Search

Neutrophil-to-lymphocyte ratio (NLR) recently demonstrated predictive value for hepatocellular carcinoma (HCC) recurrence after thermal ablation. Microwave ablation (MWA) has been shown to induce changes in the immune landscape after HCC treatment. This study aims at identifying predictors of local tumor progression (LTP) and post-treatment NLR kinetics after MWA.Data from 108 consecutive patients who underwent percutaneous MWA of 119 HCCs with a 2450 Hz/100 W generator in two institutions from October 2014 to September 2021 were retrospectively reviewed. Forty-five HCCs (42 patients) met inclusion criteria for analysis (technique efficacy, pre- and post-treatment NLR availability, follow-up 6 months, absence of complications). NLR was analyzed prior to therapy and at 1-month follow-up; difference between the two time points was defined as ΔNLRAfter a median follow-up of 25 months, LTP occurred in 18 HCCs (40%) and 18 patients (42.9%). Multivariate competing risk regression comprising ΔNLRNLR increase after ablation was the only independent predictor of LTP, supporting the role of balance between systemic inflammation and immunity in recurrence after MWA. Ablation energy/tumor size predicted NLR increase, reinforcing the concept of immune ablation.III.

ZusammenfassungDie Radiofrequenzablation ist ein effektives Verfahren, um benigne Schilddrüsenknoten bis zu einem Volumen von etwa 100 ml zu behandeln. Sie ist gut verträglich und kommt zurzeit − zusammen mit der Echopulstherapie − in Deutschland am häufigsten zur lokalen Therapie benigner Schilddrüsenknoten zum Einsatz. Insgesamt ist eine Volumenreduktion von etwa 50 % bis 70 % zu erwarten, bei zystischen Knoten und mixed-pattern-Läsionen etwas mehr als bei soliden Knoten. Anfangsvolumen, Struktur und Echogenität sind wichtige Parameter, welche die Effektivität beeinflussen. Es kommen bipolare und monopolare Verfahren zum Einsatz − die Auswahl des jeweiligen Verfahrens hängt v. a. von der persönlichen Präferenz des Behandelnden ab. Bei größeren Knoten wird eher die bipolare Technik angewendet. Gekühlte Systeme sind – insbesondere bei größeren Sonden – in jedem Fall vorzuziehen. Gravierendere Nebenwirkungen sind selten (

Objectives: Uterine fibroids (UF) are the most common benign tumors of the female reproductive organ. It is crucial to recognize that the appropriate treatment of UFs requires an individualized approach. The present paper aimed at the presentation of the five-year experience of our center in the treatment of UFs with the use of magnetic resonance-guided high-intensity ultrasound (MR-HIFU) therapy. Material and methods: The study enrolled a total of 1284 patients with symptomatic UFs. The Sonalleve MR-HIFU system (Philips Ingenia 3.0T System) was used for magnetic resonance imaging (MRI) qualification and treatment. Results: The group of patients qualified for thermal ablation included 356 (28%) women. No significant differences were observed between the group undergoing thermal ablation and patients who were disqualified. A complete procedure was performed in 22.6% of patients who presented at the center. Non-perfused volume (NPV) is one of the most important parameters assessed during MR-HIFU procedures. The mean NPV value in the present study was 71%. The average UF volumes decreased by 27% at three-month follow-up ultrasound, by 34% after six months and by 39% as shown by MRI measurements performed 6 months post-treatment. Conclusions: According to our data, MR-HIFU therapy is associated with good clinical outcomes in patients with symptomatic UFs. The method facilitates a marked symptom reduction and, in many cases, diminishing tumor volume. The presented five-year outcomes as regards our experience in the MR-HIFU therapy of patients with symptomatic UFs indicate that the method offers an attractive alternative to the traditional methods of UF treatment in selected cases.

One major challenge of photothermal therapy (PTT) is achieving thermal ablation of the tumor without damaging the normal cells and tissues. Here, we designed a self-regulating photothermal conversion system for selective thermotherapy based on self-assembling gold nanoparticles (S-AuNPs) and investigated the selectivity effect using a novel home-made in vitro selective photothermal transformation model and an in vivo skin damaging assessment model. In the in vitro selective photothermal transformation model, laser irradiation selectively increased the temperature of the internal microenvironment (pH 5.5) and resulted in an obvious temperature difference (ΔT ≥ 5 °C) with that of the external environment (pH 7.4). More importantly, in the in vivo skin damaging assessment model, S-AuNPs achieved good tumor inhibition without damaging the normal skin tissue compared with the conventional photothermal material. This work provides not only a novel validation protocol for tumor thermotherapy to achieve the biosafety of specifically killing tumor cells and normal tissue but also an evaluation methodology for other precise therapy for cancers.

Addendum to "Prospective observational evaluation of predictive models for thermal ablation outcomes of colorectal liver metastasis". This is a prospective evaluation of three radiomics-based prediction models for development of new intrahepatic metastasis following percutaneous thermal ablation of colorectal liver metastases. The study is for the same patient cohort as the original protocol.

INTRODUCTION Image-guided thermal ablation, preferably with ultrasonography (US), is increasingly used for treatment of small liver tumours. Perfluorobutane-contrast-enhanced US (pCEUS) is a promising tool that may allow for targeting of tumours that are otherwise imperceptible on greyscale US. Although pCEUS has been reported to be effective, the literature has been limited outside of Japan and South Korea. We aimed to provide data that supports the use of pCEUS in the thermal ablation of sonographically occult liver tumours. METHODS We conducted a retrospective single-centre study of 35 consecutive patients who underwent pCEUS-guided ablation of 48 liver tumours with a median size of 1.2 cm. Periprocedural, one-month post-treatment and relevant follow-up imaging studies were reviewed. Electronic records were also obtained, with long-term follow-up data of 12–28 months being available for 32 patients. RESULTS 36 (75%) tumours that were imperceptible on greyscale US became visible with pCEUS. Overall, complete tumour ablation at one month was 89%. 1 (3%) patient developed a major complication following treatment, while 6 (17%) had minor post-treatment complaints. The local tumour progression rate was 17%, with a median time of 14 months. CONCLUSION pCEUS has a role in US-guided thermal ablation of liver tumours, offering a high technical success rate that is comparable to reported data. Additional benefits may include improved procedural time and freedom from ionising radiation.

