超声引导联合腹腔镜微波消融治疗特殊部位肝癌的临床体会

目的总结超声引导下联合腹腔镜行微波消融治疗特殊部位肝癌的临床应用价值和体会。方法回顾性分析我院2008年2月至2010年10月期间在超声引导下联合腹腔镜行微波消融治疗的9例肝脏恶性肿瘤患者的临床资料。结果原发性肝癌6例,转移性肝癌3例;多发肿瘤8例,单发肿瘤1例。患者均有1个或多个病灶侵及肝脏被膜,共计13个病灶,其中位于膈顶6个,右叶脏面邻近肠管3个,左叶邻近胃壁2个,胆囊床1个,肝门部1个。患者术后无膈肌损伤、胃肠道穿孔、大出血、胆汁漏等严重并发症发生,围手术期无死亡病例。患者随访(9.2±4.7)个月(4～18个月)。术后1个月行CT检查,11个病灶完全消融,完全消融率为84.6%(11/13);2个(2例)病灶边缘部分残留,其中1例再次行微波消融,1例行无水乙醇消融。术后3个月再次复查CT,4例患者出现新发病灶,其中2例再次行微波消融治疗,1例行无水乙醇消融治疗,1例因合并肺转移而放弃治疗;1例肝功能不佳于术后6个月死于肝功能衰竭;1例多发病灶患者于术后10个月死于肿瘤脑转移;其余患者尚存活。结论超声引导下联合腹腔镜行微波消融治疗特殊部位的肝癌安全、有效、疗效确切。     

腹腔镜下微波消融术治疗肝癌的临床疗效观察

目的:探讨腹腔镜下微波消融术治疗肝癌的临床疗效。方法:自2011年6月共为14例(19个病灶)肝癌患者行腹腔镜下微波消融术。术前行腹部增强CT或B超检查,观察术后并发症、肝功能、AFP等指标,以评估其临床疗效。结果:14例手术均顺利完成。术后发热8例,疼痛10例,无术后出血、胆漏、消化道穿孔等严重并发症发生。1例残留病灶,术后在B超引导下行经皮微波消融治疗;2例新发病灶,均行选择性肝动脉化疗栓塞术治疗,1例死于肝功能衰竭。结论:腹腔镜下微波消融结合了腹腔镜及微波消融的微创特点,患者创伤小,疗效确切,手术安全可行,尤其适于突出肝脏表面及病灶邻近胆囊的患者。     

超声引导下胆囊浆膜层下注射生理盐水辅助微波消融胆囊旁肝肿瘤

目的观察超声引导下胆囊浆膜层下注射生理盐水辅助微波消融治疗胆囊旁肝肿瘤(边缘距离胆囊壁≤5mm)的应用价值。方法回顾性分析13例接受胆囊浆膜层下注射生理盐水辅助经皮微波消融胆囊旁肝肿瘤患者的资料,靶肿瘤边缘距离胆囊≤5mm,治疗后观察并发症情况,并评估消融效果。结果对13例胆囊旁肝肿瘤成功在胆囊浆膜层下注射生理盐水形成胆囊壁水肿后完成微波消融。3例以胆囊浆膜层下注射生理盐水辅助消融治疗胆囊旁3个病灶,再以人工腹腔积液辅助技术治疗肝内其他病灶;2例采用人工腹腔积液法失败后改用胆囊浆膜层下注射生理盐水法辅助完成消融治疗。1例治疗中心率最低至20次/分;1例术后出现应激性胃溃疡;7例术后低热,对症处理后均缓解。治疗后中位随访时间6.2(3～16)个月,8例肿瘤完全消融,2例肿瘤残留,3例肿瘤肝内转移。结论胆囊浆膜层下注射生理盐水冷却保护技术安全、有效,可增加安全消融范围,有利于适形消融胆囊旁肝肿瘤。     

