超声在冷循环射频治疗肝癌中的临床价值

目的：探讨超声在冷循环射频治疗肝癌中的临床价值。方法：应用冷循环射频电极对55例中小肝癌共67个病灶进行毁损治疗。经皮超声引导穿刺治疗45例,术中超声加直视治疗10例。术中超声进行实时监测,术后利用超声,CT进行监测追踪。结果：病灶完全坏死率为59．7％(40／67),血流信号完全消失82．1％(46／56),部分消失17．9％(10／56)。结论：射频毁损治疗是对目前以手术为主多种方法并举的综合治疗肝癌的一个重要补充,超声不但能准确引导定位,而且对于疗程进展和术后监测都很有帮助。     

肝脏恶性肿瘤射频消融术后早期FS-T2WI消融区周围水肿环评价消融疗效的应用

目的探讨肝脏恶性肿瘤射频消融(RFA)术后早期FS-T2WI消融区周围水肿环形态用于评价RFA疗效的价值。方法收集接受RFA治疗的18例肝癌及4例肝转移瘤患者,于术后第3天行MR平扫,观察FS-T2WI中消融区周围水肿环的形态特点;随访复查MR平扫、多期增强扫描及肿瘤标志物,评价根据FS-T2WI水肿环连续性判断RFA疗效的价值。结果消融后,22例病灶FS-T2WI消融区周围均出现高信号水肿环。19例水肿环连续,其中11例厚薄均匀,8例厚薄不均匀但形态规整、边界清晰;术后随访均无异常强化,肿瘤标志物稳定,提示消融完全。3例水肿环不连续,局部可见外凸稍高信号结节,术后1个月增强MRI可见结节状动脉期强化,血清甲胎蛋白升高,提示消融区域未完全覆盖肿瘤区域,消融不完全。结论肝脏恶性肿瘤RFA后早期FS-T2WI消融区周围水肿环对评价疗效具有一定价值,尤其对于判断短期疗效意义重大。     

Treatment of invasive breast carcinoma with ultrasound-guided radiofrequency ablation

BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive thermal ablation technique. This study reports the safety and efficacy of RFA as a minimally invasive strategy for breast cancers <3 cm diameter in postmenopausal women. METHODS: Twenty-two postmenopausal women (aged 60 years or older) with clinical T-1N0 core biopsy proven breast cancers were studied. Thermocoagulation was undertaken using a sonographically guided RF probe under local anesthesia and sedation. The ablated tumor was resected between 1 and 2 weeks later. Endpoints were technical success, completeness of tumor kill, marginal clearance, skin damage, and patient reports of pain and procedural acceptability. RESULTS: The procedure was well tolerated and cosmesis was excellent. Pathology revealed a central ablation zone surrounded by hyperemia. Coagulative necrosis was complete in 19 of 22 patients. Disease at the ablation zone margin was found in 3 patients and 5 patients had disease distant to the ablation zone consisting of multifocal tumors (2), in-transit metastasis (1), and extensive ductal carcinoma in situ with microinvasive carcinoma (2). Ninety-five percent of patients would be willing to have RFA again. CONCLUSIONS: Radiofrequency ablation can be safely applied in an outpatient setting with acceptable patient tolerance. By itself, RFA cannot be considered effective local therapy. Trials to evaluate RFA complemented with breast irradiation are justified.     

Radiofrequency interstitial tumor ablation: dry electrode

With the shift in the treatment of small renal tumors from radical extirpative surgery to nephron-sparing approaches, dry-electrode radiofrequency ablation (RFA) has emerged as one potential modality. This application of RF energy leads to the production of heat within the treatment zone secondary to the native impedance of living tissue. Animal studies and human clinical series have demonstrated that RFA can create controlled, targeted, reproducible, and lethal lesions. Most clinical series have reported promising results, although some authors question the totality of tumor destruction by RFA. With time, the efficacy of RFA, as measured by patient survival, will be determined. Once this is known, RFA may be compared with other therapeutic modalities for small renal tumors to determine its place.     