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver and has an overall five-year survival rate of less than twenty percent. For patients with unresectable disease, evolving liver-directed locoregional therapies provide efficacious treatment across the spectrum of disease stages and via a variety of catheter-directed and percutaneous techniques. Goals of locoregional therapies in HCC may include curative intent in early-stage disease, bridging or downstaging to surgical resection or transplantation for early or intermediate-stage disease, and local disease control and palliation in advanced-stage disease. This review explores the outcomes of chemoembolization, bland embolization, radioembolization, and percutaneous ablative therapies. Attention is also given to prognostic factors related to each of the respective techniques, as well as future directions of locoregional therapies for HCC.

Introduction:We assessed current utilization and sequencing of renal mass biopsy (RMB) and thermal ablation for renal cell carcinoma (RCC) patients in the United States.Methods:The 2004–201...

The outcomes of technically successful image-guided percutaneous thermal ablation of melanoma adrenal metastases involving 11 tumors in 9 consecutive patients over 12 years (2009–2020) were evaluated. All patients had multiple treated metastatic sites, and 44.4% (4/9) had greater than 5 metastatic sites. The mean maximal tumor diameter was 3.6 ± 1.6 cm. The local recurrence-free survival at 1 year was 85.7%. With a median survival of 19.4 months, 66.6% (6/9) of patients died from tumor progression. The 1- and 3-year overall survival rate was 60.0% and 30.0%, respectively. All patients were pretreated with alpha-adrenergic blockade, and 36% (4/11) developed a hypertensive crisis. The median hospital length of stay was 1 day (range, 1–2 days), without any major complications. Thermal ablation of adrenal metastasis from a melanoma provides acceptable local control and a good safety profile.

Please see the Editorial Comment by Joanna Kee-Sampson discussing this article. BACKGROUND. Transarterial chemoembolization (TACE) has synergistic properties when combined with ablative therapies f...

Surgical resection is the optimal treatment for HCC, despite a high risk of recurrence. Few data are available on patient’s survival after resection. This is a retrospective study of tumor recurrence occurring after hepatectomy for HCC from 2000 to 2016. Univariate and multivariate analyses were performed to identify prognostic factors of survival after recurrence (SAR). Among 387 patients, 226 recurred (58.4%) with a median SAR of 26 months. Curative treatments (liver transplantation, repeat hepatectomy, thermal ablation) were performed for 44.7% of patients. Independent prognostic factors for SAR were micro-vascular invasion on the primary surgical specimen, size of the initial tumor >5 cm, preoperative AFP, albumin and platelet levels, male gender, number, size and localization of tumors at recurrence, time to recurrence, Child–Pugh score and treatment at recurrence. In subgroup analysis, early recurrence (46%) was associated with a decrease in SAR, by contrast with late recurrence. However, the overall survival (OS) of patients with early recurrence and curative treatment did not significantly differ from that of non-recurring patients. For late recurrence, OS did not significantly differ from that of non-recurring patients, regardless of the proposed treatment. Aggressive and repeat treatments are therefore key to improve prognosis of patients with HCC.

Objective: Starting from the 1990’s minimally invasive methods such as endovenous laser ablation (EVLA), radiofrequency ablation (RFA), and ultrasound-guided foam sclerotherapy (UGFS) developed.Method: This study includes a total of 136 patients (81 women/55 men), of whom 22 (10 women/12 men) were treated with classic surgical stripping, 54 (32 women/22 men) with thermal ablation and 60 (39 women/21 men) with non-thermal ablation.Results: Twenty-two patients (10 women/12 men) were treated with surgical stripping. In one female patient a hematoma arose in the medial crural region postoperatively. A radiofrequency catheter (ThermoBLOCK TM) was used in the thermal ablation procedures in 54 patients (32 female/22 male). While permanent paresthesia occurred in one female patient after the procedure, temporary paresthesia occurred in 3 male patients postoperatively. Non-thermal ablation was performed in 60 patients (39 female/21 male). Even through a severe burning sensation was present in 6 patients (5 female/1 male) during the procedure, this symptom was only transient. In one of the patients, deep venous thrombosis (DVT) occurred at the level of the popliteal vein postoperatively at the sixth day.Conclusion: Even if thermal and non-thermal ablation and surgical procedures have the same pain decreasing rates, hematomas and a longer hospital stay are more frequent in surgical procedures., Amaç: 1990’lı yıllardan başlayarak endovenöz lazer ablasyon (EVLA), radyofrekans ablasyon (RFA) ve ultrason eşliğinde köpük skleroterapi (UGFS) gibi minimal invaziv yöntemler geliştirildi. Yöntem: Bu çalışma toplam 136 hastayı içermektedir (81 kadın/55 erkek) 22’ (10 kadın/12 erkek) klasik cerrahi stripping, 54’ (32 kadın/22 erkek) termal ablasyon ve 60’ (39 kadın/21 erkek) termal olmayan ablasyon ile tedavi edildi. Bulgular: Yirmi iki hasta (10 kadın/12 erkek) cerrahi stripping ile tedavi edildi. Bir kadın hastada operasyon sonrasında kruris medialinde hematom meydana geldi. 54 hastada (32 kadın/22 erkek) termal ablasyon işlemlerinde radyofrekans kateter (ThermoBLOCK TM) kullanıldı. Bir kadın hastada işlem sonrası kalıcı parestezi gelişti. 3 erkek hastada ameliyat sonrası geçici parestezi gelişti. 60 hastaya (39 kadın/21 erkek) termal olmayan ablasyon uygulandı. 6 hastada (5 kadın/1 erkek) işlem sırasında şiddetli yanma olmasına rağmen bu semptom geçiciydi. Bir hastada postoperatif altıncı günde popliteal ven düzeyinde derin ven trombozu (DVT) gelişti.Sonuç: Termal ve termal olmayan ablasyon ve cerrahi işlemler aynı ağrı azaltma oranlarına sahip olsa da cerrahi işlemlerde hematomlar ve hastanede daha uzun süre kalış daha sık görülür.

To evaluate the technical efficacy and Local Tumor Progression-free survival [LTPFS] of a high-precision liver ablation technique comprised by stereotactic-guidance, CT during hepatic arteriography-based imaging analysis, and computer-based software assessment of ablation margins, for the treatment of patients with colorectal liver metastasis referred to percutaneous liver ablation.

