介入性肿瘤学的主要疾病之一是HCC发挥重要作用

StephenW

Liver cancer

One of the main diseases interventional oncology plays a big role in is HCC.

South-East Asia is one of the regions where liver cancer cases are increasing rapidly, said Prof Rosmawati.

According to University Malaya Medical Centre (UMMC) consultant hepatologist Prof Dr Rosmawati Mohamed, three-quarters of HCC cases worldwide are diagnosed within the Asia Pacific region.

Additionally, she said during her presentation on The Disease Burden in Asia at the symposium, South-East Asia is one of the areas where liver cancer is rising rapidly.

While the main cause of liver cancer in Asia is hepatitis B infection, Prof Rosmawati noted that studies in UMMC have shown that HCC cases caused by non-alcoholic steatohepatitis (NASH) – a type of non-alcoholic fatty liver disease (NAFLD) – have more than doubled over the last decade.

The increasing prevalence of NAFLD, she said, is due to our expanding waistlines.

One of the challenges of this trend is that NAFLD-induced liver cancer often presents with significantly less underlying cirrhosis – up to one-third of cases – compared to hepatitis C and B infection, which leads to lower rates of detection during regular screening.

Prof Rosmawati also touched on the various staging systems for liver cancer, in particular, the Barcelona Clinic Liver Cancer (BCLC) system and the Hong Kong Liver Cancer (HKLC) system, which are the two main systems that also recommend treatment options.

Clinicians stage HCC because they want to discuss with patients their prognosis, she explained.

However, the BCLC system, which is commonly used in Asia, limits treatment options, as specific treatments are tied to certain stages, she said.

“In real-life clinical practice, we know that the treatment allocation is extremely complex and we individualise (it) for the patient.”

Addressing the audience of doctors, she added: “What you may want to consider, is that it (the staging system) gives you a good framework on what to do next, but in the end, it may not be necessary to limit the treatment options for each stage.

“Because if you think about it, the primary endpoint that you want to show later on is if there is survival benefit for the patient.

“So, this brings about an important point, that we need to have a multidisciplinary approach for the patient with HCC; the reason being that HCC is a complex disease involving both cirrhosis and the cancer itself.”

Block and kill

The role of interventional oncologists in treating cancer, and HCC in particular, is crucial as only about one-fifth of HCC cases are suitable for surgery or liver transplant, according to senior consultant radiologist Dr Peter Goh Yu-Tang from Singapore’s Mount Elizabeth Hospital.

There are a number of methods that interventional oncologists can employ to help manage HCC.

One of these, transarterial chemoembolisation (TACE), was addressed by Prof Dr Chung Jin Wook from Seoul National University’s Department of Radiology in South Korea, in his presentation on cTACE in HCC: Indication, Case Selection, Evidence & Outcome.

While TACE is recommended for only one stage in both the BCLC and HKLC systems – the intermediate stage and stage 3 respectively – Prof Chung noted that a study involving 40 centres worldwide showed that TACE was the leading initial treatment choice, used for patients with various stages of HCC.

“So, we can see that there is a remarkable discrepancy between guideline recommendations and real-life practice.”

He added: “The number one reason for this discrepancy is that TACE has already been recognised as the secondline curative modality for all stages of HCC.

“If you perform TACE very precisely, you can achieve complete tumour necrosis (death) in at least more than half, and up to 80%, of cases.”

The second reason, he said, was because TACE is widely recognised as a safe and effective treatment option.

There are currently two types of TACE treatments.

Conventional TACE (cTACE) utilises a gelatin sponge soaked with chemotherapy drugs to both block off the arteries supplying the tumour and kill it via chemotherapy, while drug-eluting bead TACE (deTACE) uses special beads containing the chemotherapy drugs that slowly release the drugs over a number of days to treat the tumour.

The latter was tackled by the director of Kaohsiung Chang Gung Memorial Hospital’s Department of Diagnostic Radiology and Cancer Centre in Taiwan, Prof Dr Cheng Yu Fan, in his talk on Drug Eluting Bead in HCC.

Based on studies in his hospital, he reported: “cTACE has an almost 60% three-year survival rate, while deTACE is 73.5%, which seems to be very good.

“Of course, stage 1 and stage 2 (HCC) is a little bit better (in terms of survival), but I can tell you that stage 3 has the most benefit because it has almost double the survival time – from 35% to 63% – especially as stage 3 is the disease of big tumours and small vascular invasion.”

He added that using deTACE also reduced the cancer by a stage in 75.6% of cases by decreasing the size and number of tumours. This then allowed the option of surgery to remove the remaining tumours.

Another type of transarterial embolisation uses alcohol, instead of chemotherapy drugs.

This was covered by Chinese University of Hong Kong Department of Imaging and Interventional Radiology chairman Prof Dr Simon Yu Chun Ho in his presentation on Transarterial Alcohol Embolisation in HCC.

“We don’t know of any another agent of similar potency to alcohol when it comes to arteriovenous malformations.