First prize: direct real-time temperature monitoring for laparoscopic and CT-guided radiofrequency ablation of renal tumors between 3 and 5 cm

PURPOSE: To evaluate our experience with radiofrequency ablation (RFA) of renal tumors in the range of 3 to 5 cm. PATIENTS AND METHODS: A series of 96 patients underwent 104 tumor laparoscopic or percutaneous CT-guided RFAs. We identified 37 tumors between 3 and 5 cm at the time of the ablation. Non-conducting temperature probes, independent of the radiofrequency (RF) electrode, were placed at the peripheral and deep margins of the tumor in order to achieve real-time temperature monitoring of the ablation zone. All ablations were continued until the peripheral and deep temperature probes reached 60 degrees C. RESULTS: All 37 patients (100%) achieved complete necrosis at the initial session. There were two radiographic failures at 9 months and 30 months that required a second treatment (95% radiographic success rate). Tissue samples taken at the time of the re-treatment (one partial nephrectomy with numerous biopsies of the deep and peripheral margins and one repeat ablation with eight core biopsies) showed no evidence of viable tumor with hematoxylin and eosin or nicotinamide adenine dinucleotide viability stains. The average length of follow-up was 11.3 months (range 1-44 months). No patient with localized disease at the time of the RFA developed local extension or metastatic disease in follow-up. CONCLUSIONS: The majority of renal tumors between 3 and 5 cm can be ablated with complete necrosis in a single session. Placement of independent temperature probes at the peripheral and deep margins of the tumor provides real-time monitoring that assists in the deployments of the RF electrode and determining the appropriate duration of the ablation cycles. Attention to real-time thermometry decreases the need for repeat sessions to achieve complete necrosis for larger tumors. Likewise, real-time thermometry decreases the incidence of overtreatment of normal parenchyma and prevents collateral damage to adjacent vital structures (ureter, pancreas, bowel, spleen, nerves) outside the desired zone of ablation.     

Radiofrequency ablation for metastatic lung tumor

BACKGROUND: Radiofrequency ablation (RFA) is a thermal ablation technique which results in coagulative necrosis. Several preliminary studies have evaluated the efficacy of RFA for liver tumor and benign prostate disease, but few studies for lung tumor. We experienced RFA for a metastatic lung tumor and it was effective. CASE: A 61-year-old woman was admitted to our hospital with chest pain. Extended thymothymomectomy with lymph node dissection was performed after diagnosis of thymic carcinoid. After 14 months, multiple small lung nodules, which had been 5-10 mm in diameter, were appeared and resected. However, 23 months after the first operation and 14 months after the second operation, multiple small lung nodules were appeared again and RFA was performed for 1 tumor without any complications. We used RITA 500 PA (RITA Medical Systems, INC.) and quadruple-hook radiofrequency probe with electrodes. Under local anaesthesia and ultrasound guidance, the probe was inserted into the target tumor and the hooks were deployed. The tumor became smaller (35 mm to 25 mm in diameter) in 2 months. CONCLUSION: RFA is an effective and minimally invasive technique to destruct local tumors.     

腹腔镜结直肠癌切除术联合射频消融治疗肝转移癌

目的 探讨腹腔镜结直肠癌切除术+同期RFA治疗肝转移癌的临床价值.方法 2001年12月至2006年7月成都市第三人民医院对22例结直肠癌合并同时性肝转移的患者施行腹腔镜结直肠癌切除术+同期RFA治疗肝转移癌,术后通过增强CT检查评价消融灶固化效果.采用X2检验分析疗效.结果 本组22例患者中8例肝转移癌为多发,16例有合并症.对31个肝转移癌进行RFA治疗,未发生相关并发症;术后平均住院时间为(14±5)d,无手术死亡.5例因消融不完全进行重复RFA,4例消融灶复发(2例重复RFA);6例死亡(2例死于消融灶复发).消融灶复发率为18%(4/22),病死率为27%(6/22).肝转移癌直径≥2.0 cm者RFA后消融灶复发率高于直径＜2.0 cm者(x2=5.867,P＜0.05).结论 腹腔镜结直肠癌切除术+同期RFA治疗肝转移癌,为多发性肝转移癌、合并基础疾病、高龄、手术耐受差和肿瘤切除困难的结直肠癌患者提供了治疗的机会.     

