revealed grade group (GG) 1 or 2 disease in fewer than 50% of unilateral cores and no more than 50% involvement of any single core. Contralateral GG1 with <2mm involvement was also eligible. EPIC QoL questionnaires were completed prior to confirmatory biopsy and at each follow-up visit. Prostate biopsies were performed in a similar fashion at 6, 18 and 36 months following regional ablation, and follow-up was updated to include subsequent visits. RESULTS: Between August 2009 and January 2012, 72 men were screened for trial eligibility and 47 underwent confirmatory biopsy, of whom 23 were treated with regional cryoablation. Median age at the time of treatment was 63 years. A single patient had <1mm of in-field tumor with therapy effect on 36 month biopsy. Total median follow-up was 74 months.During this time, new out-of field GG1 cancer was discovered on subsequent biopsies in 9 patients. Out of these, 1 patient opted for radiation therapy, 1 patient underwent re-do cryoablation while 7 others continued on active surveillance without subsequent GG increase. A total of 12 (52%) patients did not have evidence of disease, all patients had preserved urinary control with 0% of patients requiring pads for incontinence and sexual function decline was less than 20% of baseline. CONCLUSIONS: Focal (hockey-stick template) cryoablation of the prostate provides excellent oncologic efficacy to targeted tissue with minimal impact on sexual and urinary function in well selected patients. This feasibility study can be used to justify further investigations into organ preserving PC ablative techniques using improved imaging and a variety of thermal energy sources. Source of Funding: none © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e1060-e1060 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Leonardo Borregales* More articles by this author Justin Gregg More articles by this author Haesun Choi More articles by this author Marisa Lozano More articles by this author Stephen McRae More articles by this author Aradhana Venkatesan More articles by this author Graciela Nogueras Gonzalez More articles by this author John Davis More articles by this author Louis Pisters More articles by this author John Ward More articles by this author Expand All Advertisement PDF downloadLoading ...

V14-03 TRANSPERINEAL MICROWAVE NEEDLE THERMOABLATION OF PROSTATE CANCER GUIDED BY MRI ULTRASOUND FUSION AND ORGAN BASED TRACKING TECHNOLOGY

You have accessJournal of UrologyProstate Cancer (V14)1 Apr 2020V14-03 TRANSPERINEAL MICROWAVE NEEDLE THERMOABLATION OF PROSTATE CANCER GUIDED BY MRI ULTRASOUND FUSION AND ORGAN BASED TRACKING TECHNOLOGY Peter Ka-Fung Chiu*, Jeremy Yuen-Chun Teoh, Sui Yan Lau, Chi Hang Yee, Ka Lun Lo, Kai Man Li, Suk Yin Li, Sze Wan Kwok, Chi Kwok Chan, See Ming Hou, Carmen Chi Min Cho, and Chi Fai Ng Peter Ka-Fung Chiu*Peter Ka-Fung Chiu* More articles by this author , Jeremy Yuen-Chun TeohJeremy Yuen-Chun Teoh More articles by this author , Sui Yan LauSui Yan Lau More articles by this author , Chi Hang YeeChi Hang Yee More articles by this author , Ka Lun LoKa Lun Lo More articles by this author , Kai Man LiKai Man Li More articles by this author , Suk Yin LiSuk Yin Li More articles by this author , Sze Wan KwokSze Wan Kwok More articles by this author , Chi Kwok ChanChi Kwok Chan More articles by this author , See Ming HouSee Ming Hou More articles by this author , Carmen Chi Min ChoCarmen Chi Min Cho More articles by this author , and Chi Fai NgChi Fai Ng More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000982.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The objective of this video is to show the technique of a novel transperineal microwave needle thermoablation of localized prostate cancer (PCa) guided by MRI-Ultrasound fusion and Organ-based tracking (OBT) technology. METHODS: The case was an obese 70 year-old man with history of diabetes, hypertension, hyperlipidemia, and radiological cerebral infarcts without symptom. He has excellent performance status. His PSA was 5.7 ng/mL and Prostate Health Index (PHI) was 42.8. MRI prostate showed a 15x10 mm PI-RADS 5 lesion at left anterior transitional zone in a 35ml prostate without extra-capsular extension. Transperineal MRI-Ultrasound fusion biopsy of the target lesion showed Gleason 3+3 PCa in all 3 cores with 70% core involvement. 15 Systematic biopsy cores in other sectors were all benign. Focal therapy using microwave needle ablation was planned. Before treatment, fleet enema and a dose of IV antibiotic was given. The patient received spinal anaesthesia and was placed in lithotomy position. The MRI images marked with the target lesion were displayed on the screen of the MRI-Ultrasound fusion machine. The 3D side-fire transrectal probe was inserted, positioned at prostate level and fixed with a probe holder. A full grid was applied to the probe. MRI and Ultrasound fusion was performed with automatic 3D ultrasound scanning and OBT technology to provide accurate prostate tracking and target localization. The expected ellipsoid treatment zones of multiple Microwave needle ablations were planned on screen. A 17G microwave needle was inserted at the planned path in the fullgrid and the exact needle position was confirmed with repeated 3D ultrasound scanning and OBT image fusion. In the current case, 3 sequential needle ablations (Two 5-minute and one 3-minute) at 12 Watts were done to cover the lesion with margin. The whole treatment including planning took 65 minutes. A Foley’s catheter was inserted at the end. RESULTS: The Foley’s catheter was removed the next day and he was discharged home. MRI prostate with contrast was repeated on day 12 and the necrotic foci correlated well with the planned ellipsoid ablation zones without residual tumor seen. Individual needle tracks were also visualized on MRI images. Microwave needle ablation therapy has so far been successfully performed in 3 patients and all tolerated the procedure well. CONCLUSIONS: Transperineal microwave needle ablation of prostate cancer can be precisely and safely performed under the guidance of MRI-Ultrasound fusion and Organ based tracking. Source of Funding: None © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e1306-e1307 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Peter Ka-Fung Chiu* More articles by this author Jeremy Yuen-Chun Teoh More articles by this author Sui Yan Lau More articles by this author Chi Hang Yee More articles by this author Ka Lun Lo More articles by this author Kai Man Li More articles by this author Suk Yin Li More articles by this author Sze Wan Kwok More articles by this author Chi Kwok Chan More articles by this author See Ming Hou More articles by this author Carmen Chi Min Cho More articles by this author Chi Fai Ng More articles by this author Expand All Advertisement PDF downloadLoading ...