微波消融治疗特殊部位肝脏恶性肿瘤的有效性及安全性

目的 观察微波消融对特殊部位肝脏恶性肿瘤的有效性及安全性。方法 对34例肝脏恶性肿瘤患者的38个病灶行CT和/或超声引导下微波消融治疗，其中毗邻膈肌、毗邻肝包膜各16个，毗邻门静脉一、二级分支3个，毗邻胆囊2个，毗邻肝静脉（下腔静脉旁）1个。消融后1个月复查腹部增强CT或MRI，以改良实体瘤疗效评价标准（mRECIST）评估治疗效果。采用Clavien-Dindo并发症分级法评估并发症。结果 对34例均顺利完成微波消融治疗。术后1个月，腹部增强CT或MRI示37个（37/38，97.37%）消融区域呈边界清晰的低密度/低信号改变，动脉期无明显强化，判定为完全缓解；1个（1/38，2.63%）毗邻下腔静脉病灶可见部分残留，为部分缓解。术后24例出现Clavien-Dindo Ⅰ级并发症，包括20例腹部隐痛、3例恶心及1例呕吐，经对症处理后均缓解；2例出现Ⅱ级并发症，其中感染、发热各1例，予抗生素及退热治疗后好转；1例Ⅲa级并发症，表现为腹腔积液，经腹腔穿刺引流后缓解。结论 微波消融治疗特殊部位肝脏恶性肿瘤安全、有效。     

腔镜下微波消融联合术后经脐静脉插管化疗治疗结直肠癌肝转移

目的探讨腹腔镜结直肠癌切除及脐静脉插管同期微波消融联合术后化疗治疗肝转移的临床疗效。方法在腹腔镜下对1I例结直肠癌肝转移行结直肠癌切除及经肝圆韧带脐静脉插管置泵,同期行肝脏转移瘤微波消融治疗,术后辅以经化疗泵介入化疗。比较治疗前后肿瘤直径大小、血供及坏死情况。结果本组治疗前CT检测转移瘤直径为（4．2±2．5）cm,治疗后为（2．5±1．2）cm,转移瘤结节完全坏死8例（72．7％）。随访时间〉6个月者10例,生存10例;随访时间〉12个月者8例,生存6例。结论腹腔镜结直肠癌切除及脐静脉插管同期微波消融联合术后化疗治疗肝转移的疗效好,值得临床推广。     

微波消融治疗肾脏肿瘤的适应证选择(附17例报告及文献复习)

目的:探讨微波消融治疗肾脏肿瘤的适应证。方法:自2013年4月~2014年7月应用微波消融治疗肾脏肿瘤患者17例,男13例,女4例,平均年龄59.4(42~83)岁。按适应证将患者分为三组,组一6例(高危不耐受常规手术组),组二9例(明确诊断并行微波消融治疗组),组三2例(微波消融姑息治疗组)。所有患者术中均行肿瘤穿刺活检联合微波消融治疗。结果:组一穿刺结果示肾透明细胞癌5例,病理无法明确1例,平均随访(11.5±3.8)(6~16)个月,未见肿瘤复发和转移,合并尿瘘1例。组二穿刺结果示肾透明细胞癌3例,高分化腺癌1例,错构瘤5例,平均随访(5.6±4.2)(1~11)个月,未见肿瘤复发和转移。组三穿刺结果均为肾透明细胞癌,平均随访(9.5±2.1)(8~11)个月,患者术前腰背部VAS疼痛评分为6~8分,术后为0~2分,随访期间1例出现远处转移、肿瘤进展,另1例出现股骨病理性骨折,肾脏复发灶治愈。三组患者平均住院(4.0±1.0)(2~7)d。结论:微波消融可以安全有效地用于高危不耐受常规手术、肿瘤体积较小且术前肿瘤性质不明确以及晚期肾脏肿瘤患者的姑息治疗,联合穿刺活检还可以明确肿瘤性质,帮助患者制定下一步治疗措施,但远期疗效仍需进一步随访观察。     