入肝血流阻断下射频消融后毁损灶周围肝组织的病理变化

目的:评估血流阻断射频术后毁损灶周围正常肝脏组织的病理变化。方法:兔VX2肝肿瘤接种成功后分为单独射频组与射频联合入肝血流阻断组(联合射频组)。射频采用冷循环射频消融治疗(参数设定为30 W,8 min),入肝血流阻断采用Pringle法。1周后处死动物,通过HE染色观察术后毁损灶周围肝脏组织的病理变化。结果:与单独射频组比较,联合射频组毁损灶周边正常肝组织内中央静脉及Glisson鞘周围可见大量炎症细胞聚集,且肝细胞肿胀,门静脉、中央静脉扩张、胆管上皮增生等病理变化均更明显(均P<0.05)。结论:血流阻断后射频对毁损灶周围正常肝组织的病理损害较单独射频的损害严重。     

A mathematical model for preoperative planning of radiofrequency ablation of hepatic tumors

Background: Radiofrequency ablation (RFA) is rapidly evolving as an effective minimally invasive technique for the treatment of small and unresectable liver tumors. A potential cause of treatment failure is the inability to determine the optimum number of overlapping ablations needed to completely destroy tumors larger than the size of a single ablation. To clarify this relationship, we performed a mathematical evaluation that enables us to accurately estimate the number of ablations needed to completely ablate larger tumors. Methods: This estimation is based on the assumptions that complete ablation of the surface of a target tumor, including its blood supply, would completely destroy the tumor and that the tumor and ablations produced are perfectly spherical. The smallest possible number of partially overlapping ablations that would completely cover the surface of the target tumor is the same as the number of faces on a regular polyhedron that has a circumscribing diameter equal to or greater than the diameter of the target sphere. Results: This mathematical analysis shows that for a 5-cm ablation device, tumors with diameters ranging between 3.01 and 3.30 cm will require at least four ablations. Tumors between 3.31 and 4.12 cm require six overlapping ablations, and tumors between 4.13 and 6.23 cm require 12 overlapping ablations. The number of ablations needed for larger tumors and for 3-, 4-, 6-, and 7-cm ablation devices are also determined. Conclusion: The smallest number of ablations required to completely ablate a spherical target tumor larger than the size of the ablation sphere increases dramatically as tumor size increases. Because this model is geometrically optimized, even a small change in the position of the ablation spheres with respect to the target sphere can leave potentially unablated tumor and thus result in treatment failure.     

Development of a perfused ex vivo tumor-mimic model for the training of laparoscopic radiofrequency ablation

Background Laparoscopic radiofrequency ablation (RFA) is a safe and effective method for tumor destruction in patients with unresectable liver tumors. However, accurate probe placement using laparoscopic ultrasound guidance is required to achieve complete tumor ablation. This study aimed to develop a perfusable ex vivo tumor-mimic model for laparoscopic radiofrequency ablation training. Methods After rinsing the prepared liver vessels with anticoagulants, porcine livers were perfused. Tumor-mimics were created by injecting a mixture consisting of 3% agarose, 3% cellulose, 7% glycerol, and 0.05% methylene blue, creating hyperechoic lesions in ultrasound. Heparinized porcine blood was used as perfusion medium. Continuous perfusion of the porcine liver was provided by connection of a pump system to the portal vein and the vena cava inferior. Laparoscopic RFA techniques were taught using a laparoscopic pelvi-trainer. Results A total of 30 laparoscopic ablations were performed in four porcine livers. The simulated “tumors” were clearly visible on laparoscopic ultrasound and not felt during placement of the RFA probe. In addition, color duplex ultrasound showed clear signals indicating for a sufficient liver perfusion. Conclusion Laparoscopic RFA requires advanced laparoscopic ultrasound skills for an accurate placement of the RFA probe. The perfused tumor-mimic model presented is a safe, easy, effective, and economic method to improve and train laparoscopic RFA skills on porcine liver tissue.     