Microwave ablation is commonly used in soft tissue tumors, but its application in bone tumors has been barely analyzed. Antennas to treat bone tissue (~3 cm2), has been lately designed. Bone tumors at pathological stage T1 can reach 8 cm wide. An antenna cannot cover it; therefore, our goal is to evaluate the thermal performance of multi-antenna arrays. Linear, triangular, and square configurations of double slot (DS) and monopole (MTM) antennas were evaluated. A parametric study (finite element method), with variations in distance between antennas (ad) and bone thickness (bt) was implemented. Array feasibility was evaluated by SWR, ablated tissue volume, etc. The linear configuration with DS and MTM antennas showed SWR ≤ 1.6 for ad = 1 mm–15 mm and bt = 20 mm–40 mm, and ad = 10 mm–15 mm and bt = 25 mm–40 mm, respectively; the triangular showed SWR ≤ 1.5 for ad = 5 mm–15 mm and bt = 20 mm–40 mm and ad = 10 mm–15 mm and bt = 25 mm–40 mm. The square configuration (DS) generated SWR ≤ 1.5 for ad = 5 mm–20 mm and bt = 20 mm–40 mm, and the MTM, SWR ≤ 1.5 with ad = 10 mm and bt = 25 mm–40 mm. Ablated tissue was 4.65 cm3–10.46 cm3 after 5 min. According to treatment time and array configuration, maximum temperature and ablated tissue is modified. Bone tumors >3 cm3 can be treated by these antenna-arrays.

High-intensity focused ultrasound (HIFU) has been shown to be a valuable tool in the management of small liver tumors such as hepatocellular carcinoma (HCC). It has been shown to be a safe and effective means to ablate small HCC even in the presence of advanced cirrhosis. This review examines the challenges faced during HIFU ablation when the target tumors are located in difficult locations such as the liver dome, close to the rib cage, near large blood vessels or the heart, or adjacent to hollow viscera; and the special maneuvers employed to tackle such lesions.

The treatment outcomes of ultrasound-guided percutaneous thermal ablation of hepatocellular carcinoma in the caudate lobe with and without fusion imaging (FI) assistance were evaluated and compared. Twenty-six patients with 28 tumors in the FI group and 8 patients with 8 tumors in the non-FI group were included. Although a higher number of tumors measured >20 mm in the FI group, the technique efficacy and local tumor progression were similar between the 2 groups (P > .99 and P = .45, respectively). FI aided in the detection, guidance, and treatment monitoring of thermal ablation for caudate lobe hepatocellular carcinomas, especially for tumors measuring >20 mm.

This AUA Guideline focuses on evaluation/counseling/management of adult patients with clinically-localized renal masses suspicious for cancer, including solid-enhancing tumors and Bosniak 3/4 complex-cystic lesions.The Renal Mass and Localized Renal Cancer guideline underwent an update literature review which resulted in the 2021 amendment. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, additional information is provided as Clinical Principles and Expert Opinions (table 1[Table: see text]).Great progress has been made regarding the evaluation/management of clinically-localized renal masses. These guidelines provide updated, evidence-based recommendations regarding evaluation/counseling including the evolving role of renal-mass-biopsy (RMB). Given great variability of clinical/oncologic/functional characteristics, index patients are not utilized and the panel advocates individualized counseling/management. Options for intervention (partial-nephrectomy (PN), radical-nephrectomy (RN), and thermal-ablation (TA)) are reviewed including recent data about comparative-effectiveness/potential morbidities. Oncologic issues are prioritized while recognizing the importance of functional-outcomes for survivorship. Granular criteria for RN are provided to help reduce overutilization of RN while also avoiding imprudent PN. Priority for PN is recommended for clinical T1a lesions, along with selective utilization of TA, which has good efficacy for tumors≤3.0 cm. Recommendations for genetic-counseling have been revised and considerations for adjuvant-therapies are addressed. Active-surveillance and follow-up after intervention are discussed in an adjunctive article.Several factors require consideration during counseling/management of patients with clinically-localized renal masses including general health/comorbidities, oncologic-considerations, functional-consequences, and relative efficacy/potential morbidities of various management-strategies.

Objective Thermal ablation (TA) was implemented in public sector cervical cancer prevention services in Zambia in 2012. Initially introduced as a treatment modality in primary healthcare clinics, it was later included in mobile outreach campaigns and clinical research trials. We report the feasibility, acceptability, safety, and provider uptake of TA in diverse clinical contexts. Methods Screening services based on visual inspection with acetic acid were offered by trained nurses to non-pregnant women aged 25-59 years. Women with a type 1 transformation zone (TZ) were treated with same-visit TA. Those with a type 2 or 3 TZ, or suspicious for cancer, were managed with same-visit electrosurgical excision or punch biopsy, respectively. A provider survey was conducted. Results Between 2012 and 2020, 2123 women were treated with TA: primary healthcare clinics, n = 746; mobile outreach clinics, n = 1127; research clinics, n = 250. Of the 996 women treated in primary healthcare and research clinics, 359 (48%) were HIV positive. Mild cramping during treatment was the most common adverse effect. No treatment interruptions occurred. No major complications were reported in the early (6 weeks) follow-up period. Providers expressed an overwhelming preference for TA over cryotherapy. Conclusion TA was feasible, safe, and acceptable in diverse clinical contexts. It was the preferred ablation method of providers when compared with cryotherapy.

This report reviews the current data regarding the advantages of radiofrequency ablation for treating recurrent well-differentiated thyroid cancer. The literature favors early ablation of small recurrent lesions, providing the best results while offering decreased incidence of complications when compared to repeated surgical procedures. Nonetheless, recent studies have demonstrated promising results in larger advanced recurrent nodules extending to the neck or with tracheal invasion. Minimally invasive thermal ablation is carving out its role in the treatment of well-differentiated thyroid cancer. As new literature is available, centers train skilled physicians and long follow-up is obtained. Thermal ablation will become a valuable option in the management of recurrent tumors, due to its minimally invasive and localized characteristics.

Thermal ablation (TA) for benign thyroid nodules (BTNs) is widely accepted as an effective and safe alternative to surgery. However, studies on the long-term outcomes of TA have reported problems with nodule regrowth and symptom recurrence, which have raised the need for adequate control of regrowth. Therefore, a more complete TA with a longer-lasting treatment effect may be required. In this study, we review and discuss long-term outcomes and regrowth of BTNs following TA and evaluate factors affecting the long-term outcomes. We also discuss the management of regrowth based on long-term outcomes.