“So, how about using alcohol to treat liver cancers? If you look at their vascularity, they are comparable to arteriovenous malformations,” he said.

He explained that the ethanol-lipiodol mixture typically used in this procedure is a blend of bland embolisation to cut off blood supply to the tumour and chemical ablation to destroy the tumour itself.

“We believe that there is a synergistic effect as embolisation causes tissue ischaemia, which would enhance diffusion of alcohol to the ischaemic cells, and the ablative effect of the ethanol would cause coagulative necrosis (a type of cell death) and further enhance the ischaemia,” he said.

However, this procedure is limited to certain types of patients, including those with well-defined hypervascularised tumours and good liver function, especially as alcohol is very toxic to normal liver cells.

Destroying tumours

For early stage HCC, one of the options is ablation.

In comparison with surgery, this treatment has lower morbidity, a shorter hospital stay, faster recovery and is cheaper overall, said Dr Goh. “And the key point is that liver tumours tend to recur – that is the nature of the beast we are fighting – because there is background liver cirrhosis, and therefore, any liver cell can become malignant.

“The beauty of local ablation is that it is highly repeatable,” he said.

Dr Goh, who is the clinical director of Mount Elizabeth’s Depart-ment of Radiology, explained: “Local ablation refers to focal destruction of the tumour by placing an appliance or a device under image guidance.”

Ablation can be achieved through extreme heat, which includes radiofrequency ablation (RFA) and microwave ablation (MWA), high-intensity focused ultrasound, and extreme cold via cryoablation.

In his talk Radiofrequency & Microwave Ablation in HCC: An Optimal Choice in Early & Intermediate Stage Disease? during the symposium, Dr Goh focused on the first two.

“As we know, RFA is the only ablative technique that actually improves the survival rate. It is effective and relatively cheap,” he said.

Basically, the technique involves delivering an electric current directly to the tumour in the form of radiowaves, which causes the molecules to oscillate. The oscillation creates friction, which results in heat, and heat causes cell death.

However, due to the limited range of the radiowaves, RFA works best in small tumours, with a 95% rate of complete ablation in tumours two centimetres or less in diameter, according to Dr Goh.

For tumours between two to five cm, he said that he uses RFA devices that have multiple electrodes or combines RFA with TACE.

MWA works on a similar principle to RFA, but the microwaves directed into the tumour via an antenna agitate the water molecules in the cells, resulting in friction, heat and cell death.

“Overall, both are extremely effective, but it seems that MWA has better results with the larger tumours – those up to about five cm,” he said.

The MOSM was held recently in Subang Jaya, Selangor, over four days, including a pre-symposium masterclass in cTACE.

It was organised by a multidisciplinary clinical team from Subang Jaya Medical Centre (SJMC).

StephenW

肝癌

介入性肿瘤学的主要疾病之一是HCC发挥重要作用。

Rosmawati教授说，东南亚是肝癌病例快速增长的地区之一。

据马来亚大学医学中心（UMMC）咨询肝病专家罗斯马维蒂·穆罕默德博士，全球四分之三的HCC病例在亚太地区被诊断出来。

此外，她在介绍亚洲疾病负担研讨会时说，东南亚是肝癌迅速崛起的领域之一。

虽然亚洲肝癌的主要原因是乙肝感染，罗斯马维蒂教授指出，UMMC的研究表明，非酒精性脂肪性肝炎（NASH） - 一种非酒精性脂肪性肝病（NAFLD）引起的HCC病例有在过去十年中翻了一番多。

她说，NAFLD日益普及，是由于我们的腰围不断扩大。

这种趋势的挑战之一是，与丙型肝炎和乙型肝炎感染相比，NAFLD诱导的肝癌经常呈现出显着较低的基础性肝硬化（高达三分之一的病例），这导致常规筛查期间检测率较低。

Rosmawati教授还介绍了各种肝癌分期系统，特别是巴塞罗那诊所肝癌（BCLC）系统和香港肝癌（HKLC）系统，这两个系统也是推荐治疗方案的两个主要系统。

她解释说，临床医生希望与患者讨论他们的预后。

然而，亚洲常用的BCLC系统限制了治疗方案，因为具体治疗方法与某些阶段有关，她说。

“在现实生活临床实践中，我们知道治疗分配是非常复杂的，我们为患者个性化（”）。

她补充说：“你可能想要考虑的是，它（分期系统）给你一个很好的框架，接下来要做什么，但最后可能没有必要限制治疗每个阶段的选项

“因为如果你考虑这个问题，那么以后要显示的主要终点是如果患者有生存的好处。

“所以，这带来了一个重要的一点，我们需要对HCC患者采取多学科的方法;原因是HCC是涉及肝硬化和癌症本身的复杂疾病。“

阻止和杀死

根据新加坡伊丽莎白公院医院的高级顾问放射科医师Peter Goh Yu-Tang博士，介入性肿瘤学家在治疗癌症和特别是肝癌方面的作用至关重要，因为只有约五分之一的HCC病例适用于手术或肝移植。