Percutaneous ultrasound-guided radiofrequency ablation for kidney tumors in patients with surgical risk

OBJECTIVE: The aim of this study was to describe our experience with percutaneous ultrasound-guided radiofrequency ablation of kidney tumors. METHODS: From July 2002 to August 2005, 45 radiofrequency ablations (RFA) in 42 selected patients with kidney tumor were performed. The patients had either contraindications to surgery procedures or had a solitary kidney. The average tumor size was 37.5 mm (range, 18-59 mm) with the mean age of 68 years (range, 28-83 years). RFA were performed based on radiographic findings. Needle biopsy was made only twice. Monopolar Cool-tip Tyco or bipolar Celon Olympus radiofrequency devices were used. The procedure was performed under conscious sedation with local anesthesia. Treatment efficacy was assessed by computed tomography and by Doppler ultrasound. The absence of contrast enhancement on computed tomography was considered to be a successful treatment. RESULTS: The average follow up was 14 months (range, 3-36 months). In 42 tumors (93%), total absence of contrast enhancement was obtained after the initial RFA and in three tumors (7%) after the second ablation session. There were no complications following 41 procedures, including all ablations in small (<35 mm) renal masses. In four procedures, minor complications were observed. All patients are alive. There has been no need for chronic hemodialysis and, until now, we have not observed any local recurrences with the exception of one metastasis to an ipsilateral adrenal gland. CONCLUSIONS: RFA of kidney tumors is a promising alternative treatment which could be considered for patients who are not suitable for surgery.     

Bimodal electric tissue ablation (BETA) compared with the Cool-Tip RFA system

Background: Bimodal electric tissue ablation (BETA) incorporates the process of electrolysis into radiofrequency ablation (RFA) to increase the size of tissue ablation. This study investigated whether BETA could increase the efficacy of the Cool‐Tip RF system (Covidien, Boulder, CO, USA) to produce larger ablations. It also investigated whether applying electrolysis only during the pretreatment phase (called electrochemical treatment (ECT)/RFA group) is as effective as BETA (where electrolysis was used during both the pretreatment and RFA phases). Methods: A Cool‐Tip RF system (Covidien) was used to test three types of ablations (RFA, BETA, and ECT/RFA) in a pig liver model. In BETA, 9 V of direct current was provided for 10 min, after which the RF generator was started and both electrical circuits were allowed to run concurrently. In ECT/RFA, however, the direct current circuit was switched off after 10 min of pretreatment and only RFA was performed as described above. Ablation sizes were measured in three dimensions. Results: The size of ablations (transverse diameter A and B) produced by BETA and ECT/RFA was significantly larger compared with standard RFA (P < 0/001). BETA also created larger ablations compared with ECT/RFA (P < 0.001). Conclusion: BETA could improve the efficacy of the Cool‐Tip RF system (Covidien) to achieve larger ablations. The increased tissue hydration improved delivery of electrical energy to the tissues and delayed the process of desiccation, thus allowing the ablation process to continue for longer periods of time to produce larger ablations. BETA could be used to treat larger liver tumours more effectively than standard RFA.     