Background Microwave ablation (MWA) and radiofrequency ablation (RFA) have recently attracted interest as minimally invasive treatment modalities for papillary thyroid carcinoma (PTC). However, the ablation outcomes of T1N0M0 PTC are not well characterized. Purpose To evaluate the efficacy and safety of thermal ablation (MWA or RFA) of solitary T1N0M0 PTC in patients who were ineligible for (due to presence of comorbid cardiovascular disease, renal failure, other malignancy, etc) or who refused surgery. Materials and Methods This was a retrospective multicenter study of 847 patients (660 women) who underwent thermal ablation for PTC (673 T1a, 174 T1b) between March 2015 and March 2020; of these patients, 645 underwent MWA and 202 underwent RFA. The mean age of patients was 46 years ± 11 (standard deviation) (age range, 18-81 years); the mean follow-up time was 22 months ± 13 (range, 6-60 months). Changes in tumor size and volume and the rates of technical success, tumor disappearance, disease progression, and complications were assessed. Results The technical success rate was 100%. Relative to preablation measurements, the maximum diameter and volume of the ablation zone increased during the 1st month after ablation (P < .001), whereas there was no difference by the 3rd month; subsequently, the tumors showed reduction in size at 6, 9, and 12 months (all P < .001). Complete disappearance of tumors occurred in 68% of patients (577 of 847; 69% [466 of 673] in the T1a group vs 64% [111 of 174] in the T1b group; P < .001). The postablation disease progression rate was 1.1% (nine of 847 patients; 0.9% [six of 673 patients] in the T1a group vs 1.7% [three of 174 patients] in the T1b group; P = .54). The overall complication rate was 3.4% (29 of 847 patients; 2.7% [18 of 673 patients] in the T1a group vs 6.3% [11 of 174 patients] in the T1b group; P = .02). Conclusion This multicenter study provided evidence that thermal ablation is an effective and safe treatment option in selected -patients with solitary T1N0M0 papillary thyroid carcinoma. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Baek and Cho in this issue.

Patients with varicose veins of the lower extremities with osteoarthritis of the knee often experience improvement in knee joint symptoms after endovascular treatment. We considered that it was important to decide the operation indication of lower extremity varices, to know the correlation between the two diseases in the treatment of varicose veins. To investigate the postoperative improvement of knee symptoms related to varicose veins with knee osteoarthritis, we conducted a questionnaire survey for a total of 12 months, from December 2014 to May 2015 and from October 2018 to March 2019. The participants were 35 patients (7 men and 28 women) with varicose veins complicated with knee osteoarthritis. We classified knee osteoarthritis according to a grading scale and compared the improvement of knee symptoms after endovenous thermal ablation. The higher the knee grade, the lower the degree of improvement. However, the improvement was observed in all knee osteoarthritis grades, and as a whole, 25 patients (71.4%) have experienced improvement of subjective symptoms. For patients with knee osteoarthritis, we strongly recommend surgical treatment of the varicose veins regardless of the progression of knee grade. (This is a translation of Jpn J Phlebol 2019; 30(3): 279-283.).

Temperature monitoring inside tissue undergoing minimally invasive thermal ablation is a primary goal to improve the clinical outcomes. Existing techniques for temperature measurements, classified as invasive or contactless, have limited clinical practice applications due to several practical issues. Fiber Bragg grating sensors (FBG) can be a valid solution since they can perform accurate and multi-point temperature measurements by inserting a single and small fiber optic within the tissue. Notwithstanding, their cross-sensitivity to strain may cause measurement errors during thermal procedures. Indeed, several organs (e.g., lungs, liver, pancreas) can strain gratings due to movements caused by breathing. To date, only a few studies have specifically addressed this concern, despite the wide use of FBGs in this field. To overcome this lack, we estimated the artefact of the FBGs output in response to lungs’ movements induced by breathing. This investigation was carried out by inserting FBGs within a manually ventilated lung model ( ex vivo swine lungs). We measured both the lungs’ movements during breathing by a Motion Capture system and the related fluctuations of the FBGs’ output. Moreover, we performed the same experiments during thermal ablation of lungs to assess the mentioned artefact’s influence. In this study, we demonstrated the relevance of the respiratory artefact on FBGs, and also the possibility to correct this error during thermal ablation.

HCC incidence continues to increase worldwide and is most frequently discovered at an advanced stage when limited curative options are available. Combination locoregional therapies have emerged to improve patient survival and quality of life or downstage patients to curative options. The increasing options for locoregional therapy combinations require an understanding of the expected post-treatment imaging appearance in order to assess treatment response. This review aims to describe the synergy between TACE combined with thermal ablation and TACE combined with SBRT. We will also illustrate expected imaging findings that determine treatment efficacy based on the mechanism of tissue injury using the LI-RADS Treatment Response Algorithm.

Prospective evaluation of prediction models for local tumor progression, intrahepatic progression outside the ablation zone and treatment recommender for outcomes after percutaneous thermal ablation of colorectal liver metastasis.

IntroductionHepatocellular carcinoma (HCC) accounts for nearly 90% of primary liver cancers, with estimates of over 1 million people affected by 2025. We aimed to explore the impacting role of an iterative surgical treatment approach in a cohort of HCC patients within the Milan criteria, associated with clinical risk factors for tumor recurrence (RHCC) after liver transplant (LT) and loco-regional therapies (LRT), as well as liver resection (LR) and/or microwave thermal ablation (MWTA).MethodsWe retrospectively analyzed our experience performed during an 8-year period between January 2013 and December 2021 in patients treated for HCC, focusing on describing the impact on preoperative end-stage liver disease severity, oncologic staging, tumor characteristics, and surgical treatments. The Cox model was used to evaluate variables that could predict relapse risks. Relapse risk curves were calculated according to the Kaplan–Meier method, and the log-rank test was used to compare them.ResultsThere were 557 HCC patients treated with a first-line approach of LR and/or LRTs (n = 335) or LT (n = 222). The median age at initial transplantation was 59 versus 68 for those whose first surgical approach was LR and/or LRT. In univariate analysis with the Cox model, nodule size was the single predictor of recurrence of HCC in the posttreatment setting (HR: 1.61, 95% CI: 1.05–2.47, p = 0.030). For the LRT group, we have enlightened the following clinical characteristics as significantly associated with RHCC: hepatitis B virus infection (which has a protective role with HR: 0.34, 95% CI: 0.13–0.94, p = 0.038), number of HCC nodules (HR: 1.54, 95% CI: 1.22–1.94, p < 0.001), size of the largest nodule (HR: 1.06, 95% CI: 1.01–1.12, p = 0.023), serum bilirubin (HR: 1.57, 95% CI: 1.03–2.40, p = 0.038), and international normalized ratio (HR: 16.40, 95% CI: 2.30–118.0, p = 0.006). Among the overall 111 patients with RHCC in the LRT group, 33 were iteratively treated with further curative treatment (12 were treated with LR, two with MWTA, three with a combined LR-MWTA treatment, and 16 underwent LT). Only one of 18 recurrent patients previously treated with LT underwent LR. For these RHCC patients, multivariable analysis showed the protective roles of LT for primary RHCC after IDLS (HR: 0.06, 95% CI: 0.01–0.36, p = 0.002), of the time relapsed between the first and second IDLS treatments (HR: 0.97, 95% CI: 0.94–0.99, p = 0.044), and the impact of previous minimally invasive treatment (HR: 0.28, 95% CI: 0.08–1.00, p = 0.051).ConclusionThe coexistence of RHCC with underlying cirrhosis increases the complexity of assessing the net health benefit of ILDS before LT. Minimally invasive surgical therapies and time to HCC relapse should be considered an outcome in randomized clinical trials because they have a relevant impact on tumor-free survival.

