Liver Metastases & Microwave Ablation 

Surgery remains the treatment of choice for patients with resectable hepatic tumors. 

However, when there are multiple tumors caused by intrahepatic metastases, multidisciplinary treatments consisting of reduction surgery, microwave ablation, ethanol injection, and intra-arterial chemotherapy might be useful. Non-resectable situations are often improved to resectable ones by use of the newer modalities. Furthermore, in situations where an operation is contraindicated, ablative techniques can still offer the possibility of cure, if other tumor is not present. 

Theoretical studies have suggested that microwave energy can increase the depth of heating compared with radiofrequency energy. Complications would be similar to RFA treatments. 

For the latest update, Search Pubmed for &&url
References for this Section are below.


<b>Liver Metastases & Microwave Ablation 
Selected Medical Journal Article Annotated References</b>
[For the full abstract, use the links provided, or search on Pubmed.  Ed.]


Cancer 2000 Jul 15;89(2):276-84 
<b>Microwave coagulation therapy for multiple hepatic metastases from colorectal carcinoma.</b> 
Shibata T, Niinobu T, Ogata N, Takami M. 
Department of Surgery, Toyonaka Municipal Hospital, Osaka, Japan. 

... Compared with other treatments, microwave coagulation is a relatively less invasive treatment for various kinds of solid tumors. Although its effectiveness in primary hepatocellular carcinoma has been shown, its effectiveness in the treatment of hepatic metastases from colorectal carcinoma has been unclear. The aim of this study was to evaluate its effectiveness in the treatment of multiple hepatic metastases from colorectal carcinoma by comparing this technique with that of hepatic resection. One-, 2-, and 3-year survival rates and mean survival times were 71%, 57%, 14%, and 27 months, respectively, in the microwave group, whereas they were 69%, 56%, 23%, and 25 months, respectively, in the hepatectomy group. The difference between these two groups was statistically not significant (P = 0.83). On the other hand, the amount of intraoperative blood loss in the microwave group (360 +/- 230 mL) was smaller than that in the hepatectomy group (910 +/- 490 mL, P < 0.05). ... Microwave coagulation therapy is suggested to be equally effective as hepatic resection in the treatment of multiple (two to nine) hepatic metastases from colorectal carcinoma, whereas its surgical invasiveness is less than that of hepatic resection. Copyright 2000 American Cancer Society. Publication Types: Clinical trial Randomized controlled trial 
&&url PMID: 10918156


Gan To Kagaku Ryoho 2000 Oct;27(12):1842-5 
<b>[Assessment of colorectal cancer patients exhibiting bilobular multiple hepatic metastases]. [Article in Japanese] </b>
Shibata T, Shimano T, Kitada M, Niinobu T, Fukushima Y, Hata S, Fujita J, Ikeda K, Hayashida H, Takahashi Y, et.al.
Dept. of Surgery, Toyonaka Municipal Hospital. 

We assessed 23 patients who underwent surgical therapy of hepatectomy or microwave coagulation therapy (MCT) for bilobular multiple hepatic metastatic foci following curative resection of the primary lesion of colorectal cancer. .... MCT was considered to be useful local therapy for cancer as the first therapy and as a therapy following recurrence. 
&&url PMID: 11086426 


Radiographics 2000 Jan-Feb;20(1):9-27 
<b>Minimally invasive treatment of malignant hepatic tumors: at the threshold of a major breakthrough. </b>
Dodd GD 3rd, Soulen MC, Kane RA, Livraghi T, Lees WR, Yamashita Y, Gillams AR, Karahan OI, Rhim H. 
Department of Radiology, University of Texas Health Science Center at San Antonio, 78284-7800, USA. 

Six existing minimally invasive techniques for the treatment of primary and secondary malignant hepatic tumors--radio-frequency ablation, microwave ablation, laser ablation, cryoablation, ethanol ablation, and chemoembolization--are reviewed and debated by noted authorities from six institutions from around the world. All of the authors currently believe that surgery remains the treatment of choice for patients with resectable hepatic tumors. However, the clinical results of each of the minimally invasive techniques presented have exceeded those obtained with conventional chemotherapy or radiation therapy. Thus, for nonsurgical patients, these techniques are becoming standard independent or adjuvant therapies. In addition, with continued improvement in technology and increasing clinical experience, one or more of these minimally invasive techniques may soon challenge surgical resection as the treatment of choice for patients with limited hepatic tumor. 
&&url PMID: 10682768 


Endoscopy 2000 Aug;32(8):591-7 
<b>Laparoscopic microwave coagulation therapy for hepatocellular carcinoma. </b>
Seki S, Sakaguchi H, Kadoya H, Morikawa H, Habu D, Nishiguchi S, Shiomi S, Kitada T, Kuroki T. 
Third Dept. of Internal Medicine, Osaka City University Medical School, Osaka, Japan. s.seki@med.osaka-cu.ac.jp 

... Several different effective forms of treatment are available, singly or in combination, for patients with hepatocellular carcinoma (HCC). These include surgical resection, transcatheter arterial embolization, percutaneous ethanol injection, and percutaneous microwave coagulation therapy. In this study, we carried out laparoscopic microwave coagulation therapy (LMCT), using laparoscopic microwave electrodes to treat HCC. ...The mean longest axis of the ... coagulated areas including the nodules was 40 mm, with additional therapy being required in two patients. Complete efficacy of the treatment was observed in 21 patients (87.5%), but local recurrences were seen in three of them one year after LMCT. The three-year survival rate was 92%... Hemostasis was complete, but mild pneumothorax occurred in three patients. ... LMCT under local anesthesia is a minimally invasive and effective therapy when carried out on a single occasion to treat HCCs located near the liver surface, and it can be safely performed under direct visual guidance. 
&&url PMID: 10935786 


Am J Gastroenterol 1999 Jul;94(7):1914-7 
<b>Standards for selecting percutaneous ethanol injection therapy or percutaneous microwave coagulation therapy for solitary small hepatocellular carcinoma: consideration of local recurrence. </b>
Horigome H, Nomura T, Saso K, Itoh M. First Department of Internal Medicine, Nagoya City University Medical School, Japan. 

... Percutaneous ethanol injection therapy (PEIT) and percutaneous microwave coagulation therapy (PMCT) are effective treatments for small hepatocellular carcinoma (HCC). There are no clear standards, however, for the selection of PEIT or PMCT. We determined standards based on local recurrence. ...PEIT was effective for treating well-differentiated HCC, and PMCT was effective for treating HCC measuring < or = 15 mm in diameter. PMCT was superior to PEIT for treating patients with HCC measuring < or = 15 mm in diameter. In such cases with well-differentiated HCC, PEIT was as effective as PMCT. CONCLUSIONS: The selection of PEIT or PMCT to treat patients with HCC should be based on tumor size and cell differentiation. 
&&url PMID: 10406259 


Compiled by doctordee  May 2001