Locoregional recurrences are frequent after radiofrequency ablation for hepatocellular carcinoma

BACKGROUND: Enthusiasm for radiofrequency ablation (RFA) therapy for patients with unresectable hepatocellular carcinoma (HCC) has increased. The data for recurrence after RFA for patients with HCC is not well documented. The purpose of this study was to evaluate tumor recurrence patterns after RFA in patients with unresectable HCC. STUDY DESIGN: Over a 3-year period, 50 patients having RFA for unresectable HCC were identified at a single institution. Medical records and radiologic studies were reviewed and outcomes factors analyzed. RESULTS: Of the entire cohort, 46 patients underwent RFA by a percutaneous approach under CT guidance. Most patients underwent either one (n = 22) or two ablations (n = 23). At the time of this report, 14 patients (28%) were tumor-free by radiologic and biochemical (alpha-fetoprotein) parameters. Eighteen additional patients had persistence of tumor at the ablation site and 14 patients had recurrence in the liver at sites different from the ablation site. An additional four patients had recurrence in extrahepatic sites. Twelve patients underwent orthotopic liver transplantation after RFA. Of these 12, 5 (42%) demonstrated no viable tumor in the explanted liver. Independent predictors of tumor recurrence included tumor size, serum AFP levels, and the presence of hepatitis. CONCLUSIONS: These data suggest that factors such as tumor size should be considered before employing RFA therapy. In addition to treating the primary tumor, other therapies aimed at the liver's inflammatory state might also be important in achieving a durable response after RFA.     

Real-time spectroscopic assessment of thermal damage: Implications for radiofrequency ablation

Radiofrequency ablation (RFA) is an evolving technology used to treat unresectable liver tumors. Currently, there is no accurate method to determine RFA margins in real-time during the procedure. We hypothesized that fiber-optic based spectroscopic monitoring system could detect thermal damage from RFA in real-time. Fluorescence (F) and diffuse reflectance (Rd) spectra were continuously acquired from within the expected ablation zone during canine hepatic RFA using a fiber-optic microinterrogation probe (MIP). The F and Rd spectral feedback were continuously monitored and ablations were stopped based on changes in spectra alone. After each ablation, the MIP tract was marked with India ink and the ablation zone was excised. The relationship of the MIP to the zone of ablation was examined grossly and microscopically. F and Rd spectral changes occurred in three characteristic phases as the ablation zone progresses past the MIP. Phase 1 indicates minimal deviation from normal lives. Phase 2 occurs as the MIP lies within the hemorrhagic zone of the ablated tissue. Phase 3 correlates with complete tissue coagulation. The absolute magnitude of spectral change correlates with the gross and histologic degree of thermal damage. Optical spectroscopy is a technology that allows real-time detection of thermal tissue damage. In this study, both F and Rd spectroscopy accurately defined the advancing hemorrhagic edge of the zone of ablation and the central coagulation zone. These results suggest that F and Rd spectroscopy can be used to create a real-time feedback system to accurately define RFA margins. Presented in part at the 2003 meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, February 27–March 2, 2003.     

单发直径≤3 cm肝肿瘤No-touch射频消融治疗的安全性及近期疗效分析(附50例报告)

目的探讨No-touch射频消融术(radiofrequency ablation,RFA)治疗直径≤3 cm单发肝肿瘤的安全性和疗效。方法 2015年9月至2017年6月采用cooltip电极对直径小于3 cm单发肝肿瘤50例病人进行No-touch RFA治疗。其中,治疗原发性肝癌49例(初发31例、复发18例),转移性肝癌1例。肿瘤平均直径1.8 cm,治疗前、后检查肝功能、增强CT扫描、磁共振检查、超声造影以及细针肝穿刺活检。观察RFA治疗时间、次数和术后住院时间,RFA治疗后的并发症以及肿瘤完全毁损率,并随访病人的生存情况。结果 50例病人共行No-touch RFA治疗51次,其中1例病人1个月内连续治疗2次。每例平均为1.02次;每次治疗时间平均为8.2 min;术后平均住院时间为3.2 d。Notouch RFA治疗后1个月内复查CT或磁共振,单次治疗后的肿瘤完全毁损率为98.0%,甲胎蛋白(AFP)阳性的22例病人在No-touch RFA治疗后6~12个月内有14例转阴,5例明显下降。50例病人随访时间从2015年9月开始至2017年6月止,其总体生存率为100%,术后总体无瘤生存率为90.0%(45/50)。结论 No-touch RFA对直径小于3 cm的单发肝肿瘤的治疗是一种微创、安全有效的方法。     