Purpose: To investigate the safety, feasibility, and outcomes of High-Intensity Focused Ultrasound (HIFU) for the treatment of solid tumors in a spontaneous canine cancer model. Methods: Dogs diagnosed with subcutaneous solid tumors were recruited, staged and pretreatment biopsies were obtained. A single HIFU treatment was delivered to result in partial tumor ablation using a commercially available HIFU unit. Tumors were resected 3-6 days post HIFU and samples obtained for histopathology and immunohistochemistry. Total RNA was isolated from paired pre and post treated FFPE tumor samples, and quantitative gene expression analysis was performed using the nCounter Canine IO Panel. Results: A total of 20 dogs diagnosed with solid tumors were recruited and treated in the study. Tumors treated included Soft Tissue Sarcoma (n = 15), Mast Cell Tumor (n = 3), Osteosarcoma (n = 1), and Thyroid Carcinoma (n = 1). HIFU was well tolerated with only 1 dog experiencing a clinically significant adverse event. Pathology confirmed the presence of complete tissue ablation at the HIFU targeted site and immunohistochemistry indicated immune cell infiltration at the treated/untreated tumor border. Quantitative gene expression analysis indicated that 28 genes associated with T-cell activation were differentially expressed post-HIFU. Conclusions: HIFU appears to be safe and feasible for the treatment of subcutaneous canine solid tumors, resulting in ablation of the targeted tissue. HIFU induced immunostimulatory changes, highlighting the canine cancer patient as an attractive model for studying the effects of focal ablation therapies on the tumor microenvironment. Published version

Addendum to "Prospective observational evaluation of predictive models for thermal ablation outcomes of colorectal liver metastasis". This is a prospective evaluation of two prediction models for eligibility for salvage loco-regional therapy after intrahepatic progression following percutaneous thermal ablation of colorectal liver metastases. The study is for the same patient cohort as the original protocol.

Objectives The aim of this study was to systemically review and analyze the efficacy of cyanoacrylate ablation (CA) in comparison with endovenous thermal ablation (ETA) for the treatment of incompetent saphenous veins. Methods A systematic literature search was conducted using databases of Pubmed, Embase, and Cochrane Library from the times of their inception to April 2020. Studies were selected based on inclusion and exclusion criteria after assessing the risk of bias in comparative studies with Cochrane and rating quality of evidence with the GRADE methodology. The meta-analysis was carried out using the Review Manager 5.4 program to conduct homogeneity tests. Results One cohort study and three randomized controlled trials (RCT), including a total of 1457 participants were included in the meta-analysis. ETA included endovenous laser ablation (ELVA) and radiofrequency ablation (RFA) in the selected studies. Comparison between CA and a combination of EVLA and RFA or RFA alone were carried out in two of RCTs, while comparison between CA with EVLA was conducted in one RCT and the cohort study. There was no statistical difference in closure rates between CA and ETA after pooled analysis. Similar symptom alleviation observed between different groups. However, the CA group showed a lower ecchymosis rate than RFA and a significantly lower incidence of adverse events, such as ecchymosis, phlebitis and paresthesia, than EVLA. Compared with ETA, the patients received CA treatment exhibited lower pain scores in a shorter procedure duration without needing compression stocking, returned to normal life sooner, and had significantly better quality of care. There was no significant difference in the number needed to treat for additional therapy after three months of follow-up between groups. Conclusions This meta-analysis indicates that CA has better overall outcomes than ETA and offers superior clinical benefits in the treatment of incompetent saphenous veins.

To outline future applications of thermal ablation technologies for head and neck pathologies. Thermal ablation technologies are most widely used for benign thyroid disease. However, other potential uses include parathyroid disease, salivary tumors, and papillary thyroid microcarcinomas. The anatomical proximity of critical structures to the thyroid bed raises important issues regarding patient safety and morbidity with thermal ablation techniques for these novel indications and potential maneuvers to minimize risk are also discussed. While benign thyroid lesions offer an excellent demonstration of proof of concept for ablative technologies, it is likely that surgeons skilled in thermal ablation techniques will employ this skillset to the benefit of future patients with pathologies ranging from the parotid to the parathyroid and beyond.

Objectives The aim of our study was to evaluate the role of flavonoids in the improvement of post-operative symptoms after endovenous thermal ablation (EVTA). Methods A prospective comparative study of 120 consecutive patients undergoing EVTA of the greater saphenous vein associated with phlebectomies was undertaken. Patients were grouped in those receiving micronized purified flavonoid fraction (MPFF- 60 patients) agent 500 mg Bid 7 days pre- and 30 days post- operatively (MPFF group) and those in the control group (60 patients) who did not. Demographics, intra-operative details, Clinical –Etiology- Anatomy- Pathophysiology (CEAP) clinical class, 10-cm Visual Analog Scale (VAS) for pain, Venous Clinical Severity Score (VCSS) and Chronic Venous Insufficiency Quality-of-Life Questionnaire (CΙVIQ-20) were recorded. Primary outcome was the postoperative pain assessement using the VAS scale and CIVIQ pain score. Secondary outcomes included assessement of VCSS and CΙVIQ-20 scores. Results There were no significant differences between the groups regarding demographics, clinical and procedural characteristics. Patients in MPFF group reported significantly lower VAS pain levels than control group at 7- (−3.6 ± 1.2 vs −2.7 ± 1.9, p Conclusions Administration of flavonoids in patients undergoing EVTA associated with phlebectomies reduces pain by a small amount during early postoperative period.