Abstract No. 468 Cost analysis of focal laser ablation for prostate cancer: in magnetic resonance imaging versus transrectal ultrasound fusion guidance outside magnetic resonance imaging

Abstract No. 468 Cost analysis of focal laser ablation for prostate cancer: in magnetic resonance imaging versus transrectal ultrasound fusion guidance outside magnetic resonance imaging

The changing role of lasers in urologic surgery.

To summarize recent publications on the topic of laser in urology and explore new developments which may impact the future role of lasers in surgery. Ho: Yttrium-aluminium garnet (YAG) laser with Moses technology allows less retropulsion during a lithotripsy, yet its efficacy needs to be tested in clinical trials. Data on the efficacy of this device for benign prostatic obstruction treatment is also pending. A new promising generation of laser systems - thulium-fiber (Tm-fiber) lasers - has been introduced. Tm-fiber has already been shown to be effective and well tolerated in endoscopic enucleation of the prostate and has demonstrated favorable outcome compared with Ho:YAG in preclinical lithotripsy studies. However, more studies are needed to better understand the use of this novel technology and elucidate its role within the armamentarium of available technologies. Lasers remain an integral part of benign prostatic hyperplasia surgery and stone treatment and gain popularity in en-bloc resection of bladder cancer. Current efficacy of laser systems in prostate cancer ablation and their place in laparoscopy remain unclear, despite promising initial reports.

Using spatial tracking with magnetic resonance imaging/ultrasound-guided biopsy to identify unilateral prostate cancer.

To create reliable predictive metrics of unilateral disease using spatial tracking from a fusion device, thereby improving patient selection for hemi-gland ablation of prostate cancer. We identified patients who received magnetic resonance imaging (MRI)/ultrasound-guided biopsy and radical prostatectomy at a single institution between 2011 and 2018. In addition to standard clinical features, we extracted quantitative features related to biopsy core and MRI target locations predictive of tumour unilaterality. Classification and Regression Tree (CART) analysis was used to create a decision tree (DT) for identifying cancer laterality. We evaluated concordance of model-determined laterality with final surgical pathology. A total of 173 patients were identified with biopsy coordinates and surgical pathology available. Based on CART analysis, in addition to biopsy- and MRI-confirmed disease unilaterality, patients should be further screened for cancer detected within 7mm of midline in a 40mL prostate, which equates to the central third of any-sized prostate by radius. The area under the curve for this DT was 0.82. Standard diagnostics and the DT correctly identified disease laterality in 73% and 80% of patients, respectively (P=0.13). Of the patients identified as unilateral by standard diagnostics, 47% had undetected contralateral disease or were otherwise incorrectly identified. This error rate was reduced to 17% (P=0.01) with the DT. Using spatial tracking from fusion devices, a DT was more reliable for identifying laterality of prostate cancer compared to standard diagnostics. Patients with cancer detected within the central third of the prostate by radius are poor hemi-gland ablation candidates due to the risk of midline extension of tumour.