超声引导下经皮微波消融治疗恶性胸、腹壁肿瘤

目的 观察超声引导下经皮微波消融（MWA）治疗恶性胸、腹壁肿瘤的效果。方法 对11例恶性胸、腹壁肿瘤患者行超声引导下经皮MWA治疗,共治疗14个病灶,腹壁6个,胸壁8个;术后随访,观察治疗效果及不良反应。结果 11例超声引导下MWA治疗均成功,技术成功率100%。术后1个月8例治疗有效,3例肿瘤残存。2例术后出现局部疼痛,经对症治疗后缓解;1例局部脂肪液化,予局部消毒换药1个月后痊愈。未见气胸、肠道损伤、皮肤烧伤等严重并发症。4例术前合并病灶周围神经痛,术后疼痛得到有效控制。术后随访4~28个月,中位随访时间8个月;期间2例失访、2例死亡;至随访终点7例疗效较好,未见复发及转移。结论 超声引导下经皮MWA治疗恶性胸、腹壁肿瘤安全、有效。     

术中多极射频消融在肝脏恶性肿瘤治疗中诊疗体会(附20例病例报告)

目的 探讨术中多极射频消融(RFA)在肝脏恶性肿瘤(特别是消化道恶性肿瘤肝脏转移肿瘤)中的作用、适应症及其安全性.方法 2011年8月至2012年3月,我科共收治应用术中RFA的肝脏恶性肿瘤患者20例.术前影像学发现20例患者的肝脏共有37个病灶;对于直径≤5 cm的病灶采用“一针穿刺,多极消融”的空间布针方案,对于直径＞5 cm的病灶采用“多针穿刺,盐水增强消融”的空间布针射频方案.结果 所有患者均顺利完成手术及RFA治疗,所有患者术后7天复查肝脏增强CT,所有消融病灶均显示为低密度液暗区,19例患者肝脏组织毁损范围超过术前病灶体积.其中直径≤5 cm的肝脏单个射频消融病灶患者13例术后随访2～7个月,肝脏未发现复发病灶.术中针道出血2例,予以缝合止血,余病例未发生腹腔内出血、胆道损伤、针道种植转移、肝功能衰竭等射频消融并发症.结论 射频消融是一种微创治疗,手术联合RFA治疗肝脏恶性肿瘤近期疗效确切,安全性好,适应症广.其远期疗效、与肝脏恶性肿瘤其他治疗方案疗效的比较尚待进一步观察.     

微波消融治疗24例结直肠癌肝转移的临床疗效分析

目的 评价微波消融治疗结直肠癌肝转移的治疗效果.方法 2004年1月至2011年8月超声引导下微波消融治疗结直肠癌肝转移患者24例共70个病灶.男性15例,女性9例,中位年龄66岁(44～78岁).所有病灶的直径均在0.8～5.0 cm,患者总共接受了30次微波消融手术.经皮穿刺微波消融19次共35个病灶;开腹消融11次共35个病灶.定期随访观察消融效果,并采用Kaplan-Meier法进行生存分析.结果 全组无围手术期死亡,相关并发症发生率为6.7%.11次开腹微波消融术术中B超发现45个病灶,多于术前B超发现的38个病灶和CT检查发现的35个病灶.11次开腹微波消融术后1个月病灶均完全坏死,19次经皮微波消融术后1个月的病灶完全坏死率为88.6%(P=0.122).直径≤3.0 cm的病灶坏死率为96.4%,3.1～5 cm的病灶坏死率为85.7%(P=0.212).24例患者全部得到随访,随访时间为18～75个月.术后第3个月和第6个月时,19例经皮消融的患者分别有3例和10例出现肝内新发转移灶,而开腹消融术后复发者分别为0例和1例(P=0.046).全组患者的中位生存期为28个月,1、2、3年生存率分别为83.3%、54.3%、23.3%.结论 开腹微波消融术后较经皮消融早期肝内新发转移灶的发生率较低.微波消融是治疗直径≤5 cm的结直肠癌肝转移的安全有效方法.     