Confidence in long-term treatment results of thermal ablation for papillary thyroid microcarcinoma (PTMC) is required in comparison with active surveillance. The objective of this meta-analysis is to report 5-year follow-up results of thermal ablation for PTMC. Ovid MEDLINE and EMBASE databases were searched through May 30, 2020, for studies reporting outcomes in patients with PTMC treated with thermal ablation and followed up for at least 5 years. Data were extracted and methodological quality was assessed independently by two radiologists according to the PRISMA guidelines. Three studies, involving 207 patients with 219 PTMCs, met the inclusion criteria through database searches. None of these patients experienced local tumor recurrence, lymph node metastasis, or distant metastasis or underwent delayed surgery during a mean pooled 67.8-month follow-up. Five new tumors appeared in the remaining thyroid gland of four patients, with four of these tumors successfully treated by repeat thermal ablation. The pooled mean major complication rate was 1.2%, with no patient experiencing life-threatening or delayed complications. Thermal ablation is an excellent local tumor control method in patients with low-risk PTMC, with low major complication rates at 5 years. • No local tumor recurrence, lymph node metastasis, or distant metastasis was noted by thermal ablation during follow-up of 5 years and none underwent delayed surgery. • The pooled mean major complication rate was 1.2%.

Management of high-risk surgical patients with cholecystitis poses a significant clinical problem. These patients are often left with the options of permanent cholecystostomy tube drainage or high-risk surgery. Numerous attempts have been made over the past 4 decades to fulfill the need for a minimally invasive, definitive treatment option for such gallbladder disease. These attempts have largely focused on endoluminal ablation with a variety of sclerosants and have been unable to reliably achieve permanent gallbladder devitalization. The advent of modern percutaneous devices and techniques have provided further opportunity to develop minimally invasive treatment options for high-risk patients. Cryoablation, a thermal ablation modality that induces cell death through tissue freezing, has recently emerged as a promising potential option to treat gallbladder disease. Early studies have demonstrated good technical and clinical success, and a prospective trial is ongoing. This manuscript explains the clinical need for gallbladder cryoablation, briefly revisits historical minimally invasive treatments, describes cryoablation technology and why it is well suited for the gallbladder, and reviews the preclinical and clinical studies evaluating the safety and efficacy of gallbladder cryoablation.

Objective To measure patient preferences for attributes associated with thermal ablation and non-thermal, non-tumescent varicose vein treatments. Methods Data were collected from an electronic patient-preference survey taken by 70 adult participants (aged 20 years or older) at 3 Center for Vein Restoration clinics in New Jersey from July 19, 2019, through August 13, 2019. Survey participation was voluntary and anonymous (participation rate of 80.5% [70/87]). Patients were shown 10 consecutive screens that displayed 3 hypothetical treatment scenarios with different combinations of 6 attributes of interest and a “None” option. Choice-based conjoint analysis estimated the relative importance of different aspects of care, trade-offs between these aspects, and total satisfaction that respondents derived from different healthcare procedures. Market simulation analysis compared clusters of attributes mimicking thermal ablation and non-thermal, non-tumescent treatments. Results Of the 6 attributes studied, out-of-pocket expenditures were the most important to patients (37.2%), followed by postoperative discomfort (17.1%), risk of adverse events (16.3%), time to return to normal activity (11.0%), number of injections (10.0%), and number of visits (8.4%). Patients were willing to pay the most to avoid postoperative discomfort ($68.9) and risk of adverse events ($65.8). The market simulation analysis found that, regardless of the level of out-of-pocket spending, 60%-80% of respondents favored attribute combinations corresponding to non-thermal, non-tumescent procedures over thermal ablation, and that less than 1% of participants would forgo either treatment under no cost-sharing. Conclusions Patients are highly sensitive to out-of-pocket costs for minimally-invasive varicose vein treatments. Market simulation analysis favored non-thermal, non-tumescent procedures over thermal ablation.

Hepatocellular carcinoma (HCC) is a common malignancy worldwide, recognized as the fourth most common cause of cancer related death. Many risk factors, leading to liver cirrhosis and associated HCC, have been recognized, among them viral hepatitis infections play an important role worldwide. Patients suffering from chronic kidney disease (CKD), especially those on maintenance dialysis, show a higher prevalence of viral hepatitis than the general population what increases the risk of HCC onset. In addition, renal dysfunction may have a negative prognostic impact on both immediate and long-term outcomes after malignancy treatment. Several interventional procedures for the treatment of HCC are currently available: thermal ablation, transcatheter arterial chemoembolization, liver surgery or even liver transplantation. The Barcelona Clinic Liver Cancer system provides an evidence-based treatment algorithm to address different categories of patients to the most-effective treatment in consideration of the extension of disease, liver function and performance status. Liver resection and transplantation are usually reserved to patients with early stage HCC and acceptable performance status, while the other treatments are more indicated in case of impaired liver function or locally advanced or unresectable tumors. However, there is no validated treatment algorithm for HCC in CKD patients, mainly due to the rarity of reports in this cohort of patients. Hereby we discuss the available evidences on interventional HCC treatments in CKD patients, and briefly report up-to-date pharmacological therapy for HCC patients affected by viral hepatitis.

Background: Laparoscopic microwave ablation (MWA) of hepatocellular carcinoma is underutilized and predictors of survival in this setting are not well characterized. Methods: The prognostic value of clinicopathologic variables was evaluated on progression-free survival (PFS) and overall survival (OS) by univariate and multivariate analyses. The aim of this study was to evaluate a preferred laparoscopic MWA approach in HCC patients that are not candidates for percutaneous ablation and further classify clinicopathologic factors that may predict survival outcomes following operative MWA in the setting of primary HCC. Results: 184 patients with HCC (median age 66, (33–86), 70% male) underwent laparoscopic MWA (N = 162, 88% laparoscopic) compared to 12% undergoing open MWA (N = 22). Median PFS was 29.3 months (0.2–170) and OS was 44.2 months (2.8–170). Ablation success was confirmed in 100% of patients. Ablation recurrence occurred in 3% (6/184), and local/hepatic recurrence occurred in 34%, at a median time of 19 months (9–18). Distant progression was noted in 8%. Median follow up was 34.1 months (6.4–170). Procedure-related complications were recorded in six (9%) patients with one 90-day mortality. Further, >1 lesion, AFP levels ≥ 80 ng/mL, and an “invader” on pre-operative radiology were associated with increased risk of progression (>1 lesion HR 2.92, 95% CI 1.06 –7.99, p = 0.04, AFP ≥ 80 ng/mL HR 4.16, 95% CI 1.71–10.15, p = 0.002, Invader HR 3.16, 95% CI 1.91–9.15, p = 0.002 ) and mortality (>1 lesion HR 3.62, 95% CI 1.21–10.81, p = 0.02], AFP ≥ 80 ng/mL HR 2.87, 95% CI 1.12–7.35, p = 0.01, Invader HR 3.32, 95% CI 1.21–9.81, p = 0.02). Conclusions: Preoperative lesion number, AFP ≥ 80 ng/mL, and an aggressive imaging characteristic (Invader) independently predict PFS and OS following laparoscopic operative MWA.