介入性肿瘤学家可以采用多种方法来帮助管理肝癌。

其中之一，动脉化疗栓塞（TACE），由韩国首尔国立大学放射科中心副教授锺金华博士在HCC介绍cTACE：指征，病例选择，证据与结果等方面提出。

虽然TACE推荐在BCLC和HKLC系统中只有一个阶段 - 中间阶段和阶段3 - 钟教授指出，一项涉及全球40个中心的研究表明，TACE是主要的初始治疗选择，用于各种阶段的患者的HCC。

“所以，我们可以看到指南建议和现实生活实践之间存在着显着的差异。”

他补充说：“这个差异的首要原因是，TACE已被公认为HCC所有阶段的二线治疗方式。

“如果您非常精确地执行TACE，您可以在至少一半以上，多达80％的病例中实现完全的肿瘤坏死（死亡）。

他说的第二个原因是因为TACE被广泛认为是安全有效的治疗方案。

目前有两种类型的TACE治疗。

常规TACE（cTACE）利用浸入化疗药物的明胶海绵来阻断供体肿瘤的动脉，并通过化学疗法杀死它，而药物洗脱珠TACE（deTACE）则使用含缓释药物的化学药物的特殊珠粒多天治疗肿瘤。

后者由高雄长庚纪念医院台湾诊断放射科及癌症中心主任郑玉帆博士在HCC药物洗脱珠的讲座中处理。

根据医院的研究，他报告说：“cTACE的三年生存率几乎达到了60％，而deTACE则为73.5％，似乎非常好。

“当然，第一阶段和第二阶段（HCC）有一点好处（就生存而言），但是我可以告诉你，第3阶段最有利，因为它几乎是生存时间的两倍 - 从35％到63 ％ - 特别是第3期是大肿瘤和小血管入侵的疾病。

他补充说，通过减少肿瘤的大小和数量，使用deTACE还可以将癌症减少到75.6％的阶段。这样可以选择手术去除剩余的肿瘤。

另一种类型的动脉栓塞使用酒精，而不是化疗药物。

香港中文大学影像与介入放射科主任何俊春教授介绍了HCC的动脉栓塞栓塞问题。

“关于动静脉畸形，我们不知道任何其他与酒精相似效力的药物。

“那么用酒精来治疗肝癌呢？他说，如果你看他们的血管，他们可以与动静脉畸形相媲美。

他解释说，该方法中通常使用的乙醇 - 碘油混合物是平坦栓塞的混合物，以切断对肿瘤的供血和化学消融以破坏肿瘤本身。

“我们认为，栓塞引起组织局部缺血会增加酒精对缺血细胞扩散的协同作用，乙醇的消融作用会导致凝血性坏死（一种细胞死亡），进一步增强局部缺血， “ 他说。

然而，该方法仅限于某些类型的患者，包括具有明确的血管新生肿瘤和良好肝功能的患者，特别是因为酒精对正常肝细胞毒性很大。

破坏肿瘤

对于早期HCC，其中一个选择是消融。

Goh博士说，与手术相比，这种治疗发病率较低，住院时间缩短，恢复快，整体更便宜。 “关键是肝肿瘤往往会复发，就是我们正在战斗的野兽的性质 - 因为有肝硬化背景，因此任何肝细胞都可能变成恶性肿瘤。

他说：“局部消融的优点是高度可重复。

伊丽莎白伊丽莎白医院放射科临床主任的Goh博士解释说：“局部消融是指通过将器具或器械放置在图像引导下进行肿瘤的局部破坏。

消融可以通过极端热量实现，包括射频消融（RFA）和微波消融（MWA），高强度聚焦超声，以及通过冷冻消融的极端冷。

在他的讲话中，HCC中的射频和微波消融：早期和中期疾病的最佳选择？在研讨会期间，Goh博士着重研究了前两项。

“我们知道，RFA是唯一可以提高存活率的烧蚀技术。这是有效和相对便宜的，“他说。

基本上，该技术涉及以无线电波形式将电流直接传递到肿瘤，这导致分子振荡。振荡产生摩擦，导致热量，热量导致细胞死亡。

然而，由于无线电波范围有限，RFA在小肿瘤中效果最好，直径为2厘米或更小的肿瘤的完全消融率为95％。

对于两到五厘米之间的肿瘤，他说他使用具有多个电极或RFA与TACE组合的RFA装置。

MWA的工作原理类似于RFA，但是通过天线引导到肿瘤中的微波会搅动细胞中的水分子，导致摩擦，发热和细胞死亡。

“总的来说，两者都是非常有效的，但是似乎MWA具有更好的结果，较大的肿瘤 - 高达约5厘米，”他说。

MOSM最近在雪兰莪的Subang Jaya举行了四天，其中包括cTACE的研讨会大师班。

它是由Subang Jaya医疗中心（SJMC）的多学科临床团队组织的。

StephenW

http://www.star2.com/health/2017 ... e-way-in-treatment/