介入和热消融治疗胰腺神经内分泌肿瘤肝转移临床疗效及预后因素分析

目的 评估介入及热消融治疗胰腺神经内分泌肿瘤肝转移的临床疗效及预后因素。方法 回顾性分析2006年5月至2017年12月于复旦大学附属中山医院接受经肝动脉化疗栓塞（TACE）及热消融治疗的45例胰腺神经内分泌肿瘤肝转移病人的临床资料。结果 45例病人中无治疗相关死亡病例。中位总生存期（OS）为60.1（95%CI 14.181~106.086）个月,中位无进展生存时间（PFS）为18.3（95%CI 13.078~23.589）个月。1、3、5和7年总存活率分别为83.8%、65.3%、52.9%和37.0%。TACE的总有效率为71.5%,热消融治疗的总有效率为96.2%。COX多因素分析提示原发病灶切除是总生存期的独立预后因素（HR=0.358,95%CI 0.136~0.9412,P=0.037）,原发病灶切除病人5年存活率为70.9%,而未行原发病灶切除者为32.5%。结论 TACE和热消融治疗对胰腺神经内分泌肿瘤肝转移病人安全有效。     

Local Recurrence After Laparoscopic Radiofrequency Thermal Ablation of Hepatic Tumors

Background: Since we first described laparoscopic radiofrequency ablation (LRFA) of liver tumors, several reports have documented technical and safety aspects of this procedure. Little is known, however, about the long-term follow-up of such patients.Methods: From January 1996 to February 1999, we performed LRFA on 250 liver tumors in 66 patients. Triphasic spiral computed tomographic scanning was obtained preoperatively and at 1 week, and every 3 months postoperatively. Lesion diameter was measured in the x- and y-axes and the volume estimated; 181 lesions in 43 patients for whom computed tomographic scans available were included in the study. The tumor types were as follows: 64 metastatic adenocarcinomas, 79 neuroendocrine metastases, 27 other metastases, and 11 primary liver tumors.Results: One week postoperatively, the ablated zone was larger than the original tumor in 178 of 181 lesions, which suggests ablation of the tumor and a margin of normal liver tissue. A progressive decline in lesion size was seen in 156 (88%) of 178 lesions, followed for at least 3 months (mean, 13.9 months; range, 4.9–37.8 months), which suggests resorption of the ablated tissue. Fourteen definite local treatment failures were apparent by increase in size and change in computed tomographic scan appearance, and eight lesions were scored as failures because of multifocal recurrence that encroached on ablated foci (22 total recurrences). Predictors of failure include lack of increased lesion size at 1 week (2 of 3 such lesions failed), adenocarcinoma or sarcoma (18 of 22 failures; P < .05), larger tumors (failures, M < 18cm³ vs. successes, M < 7cm³; P < .005) and vascular invasion on laparoscopic ultrasonography. By size criteria, 17 of 22 failures were apparent by 6 months. Energy delivered per gram of tissue was not significantly different (P < .45).Conclusions: LRFA has a 12% local failure rate, with larger adenocarcinomas and sarcomas at greatest risk. Failures occur early in follow-up, with most occurring by 6 months. LRFA seems to be a safe and effective treatment technique for patients with primary and metastatic liver malignancies.Presented at the 52nd Annual Meeting of the Society of Surgical Oncology, Orlando, Florida, March 4–7, 1999     

Liver Transplant for Metastatic Neuroendocrine Tumors: A Single-Center Experience in Hungary

Unresectable liver metastases of gastroenteropancreatic neuroendocrine tumors are an accepted indication for liver transplant. Patients undergoing liver transplant because of neuroendocrine tumor liver metastases have similar long-term survival compared with hepatocellular carcinoma; however, recurrence rates are reported to be higher.MethodsWe performed a retrospective analysis of medical records of patients who received transplants for neuroendocrine tumor liver metastases in the Department of Transplantation and Surgery of Semmelweis University between January 1995 and August 2018. The median follow-up period was 33 months.ResultsTen liver transplants have been performed because of neuroendocrine tumor liver metastases during the observed period. Recurrence occurred in 5 cases, and 3 patients died. Estimated 1- and 5-year patient survival rates after transplant were 89% and 71%, respectively. Estimated 1- and 5-year recurrence-free rates were 80% and 43%, respectively. Every patient whose primary tumor was of pancreatic origin or those recipients who had Ki67 index values in the explanted liver higher than 5% had disease recurrence.ConclusionPatient survival and recurrence rates after liver transplant were comparable with the results reported by other centers. In line with previous findings, primary pancreatic neuroendocrine tumors and higher Ki67 index values in the explanted livers were both associated with higher recurrence rates. We believe that an international registry would be helpful to better understand factors leading to tumor recurrence in these cases.     

