During 3 decades postoperative survival and morbidity and mortality rates for HCC has been dramatically improved and hepatectomy has became golden standard for HCC. Recently ablation therapy such as ethanol injection therapy (PEI), microwave tissue coagulation therapy (MCT) and radiofrequency therapy (RF) has been widely used as a local therapy because of less invasiveness.
According to nationwide survey of The Liver Cancer Study Group of Japan hepatectomy for a solitary HCC greater than 2 cm in all clinical stage showed higher survival rates than PEI or TAE. Only few randomized control studies were reported for evaluation of effectiveness of therapies. RF and MCT result in higher rate of complete necrosis than PEI. However, no RCT study has been reported between hepatectomy and ablation therapy, and it should be needed for choice of appropriate treatment.

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Hepatocellular carcinoma (HCC) is a unique malignancy. Only those with chronic HCV and HBV infection, aflatoxin B₁ intoxication and hemochromatosis are known to develop HCC. Furthermore, HCC is only complicated when these liver diseases are advanced. Owing to the recent progress in the treatment, primary tumors are largely destroyed, and a recurrence from primary sites has become rare. However, many patients suffer from an ectopic recurrence. Most patients die after several episodes of a recurrence. Future management of HCC should be directed toward prediction and inhibition of HCC. Detection of irregular regeneration, an initial step of liver carcinogenesis, by liver biopsy, is most reliable to predict HCC. Treatment aiming at inducing SVR (sustained biological response) or SBR (sustained biochemical response) seems most promising to block the development of HCC.

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Since microwave tissue coagulator became commercially available in 1982, it has been widely used for treating hepatomas. Some gynecologists did use the apparatus in laparoscopic salpingectomy for tubal pregnancy, tubal cautery for sterilization, and hemostasis during biopsies of the ovary and commented on its usability. However, gynecologists effectively forgot about microwave coagulation therapy until a 1995 report of microwave endometrial ablation for menorrhagia. Microwave coagulation therapy or microwave ablation therapy has gained recognition as a minimally invasive alternative to hysterectomy for menorrhagia, and recently a curved microwave applicator extended its indication. Menorrhagia in an enlarged distorted uterine cavity caused by myomas and adenomyosis is treatable by microwaves. In addition, atypical endometrial hyperplasia and early endometrial carcinoma are now within the scope of microwave ablation therapy.

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MR is an useful imaging technique with the ability of delineating real time internal architectural change in multiple imaging planes simultaneously. Since vertical open MR is available at our university, we used microwave to ablate 130 liver tumor, 5 pelvic tumor and one locally recurrent thyroid tumor. The benefits of MR mapping are 1) to be able to treat tumors that cannot be visualized in the other method 2) to delineate internal architectural change during treatment 3) to be able to differentiate treated and untreated area 4) to make adjusted treatment plan during treatment session. This technique has unique potential to be applied to the different area of the body in the near future.

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Microwave has been used to ablate liver tumor for 15 years, however, there was no imaging technique that monitor the effect during the treatment until recently. Since application of MR space mapping technique by the open vertical MRI, we could delineate real time internal architectural change in multiple imaging planes simultaneously. We have successfully treated thyroid cancer local recurrence with this approach. In the article we will review the technique and short term outcome.

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Microwave has been used to ablate liver tumor for 15 years, however, there was no imaging technique that monitor the effect during the treatment. Since application of MR space mapping technique by the open vertical MRI, we could delineate real time internal architectural change in multiple imaging planes simultaneously. We have successfully treated locally advanced pelvic tumors with this approach. In the article we will review the technique and short term outcome.

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Microwave endometrial ablation (MEA) is a new treatment for the patients with hypermenorrhea. MEA is less invasive and safen than hysterectomy.
We performed MEA for 8 patients (39 to 51 year-old Japanese women) with hypermenorrhea using a curved applicator. The endometrium was observed by the hysteroscope before and after MEA to confirm ablation. The four points of endometrium were ablated by microwave (1 point : 70W, 50sec.). No complications of MEA were observed.
After MEA, no menstruation has come on the half of patients with hypermenorrhea, and the others have experienced minor menstrual bleeding. Concerning with dysmenorrhea, one patient has felt no change after MEA, but some patients improved their symptoms.
MEA is an easy, effective and safe treatment for women with hypermenorrhea.

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We performed microwave coagulation to repair the cut pleural surface for a resected lung experimentally, as an alternative method for spontaneous pneumothorax. We found that the pleura was accumulated by microwave coagulation, but not burned. A water sealing test was used to confirm the repair of the ruptured site of the pleura.
Materials and methods : Seven cases of pneumothorax had been admitted for dyspnea. Thoracoscopic microwave coagulation therapy was performed by inserting a throcar of 2 mm in diameter. Using microwave tissue coagulation at the power of 35 W for 30 second, one or more pulmonary bullae of the apex was coagulated thoracoscopically.
Results : We evaluated the serum C-reactive protein between the patients who received microwave coagulation and those treated with the popular automatic stapling device method. The microwave coagulation therapy group showed less C-reactive protein than automatic stapling device group.
Conclusion : Microwave coagulation therapy could be an alternative method to automatic stapling devices for small sized bullae of pneumothorax.