Feasibility of MRI-guided transurethral ultrasound for lesion-targeted ablation of prostate cancer

Background: MRI-guided transurethral ultrasound ablation (TULSA) has been evaluated for organ-confined prostate cancer (PCa). The purpose of this study was to assess the safety and toxicity, accuracy and short-term evolution of cell-death after lesion-targeted TULSA.Methods: This prospective, registered, Phase-I treat-and-3-week-resect-study enrolled six patients with MRI-visible-biopsy-concordant PCa. Lesions were targeted using TULSA with radical intent, except near neurovascular bundles (NVB). Robot-assisted-laparoscopic-prostatectomy (RALP) was performed at 3 weeks. Post-TULSA assessments included MRI (1 and 3 weeks), adverse events and quality-of-life (QoL) to 3 weeks, followed by RALP and whole-mount-histology. Treatment accuracy and demarcation of thermal injury were assessed using MRI and histology.Results: Six patients (median age = 70 years, prostate volume = 60 ml, PSA = 8.9 ng/ml) with eight biopsy-confirmed MRI-lesions (PIRADS ≥3) were TULSA-treated without complications (median sonication and MRI-times of 17 and 117 min). Foley-catheter removal was uneventful at 2–3 days. Compared to baseline, no differences in QoL were noted at 3 weeks. During follow-up, MRI-derived non-perfused-volume covered ablated targets and increased 36% by 3 weeks, correlating with necrosis-area on histology. Mean histological demarcation between complete necrosis and outer-limit-of-thermal-injury was 1.7 ± 0.4 mm. Coagulation necrosis extended to capsule except near NVB, where 3 mm safety-margins were applied. RALPs were uncomplicated and histopathology showed no viable cancer within the ablated tumor-containing target.Conclusions: Lesion-targeted TULSA demonstrates accurate and safe ablation of PCa. A significant increase of post-TULSA non-perfused-volume was observed during 3 weeks follow-up concordant with necrosis on histology. TULSA achieved coagulation necrosis of all targeted tissues. A limitation of this treat-and-resect-study-design was conservative treatment near NVB in patients scheduled for RALP.

Irreversible Electroporation for the Ablation of Prostate Cancer.

Although still considered experimental, focal irreversible electroporation (IRE) as a primary treatment for prostate cancer (PCa) is considered one of the most promising ablative technologies for focal therapy. This review provides a description of the principle of IRE for the treatment of PCa, combined with an overview of the recent research. It has been almost a decade since the first human studies of focal IRE for PCa were trying to demonstrate its feasibility and safety, and recently new data are emerging regarding the functional and oncological outcomes. It was shown that the expected ablation efficacy of IRE is dependent on increased safety margins of > 9mm and an uninterrupted IRE procedure, but these findings need further investigation in larger cohorts and randomized control trials (RCT). Recent data from larger cohorts with a longer follow-up of up to 12months prove that focal IRE as primary treatment for localized PCa is indeed safe, has effective short-term oncological control in selected patients, and it has good functional outcomes by retaining urinary function and causing only mild erectile dysfunction.

Focused Ultrasound Effects on Osteosarcoma Cell Lines.

MRI guided Focused Ultrasound (MRgFUS) has shown to be effective therapeutic modality for non-invasive clinical interventions in ablating of uterine fibroids, in bone metastasis palliative treatments, and in breast, liver, and prostate cancer ablation. MRgFUS combines high intensity focused ultrasound (HIFU) with MRI images for treatment planning and real time thermometry monitoring, thus enabling non-invasive ablation of tumor tissue. Although in the literature there are several studies on the Ultrasound (US) effects on cell in culture, there is no systematic evidence of the biological effect of Magnetic Resonance guided Focused Ultrasound Surgery (MRgFUS) treatment on osteosarcoma cells, especially in lower dose regions, where tissues receive sub-lethal acoustic power. The effect of MRgFUS treatment at different levels of acoustic intensity (15.5-49 W/cm2) was investigated on Mg-63 and Saos-2 cell lines to evaluate the impact of the dissipation of acoustic energy delivered outside the focal area, in terms of cell viability and osteogenic differentiation at 24 h, 7 days, and 14 days after treatment. Results suggested that the attenuation of FUS acoustic intensities from the focal area (higher intensities) to the “far field” (lower intensities) zones might determine different osteosarcoma cell responses, which range from decrease of cell proliferation rates (from 49 W/cm2 to 38.9 W/cm2) to the selection of a subpopulation of heterogeneous and immature living cells (from 31.1 W/cm2 to 15.5 W/cm2), which can clearly preserve bone tumor cells.