Prognosis after surgery for multiple endocrine neoplasia type 1-related pancreatic neuroendocrine tumors: Functionality matters

BackgroundMetastasized pancreatic neuroendocrine tumors are the leading cause of death in patients with multiple endocrine neoplasia type 1. Aside from tumor size, prognostic factors of pancreatic neuroendocrine tumors are largely unknown. The present study aimed to assess whether the prognosis of patients with resected multiple endocrine neoplasia type 1-related nonfunctioning pancreatic neuroendocrine tumors differs from those with resected multiple endocrine neoplasia type 1-related insulinomas and assessed factors associated with prognosis.MethodsPatients who underwent resection of a multiple endocrine neoplasia type 1-related pancreatic neuroendocrine tumors between 1990 and 2016 were identified in 2 databases: the DutchMEN Study Group and the International MEN1 Insulinoma Study Group databases. Cox regression was performed to compare liver metastases-free survival of patients with a nonfunctioning pancreatic neuroendocrine tumors versus those with an insulinoma and to identify factors associated with liver metastases-free survival.ResultsOut of 153 patients with multiple endocrine neoplasia type 1, 61 underwent resection for a nonfunctioning pancreatic neuroendocrine tumor and 92 for an insulinoma. Of the patients with resected lymph nodes, 56% (18/32) of nonfunctioning pancreatic neuroendocrine tumors had lymph node metastases compared to 10% (4/41) of insulinomas (P = .001). Estimated 10-year liver metastases-free survival was 63% (95% confidence interval 42%–76%) for nonfunctioning pancreatic neuroendocrine tumors and 87% (72%–91%) for insulinomas. After adjustment for size, World Health Organization tumor grade, and age, nonfunctioning pancreatic neuroendocrine tumors had an increased risk for liver metastases or death (hazard ratio 3.04 [1.47–6.30]). In pancreatic neuroendocrine tumors ≥2 cm, nonfunctioning pancreatic neuroendocrine tumors (2.99 [1.22–7.33]) and World Health Organization grade 2 (2.95 [1.02–8.50]) were associated with liver metastases-free survival.ConclusionPatients with resected multiple endocrine neoplasia type 1-related nonfunctioning pancreatic neuroendocrine tumors had a significantly lower liver metastases-free survival than patients with insulinomas. Postoperative counseling and follow-up regimens should be tumor type specific and at least consider size and World Health Organization grade.     

Laparoscopic radiofrequency ablation of neuroendocrine liver metastases: a 10-year experience evaluating predictors of survival