Vertebral body metastases (VBM) are one of the most frequent sites of bone metastasis, and their adequate therapeutic management still represents an insidious challenge for both oncologists and surgeons. A possible alternative treatment for VBM is radiofrequency ablation (RFA), a percutaneous technique in which an alternating current is delivered to the tumor lesion producing local heating and consequent necrosis. However, RFA alone could alter the biomechanics and microanatomy of the vertebral body, thus increasing the risk of post-procedure vertebral fractures and spine instability, and indeed the aim of the present study is to investigate the effects of RFA on spine stability. A systematic review according to PRISMA-P guidelines was performed, and 17 papers were selected for the systematic review. The results show how RFA is an effective, safe, and feasible alternative to conventional radiotherapy for the treatment of VBM without indication for surgery, but spine stability is a major issue in this context. Although exerting undeniable benefits on pain control and local tumor recurrence, RFA alone increases the risk of spine instability and consequent vertebral body fractures and collapses. Concomitant safe and feasible therapeutic strategies such as percutaneous vertebroplasty and kyphoplasty have shown synergic positive effects on back pain and improvement in spine stability.

Background: Previous studies have confirmed the superiority of using erbium lasers (2940, 2780 nm) over other lasers in the debonding of ceramic brackets due to their safety and effectiveness. The most important factor in the debonding of aesthetic brackets is the transmission of the erbium laser through the aesthetic bracket to the adhesive resin. Objective: To identify the transmission of the 2940 nm wavelength through different types of aesthetic brackets. Materials and methods: A total of 60 aesthetic brackets were divided into six equal groups (10 monocrystalline sapphire brackets—Radiance, AO; 10 monocrystalline sapphire brackets—Absolute, Star Dentech; 10 polycrystalline brackets—20/40, AO; 10 polycrystalline brackets—3M Unitek Gemini Clear Ceramic; 10 silicon brackets—Silkon Plus, AO; 10 composite brackets—Orthoflex, OrthoTech). The aesthetic brackets were mounted in a Fourier transform infrared spectrophotometer (FTIR IRPrestige-21, SHIMADZU) following the typical spectroscopy lab procedure for such samples. The transmission ratio for the 2940 nm wavelength was obtained using IRsolution software. The mean transmission values of the tested groups were compared using a one-way analysis of variance (ANOVA) test followed by a Bonferroni test (post-hoc test). Results: The highest transmission ratio was observed for the Radiance sapphire brackets (64.75%) and the lowest was observed for the 3M polycrystalline brackets (40.48%). The differences among the Aesthetic brackets were significant (p < 0.05). Conclusions: The thick polycrystalline and composite brackets have the lowest transmissibility, whereas the monocrystalline sapphire brackets have the highest transmissibility for the 2940 nm wavelength, meaning that there is a higher possibility of debonding them with a hard tissue laser through thermal ablation.

INTRODUCTION Endoscopic mucosal resection (EMR) is an effective therapy for naive large nonpedunculated colorectal polyps (N-LNPCPs). The best approach for the treatment of previously attempted LNPCPs (PA-LNPCPs) is undetermined. METHODS EMR performance for PA-LNPCPs was evaluated in a prospective observational cohort of LNPCPs ≥20 mm. Efficacy was measured by technical success (removal of all visible polypoid tissue during index EMR) and recurrence at first surveillance colonoscopy (SC1). Safety was assessed by clinically significant intraprocedural bleeding, deep mural injury types III-V, clinically significant post-EMR bleeding, and delayed perforation. RESULTS From January 2012 to October 2019, 158 PA-LNPCPs and 1,134 N-LNPCPs underwent EMR. Median PA-LNPCP size was 30 mm (interquartile range 25-46 mm). Technical success was 93.0% and increased to 95.6% after adjusting for 2-stage EMR. Cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST) was required for nonlifting polypoid tissue in 73 (46.2%). Median time to SC1 was 6 months (interquartile range 5-7 months). Recurrence occurred in 9 (7.8%). No recurrence was identified among 65 PA-LNPCPs which underwent margin thermal ablation at SC1 vs 9 (18.0%; P < 0.001) which did not. There were significant differences in resection duration (35 vs 25 minutes; P < 0.001), technical success (93.0% vs 96.6%; P = 0.026), and use of CAST (46.2% vs 7.6%; P < 0.001), between PA-LNPCPs and N-LNPCPs. When adjusting for 2-stage EMR, no difference in technical success was identified (95.6% vs 97.8%; P = 0.100). No differences in adverse events or recurrence were identified. DISCUSSION EMR, using auxillary techniques where necessary, can achieve high technical success and low recurrence frequencies for PA-LNPCPs.

BACKGROUND: To investigate the feasibility and accuracy of using preoperative and postoperative three-dimensional contrast-enhanced ultrasound (3D CEUS) fusion imaging in the evaluation of safety margins after thermal ablation of hepatocellular carcinoma (HCC). METHODS: A total of the 24 patients with HCC who underwent microwave ablation (MWA) between June 2020 and December 2020 were enrolled in this study. All patients received preoperative and postoperative 3D CEUS. The preoperative and postoperative 3D CEUS images were then fused. The success rate and evaluation time were recorded. The ablation margin and whether or not the safety margin was reached were calculated and recorded. If the ablation safety margin was not reached, the residual ablation volume needed to cover the safety margin was calculated automatically. The agreement between contrast-enhanced computed tomography(CECT) and 3D CEUS fusion imaging in the evaluation of ablation margins was explored using the kappa coefficient. RESULTS: The 3D CEUS fusion success rate was 95.8% (23/24), with a mean fusion time of (4.1±1.8) minutes. Twenty-three tumors were completely ablated, and the safety margin was achieved for 9 tumors. The ablation margin of 14 tumors was 5 mm. The 2 methods showed excellent consistency, with a Kappa value of 0.911 (P=0.000012). CONCLUSIONS: This study has presented a novel mono-modality fusion imaging method based on CEUS. We demonstrated that 3D CEUS fusion has a short fusion time and a high success rate, as well as good consistency with enhanced CT fusion. Therefore, 3D CEUS fusion is a feasible and accurate tool for evaluating the immediate efficacy of thermal ablation of HCC.