Radiofrequency thermal ablation of hepatocellular carcinoma before liver transplantation--a clinical and histological examination

BACKGROUND: Radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) is an optional treatment for patients awaiting liver transplantation (LTX). The study evaluates the efficacy of RFA in the explanted liver and its effect on patient outcome. MATERIAL AND METHOD: Forty-seven patients underwent RFA and were listed for transplant between January 1998 and May 2003. The patients were divided into two groups: transplanted and non-transplanted. Both groups were evaluated in terms of tumor characteristics, recurrence, mortality rate, and time on the waiting list. The ablation sites in the explanted livers were examined for percentage of necrosis by Hematoxylin & Eosin (H&E) stain and by TUNEL stain. RESULTS: Transplantation was carried out in 35 patients (74.5%). Ten patients (21.3%) died before transplant or were removed from the wait list, while two patients (4.2%) are still listed. Mortality and tumor-related mortality were significantly higher in the non-transplanted group. The time spent on the waiting list was longer in the non-transplanted patients (350 vs. 186 d average, p = 0.0345). Thirty-eight ablation sites were examined in the explanted livers. The percentage of tumor necrosis by TUNEL staining was 19.6% higher than that reported by H&E staining. After TUNEL staining, 28 sites (73.7%) had more than 90% necrosis, eight sites (21.0%) had 50-90%, and two sites (5.3%) had less than 50% necrosis. CONCLUSIONS: RFA and LTX can be used successfully in HCC patients, and in most cases, tumor necrosis can be achieved with ultrasound-guided RFA. H&E stain tends to under-represent the amount of tumor necrosis on the ablation sites. Survival of RFA patients after LTX is excellent.     

HP05BETA IS BETTER THAN RADIOFREQUENCY ABLATION

Purpose Radiofrequency ablation (RFA) is a popular method of treating unresectable liver tumours by the use of a high‐frequency, alternating electrical current that heats and destroys tumour cells. The size of the ablation produced is limited by localised charring of adjacent tissue that prevents further conduction of the radiofrequency current. To overcome this problem, a Bi‐modal Electric Tissue Ablation (BETA) circuit has been created that adds a direct electrical current to a radiofrequency current. Direct currents attract water to the cathode in biological tissues and this phenomenon is utilised in an effort to prevent tissue charring. The BETA circuit was tested in a pig model. Methods 2 studies have been performed with this new circuit, one to compare sizes of the ablation produced between standard RFA and the BETA circuit. This was followed by a long‐term study to assess associated changes to liver function and pathological changes within the liver. Results Ablations with significantly larger diameters are created with the BETA circuit (49.6 mm +/− SE 3.46 vs 27.78 mm +/− SE 3.37, p < 0.001). Ablations produced by the BETA circuit induced coagulative necrosis within the treated hepatocytes that healed by fibrosis. Significant rises in serum liver enzymes are seen within 24 hours of treatment but these return to normal within 7 days. Treatment with the BETA circuit otherwise appears safe. Conclusions The BETA circuit produces significantly larger ablations than standard RFA. Although larger, the injuries produced behave in a similar manner to standard RFA and it is anticipated that with further refinements, the BETA circuit will become a useful treatment modality for unresectable liver tumours.     