BACKGROUND: A decade ago we reported the first use of laparoscopic radiofrequency thermal ablation (RFA) for the treatment of neuroendocrine hepatic metastases. This study analyzes our 10-year experience and determines characteristics predictive of survival. METHODS: Eighty RFA sessions were performed in 63 patients with neuroendocrine hepatic metastases in a prospective trial. All patients had unresectable disease with computed tomography (CT) documented lesion and/or symptom progression. Perioperative morbidity, symptom relief, disease progression, and long-term survival were analyzed. Data are expressed as mean +/- standard error of the mean (SEM). RESULTS: There were 22 women and 41 men, age 54.4 +/- 1.5 years followed for 2.8 +/- 0.3 years (range, 0.1 to 7.8). Tumor types included 36 carcinoid, 18 pancreatic islet cell, and 9 medullary thyroid cancer. RFA was performed 1.6 +/- 0.3 years after the diagnosis of liver metastases. Number of lesions treated was 6 +/- 0.5 (range, 1 to 16). Forty-nine patients underwent 1 ablation session, and 14 (22%) had repeat sessions caused by disease progression. Mean hospital stay was 1.1 days. Perioperative morbidity was 5%, with no 30-day mortality. Fifty-seven percent of patients exhibited symptoms. One week postoperatively 92% of these reported at least partial symptom relief, and 70% had significant or complete relief. Duration of symptom control was 11 +/- 2.3 months. CT follow-up demonstrated 6.3% local tumor recurrence. Larger dominant liver tumor size and male gender adversely impacted survival (P < .05). Median survival times were 11.0 years postdiagnosis of primary tumor, 5.5 years postdiagnosis of neuroendocrine hepatic metastases, and 3.9 years post-1st RFA. Survival for patients undergoing repeat ablation sessions was not significantly lower. CONCLUSIONS: This study represents the largest series of neuroendocrine hepatic metastases treated by RFA. In this group of patients with aggressive neuroendocrine tumor metastases and limited treatment options, RFA provides effective local control with prompt symptomatic improvement.     

3.0T闭合式MR引导微波消融治疗肝转移瘤的可行性

目的探讨3.0T闭合式MR仪引导微波消融治疗肝转移瘤的可行性。方法采用3.0T闭合式MR仪引导,对14例肝转移瘤(23个病灶)行微波消融术,记录技术成功率、消融参数、手术时间及并发症,术后1个月评价局部疗效。结果技术成功率100%,术中消融功率(65.65±4.11)W,单病灶消融时间(13.92±6.36)min,总手术时间(68.48±19.50)min。2例(2/14,14.29%)发生少量胸腔积液;未见肝脓肿、膈肌穿孔及黄疸等严重并发症。术后1个月肝转移瘤完全消融率91.30%(21/23)。结论 3.0T闭合式MR仪引导下微波消融治疗肝转移瘤安全、可行。     

Laparoscopic radiofrequency ablation of neuroendocrine liver metastases

We previously reported on the safety and efficacy of laparoscopic radiofrequency thermal ablation (RFA) for treating hepatic neuroendocrine metastases. The aim of this study is to report our 5-year RFA experience in the treatment of these challenging group of patients. Of the 222 patients with 803 liver primary and secondary tumors undergoing laparoscopic RFA between January 1996 and August 2001, a total of 34 patients with 234 tumors had neuroendocrine liver metastases. There were 25 men and 9 women with a mean ± SEM age of 52 ± 2 years who underwent 42 ablations. Primary tumor types included carcinoid tumor in 18 patients, medullary thyroid cancer in 7, secreting islet cell tumor in 5, and nonsecreting islet cell tumor in 4. There was no mortality, and the morbidity was 5%. The mean hospital stay was 1.1 days. Symptoms were ameliorated in 95%, with significant or complete symptom control in 80% of the patients for a mean of 10+ months (range 6–24 months). All patients were followed for a mean ± SEM of 1.6 ± 0.2 years (range 1.0–5.4 years). During this period new liver lesions developed in 28% of patients, new extrahepatic disease in 25%, and local liver recurrence in 13%; existing liver lesions progressed in 13%. Overall 41% of patients showed no progression of their cancer. Nine patients (27%) died. Mean ± SEM survivals after diagnosis of primary disease, detection of liver metastases, and performance of RFA were 5.5 ± 0.8 years, 3.0 ± 0.3 years, and 1.6 ± 0.2 years, respectively. Sixty-five percent of the patients demonstrated a partial or significant decrease in their tumor markers during follow-up. In conclusion, RFA provides excellent local tumor control with overnight hospitalization and low morbidity in the treatment of liver metastases from neuroendocrine tumors. It is a useful modality in the management of these challenging group of patients.     