Objective: Hepatocellular carcinoma (HCC) is one of the most dangerous, and fatal cancers. Thermal ablation proved its power as the best treatment method for HCC. In microwave thermal ablation, microwave probes are used to generate electromagnetic waves (EMW) at microwave (MW) frequency 2.45 GHz. In this paper, the design/model of a novel microwave ablation probe, namely a single slot with a shifted 1T-ring probe is presented for HCC therapy. Methods: A Finite Element Method (FEM) is employed to model the probe and the hepatic tumor liver tissues. The relation between the tip of probe position and the center of the hepatic tumor was studied to determine the best probe location at which a minimum MW power is required to ablate the entire tumor tissues with the smallest damage in the nearby healthy tissues to the tumor. Results: The results indicated that the ablated part of the tissues varies depending on the MW probe type, the amount of used power, the location of the probe, and the exposure time. Hepatic tumors’ diameters from 2-5cm were studied. Conclusion: It was shown that the proposed SSS 1T-ring (single slot with shifted 1T-ring) probe provided the best ablation performance when the probe's tip placed below the tumor's center by 11 mm, which achieved 100% damage in the tumor tissues using 6 W power for 10 minutes. Significance: When the probe's tip is located at the center of the tumor, the ablation rate was 73.45% in the tumor tissues under the same conditions.

In children and adolescents affected by musculoskeletal sarcomas (both soft tissue and bone sarcomas), the presence of lung metastases is a frequent complication, that should be known since the patient’s prognosis, as management, and treatment depend on it. During the staging phase, the detection of lung metastases should be sensitive and specific, and it should be carried out by minimizing the radiation exposure. To deal with this problem, imaging has reached important goals in recent years, thanks to the development of cone-beam CT or low-dose computed tomography, with some new iterative reconstruction methods, such as Veo and ASIR. Imaging is also fundamental for the possibility to perform lung biopsies under CT guidance, with less morbidity, less time-consumption, and shorter recovery time, compared to surgical biopsies.Moreover, important results have also been demonstrated in the treatment of lung metastases, due to the improvement of new mini-invasive image-guided percutaneous thermal ablation procedures, which proved to be safe and effective also in young patients.

Purpose Predicting early local tumor progression after thermal ablation treatment for colorectal liver metastases patients is critical for the decision of subsequent follow-up and treatment. Radiomics features derived from medical images show great potential for prediction and prognosis. The aim is to develop and validate a machine learning radiomics model to predict local tumor progression based on the pre-ablation CT scan of colorectal liver metastases patients. Materials and Methods Ninety patients with colorectal liver metastases (140 lesions) treated by ablation were included in the study and were randomly divided into a training (n = 63 patients/n = 94 lesions) and validation (n = 27 patients/n = 46 lesions) cohort. After manual lesion volume segmentation and preprocessing, 1593 radiomics features were extracted for each lesion. Three machine learning survival models were constructed based on (1) radiomics features, (2) clinical features and (3) a combination of clinical and radiomics features to predict local tumor progression free survival. Feature reduction and machine learning modeling were performed and optimized with sequential model-based optimization. Results Median follow-up was 24 months (range 6-115). Thirty-one (22%) lesions developed local tumor progression. The concordance index in the validation set to predict local tumor progression free survival was 0.78 (95% confidence interval [CI]: 0.77-0.79) for the radiomics model, 0.56 (95%CI: 0.55-0.57) for the clinical model and 0.79 (95%CI: 0.78-0.80) for the combined model. Conclusion A machine learning-based radiomics analysis of routine clinical CT imaging pre-ablation could act as a valuable biomarker model to predict local tumor progression with curative intent for colorectal liver metastases patients.

To develop a radiomics model based on dynamic contrast-enhanced ultrasound (CEUS) to predict early and late recurrence in patients with a single HCC lesion ≤ 5 cm in diameter after thermal ablation. We enrolled patients who underwent thermal ablation for HCC in our hospital from April 2004 to April 2017. Radiomics based on two branch convolution recurrent network was utilized to analyze preoperative dynamic CEUS image of HCC lesions to establish CEUS model, in comparison to the conventional ultrasound (US), clinical, and combined models. Clinical follow-up of HCC recurrence after ablation were taken as reference standard to evaluate the predicted performance of CEUS model and other models. We finally analyzed 318 patients (training cohort: test cohort = 255:63). The combined model showed better performance for early recurrence than CUES (in training cohort, AUC, 0.89 vs. 0.84, P

Background This study aims to investigate the current use of pediatric flexible bronchoscopy (PFB) in western China. Methods A cross-sectional survey was conducted in western China between January 1, 2018 to December 30, 2018. Fifty-four centers were invited to answer a questionnaire for seeking information about performance of PFB. The data collected were analyzed to investigate the current status of western China, and hierarchical cluster analysis was conducted to identify developmental level of PFB of cities. Results Forty-seven centers were included in analysis. A total of 22,585 flexible bronchoscopies were carried out in the participating centers from January 1, 2018 to December 30, 2018. Eight centers (17.0%) performed more than 1,000 pediatric flexible bronchoscopies for children, but 20 centers (42.6%) performed less than 100. The median proportion of systematic and professional trained physicians in a single team was 50%, and the pooled rate was 59% (95% CI, 47-70%). Only 10, 8 and 11 centers performed balloon dilatation, thermal ablation and cryoablation, respectively. Obvious cough was the most frequent complication after the PFB procedure, the pooled rate is 24% (95% CI, 18-29%). No one died during and after the PFB procedure. Hierarchical cluster analysis showed that the development of PBF in western China varies, and Chongqing might be the most developed area in PFB use in western China. Conclusions Flexible bronchoscopy in children is now a mature and safe procedure, while the development of PFB varies in western China, especially for the advanced bronchoscopic intervention.