Bimodal electric tissue ablation-modified radiofrequency ablation with a le veen electrode in a pig model

Radiofrequency ablation (RFA) is a method of treating non-resectable liver tumors by use of a high-frequency alternating electrical current. Concerns have been raised as the local recurrence rates following treatment have been reported to be as high as 47%. The size of the ablation is limited by charring of adjacent tissues. It is hypothesized that by hydrating the liver, we can reduce charring, thus producing larger ablations, and that this can be achieved by addition of a direct electrical current to the electrical circuit. Using a pig model, standard RFA control ablations were created in the left lobe of the liver. Ablations using the modified circuit were created in the right lobe. At the end of the procedure, the pig was killed by lethal injection and the liver harvested. From the explanted liver, the diameter of each ablation was measured and the modified ablations were compared with controls using restricted maximum likelihood variance analysis. From 4 pigs, 14 controls and 12 modified ablations were produced. The mean diameter of the controls was 27.78 mm (+/- SE 3.37 mm). The mean diameter of the modified ablation was 49.55 mm (+/- SE 3.46 mm), which was significantly larger than the controls (P < 0.001). This study has shown that by modification of the standard RFA circuit with the addition of a direct electrical current, significantly larger ablations can be produced. By using this technique, the number of ablations required to treat one tumor would be less and it is anticipated this could reduce the rate of local recurrence.     

Radiofrequency Ablation of Invasive Breast Carcinomas: A Phase II Trial

Background Local ablative therapy of breast cancer represents the next frontier in the minimally invasive breast-conservation treatment. We conducted a phase II trial to evaluate radiofrequency ablation (RFA) of invasive breast carcinomas. Methods Consecutive patients from two Mexican Institutions with invasive breast cancers < 4 cm, with no multicentric tumors and no previous chemotherapy were included in this trial. Under ultrasound guidance, the tumor and a 5 mm margin of surrounding breast tissue were ablated with saline-cooled RFA electrode followed by surgical resection. Routine pathologic analysis and viability evaluation with NADPH-diaphorase stain were performed to assess tumor ablation. Procedure-associated morbidity was recorded. Results Twenty-five patients were included. Mean patient age was 55.3 years (range 42–89 years). Mean tumor size was 2.08 cm (range 0.9–3.8 cm). Fourteen tumors (56%) were <2 cm. The mean ablation time was 11 minutes using a mean power of 35 W. During ablation, the tumors become progressively echogenic that corresponded with the region of severe RFA injury at pathologic examination. Of the 25 patients treated, NADPH stain showed no evidence of viable malignant cells in 19 patients (76%), with significant difference between tumors <2 cm (complete necrosis in 13 of 14 cases, 92.8%) vs. those >2 cm (complete necrosis 6 of 11 cases, 54.5%) (P < .05). No significant morbidity was recorded. Conclusions RFA is a promising minimally invasive treatment of small breast carcinomas, as it can achieve effective cell killing with a low complication rate. Further studies are necessary to optimize the technique and evaluate its future role as local therapy for breast cancer.     

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??Current indications and efficacy of radiofrequency ablation in the treatment of liver cancer ZHANG Jie??CHEN Min-shan. Department of Hepatobiliary Surgery??Cancer Center??Sun Yat-sen University??Guangzhou 510060??China
Corresponding author??CHEN Min-shan??E-mail??cms64@163.com
Abstract Radiofrequency ablation (RFA) has been accepted as one of the curative therapies for small liver cancer, following liver resection and transplantation with its development and clinical application in liver cancer over 20 years. The published experts’ statement in China has confirmed the impartment role of RFA in the treatment of liver cancer and defined that RFA can be used as a curative treatment for single tumor ≤5 cm or tumor number ≤3 and each ≤3 cm, and as a palliative or combined treatment for unresectable single tumor >5 cm or multiple tumors >3 cm. Laparoscopic RFA is superior to percutaneous RFA for tumors in unfavorable location. RFA combined with disconnection is an effective treatment for patients with liver cancer and portal hypertension. Combined with transcatheter arterial chemoembolization (TACE), RFA can improve its ablative region, complete ablation rate and prognosis.