经肝动脉化疗栓塞联合C臂CT引导微波消融治疗肝癌

目的观察经导管肝动脉化疗栓塞(TACE)联合C臂CT引导微波消融(MVA)治疗肝癌的效果,评价以C臂CT动脉灌注成像评估消融范围的可行性。方法 47例肝癌(63个病灶)接受TACE联合C臂CT引导MVA治疗,于消融后即刻行经动脉插管C臂CT灌注成像判断消融范围,记录技术成功率,比较消融后即刻C臂CT与术后24 h内增强CT所示消融灶最大横径和纵径。术后随访观察治疗效果。结果对63个病灶均顺利完成TACE联合MVA治疗,技术成功率100%。消融术后即刻C臂CT测量消融灶最大横径和纵径分别为(3.44±0.95)cm和(4.13±1.01)cm,术后24 h内增强CT显示最大横径和纵径分别为(3.46±0.95)cm和(4.14±1.02)cm,差异均无统计学意义(P均0.05)。术后2例发生右侧反应性胸腔积液(积液量均100 ml),6例发热,未见其他不良反应。术后1个月,38个2.50 cm病灶完全坏死(38/38,100%);25个≥2.50 cm病灶中,24个完全坏死(24/25,96.00%)。术后随访6～25个月,仅2个病灶局部进展(2/63,3.17%),其余病灶未见进展或复发征象。结论 TACE联合C臂CT引导微波消融治疗肝癌安全有效;C臂CT灌注成像可准确评估消融范围。     

Hepatic Microwave Ablation With Multiple Antennae Results in Synergistically Larger Zones of Coagulation Necrosis

Background: Microwave ablation is a promising treatment for unresectable liver tumors. Unlike radiofrequency ablation, microwave ablation may be performed with multiple simultaneously active antennae.Methods: Microwave ablation was performed in an in vivo porcine liver model by using a single antenna (n = 11) or three antennae in a triangular array, activated either sequentially (n = 11) or simultaneously (n = 13). Lesions were measured and assigned a qualitative shape score.Results: Single-antenna microwave lesions had a mean volume of 7.4 +mn; 3.9 cm³, compared with 14.6 +mn; 5.2 cm³ and 43.1 +mn; 4.3 cm³ for sequential and simultaneous multiple-probe ablations, respectively (P < .001; analysis of variance). Simultaneous lesions were rounder than sequential ablations and were more effective near blood vessels. Simultaneous lesions created with probe separation of 1.7 cm were round and confluent, whereas clefts were present with distances >1.7 cm (P < .001).Conclusions: Microwave ablation has several theoretical advantages over currently available radiofrequency devices. Simultaneous three-probe microwave ablation lesions were three times larger than sequential lesions and nearly six times greater in volume than single-probe lesions. Additionally, simultaneous multiple-probe ablation results in qualitatively better lesions, with more uniform coagulation and better performance near blood vessels. Simultaneous multiple-probe ablation may decrease inadequate treatment of large tumors and decrease recurrence rates after tumor ablation.     

Microwave ablation of liver metastasis complicated by Clostridium perfringens gas-forming pyogenic liver abscess (GPLA) in a patient with past gastrectomy

IntroductionGas-forming pyogenic liver abscess (GPLA) caused by C. perfringens is rare but fatal. Patients with past gastrectomy may be prone to such infection post-ablation.Presentation of caseAn 84-year-old male patient with past gastrectomy had MW ablation of his liver tumors complicated by GPLA. Computerised tomography scan showed gas-containing abscess in the liver and he was managed successfully with antibiotic and percutaneous drainage of the abscess.DiscussionC. perfringens GPLA secondary to MW ablation in a patient with previous gastrectomy has not been reported in the literature. Gastrectomy may predispose to such infection. Even in high-risk patients, empirical antibiotic before ablation is not a standard of practice. Therefore following the procedure, close observation of patients’ conditions is necessary to allow early diagnosis and intervention that will prevent progression of infection.ConclusionPotential complication of liver abscess following MW ablation can never be overlooked. The risk may be enhanced in patients with previous gastrectomy. Early diagnosis and management may minimise mortality and morbidity.