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The possibility of MR-guided multi-channel microwave thermocoagulation therapy was examined. Although extension cables and notch filters were required to use a microwave coagulator under MR environments, sufficient output power was obtained at four individual electrodes. New application software for multi-slice MR temperature monitoring was also prepared on an external PC. Flexible slice setting, calculation of temperature changes using corresponding base-line data and display of multi-slice temperature maps were enabled with this application. Simultaneous ablation with 4 electrodes at the corners of 20 mm square for 6 minutes caused 35 × 35 × 30 mm spherical coagulation area in beef liver. The area with temperature increase by over 40 degrees on the multi-slice MR temperature maps was in a good agreement with this coagulated area of the liver. MR-guided multi-channel microwave coagulation with multi-slice MR temperature monitoring will be one useful application for the clinical use.

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As an aid in more accurate determination of the location of the tip of a microwave electrode for deep site coagulation in the laparoscopic local ablation treatment of liver cancer, we added figures indicating the distance from the tip to the side of the scale. This slight improvement facilitated the evaluation of the insertion length of the electrode from the liver surface. This improved type electrode may be also useful for percutaneous treatment.

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We developed a new microwave electrode with curved antenna for the purpose to achieve “enveloping coagulation” on microwave coagulation therapy more easily. “Enveloping coagulation” means, we named, coagulation process that enveloping coagulation should be done around tumor first and center coagulation next.
The property of new microwave electrode with curved antenna was almost as same as that of original electrode with straight antenna but coagulation area was curved.
As the result, a new microwave electrode would be thought very useful to perform “enveloping coagulation” more easily.
A case of liver cancer treated with a new microwave electrode was reported.

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Recently, endoscopic stenting for the malignant biliary obstruction have contributed to improvement in quality of life (QOL) patients with unresectable pancreato-biliary carcinoma. However, the early occulusion of the stent, due to a bile encrustation, the tumor ingrowth and overgrowth are a major prognostic factor in patients under palliative treatment. In the attempt to prolong the patency of the bile duct, we performed endoscopic microwave coagulation therapy (EMCT) for the malignant biliary obstruction.
There were 26 cases (13 men, 13 women ; mean age 72 years, range 30 to 96 years) including 20 of bile duct carcinoma, 2 cases of the carcinoma of the Vater papilla and 2 cases of the recurrence of the post operative biliary tract carcinoma. The microwave irradiation of 50 W/10-second or 40 W/15-second was delivered to the carcinoma under cholangioscopy or duodenoscopy.
There were no severe complications associated with this procedure. The long-term patency (mean 18 months) of the biliary obstruction was achieved in all cases after the treatment ; An 1 year-patency rate were 38.5%. There out of 19 cases (73%) survived for more than one year without jaundice. The EMCT has a beneficial effect on maintaining patency of the bile duct for the treatment of malignant biliary obstruction, resulting in prolonging the patient survival.

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In our institute, laparotomic microwave coagulation therapy (MCT) is indicated for patients with hepatocellular carcinoma (HCC) and severe liver dysfunction, with HCC which is present in a difficult location to perform centesis percutaneously, and advanced HCC. Cumulative 1-, 3-, and 5-year survival rates in the laparotomic MCT therapy group were 87, 68, 39% respectively. Cumulative 1-, 3-, and 5-year tumor-free survival rates in the laparotomic MCT therapy group were 68, 42, 23% respectively. Although outcome of laparotomic MCT for HCC is entirely poorer than that of partial resection, the outcome of laparotomic MCT therapy is similar to that of partial resection therapy, limiting to the cases with severe liver dysfunction, severe cirrhotic liver, advanced HCC, recurrent HCC, and severe preoperative complication.
Limiting to cases with advanced HCC, severe liver dysfunction, and serve preoperative complication, we believe that laparotomic MCT is the option of surgical treatment for HCC as well as partial resection.

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The treatment of recurrent HCC after hepatectomy is restricted by anatomical changes and reduced hepatic function reserve. In this point of view, MCT under laparotomy and thoracoscopy (MCT-OP) appears a suitable therapeutic method, because it enables total necrosis of recurrent HCC with a minimum risk to the patients. From April 1998 to August 2003, fourteen who developed HCC recurrence in the remnant liver after hepatic resection were treated MCT-OP. Two (14.3%) had a tumor larger than 4 cm in diameter, and 3 (21.4%) had more than 4 in recurrent numbers. Major complication, biloma, occurred in only one case. No local recurrence was seen with all of the cases, but 5 had recurrence at the other regions in the liver. One patient had pulmonary metastasis and was treated by partial lung resection. Twelve patients are alive to date, while the remaining two died of multiple HCC recurrence. In conclusion, MCT-OP is an effective and safe treatment for patients who developed recurrent HCC after hepatectomy.

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Although intrahepatic cholangioma is a poor prognostic disease, no effective therapy has been established without hepatic resection. We have treated total 52 patients with intrahepatic cholangioma from April 1989 to November 2002. Twenty-nine patients underwent hepatic resection, 5 patients with unresectable intrahepatic cholangioma underwent open MCT, and 18 patients underwent exploratory laparotomy or no operation. One-year and 2-year survival rates in open MCT group were 80% and 26.7%, respectively. These were slightly higher than those of non-curative resection group and no operation group. Local recurrence of treated area was experienced in only one case. We conclude that the open MCT is one of an effective therapeutic method for the patient of unresectable intrahepatic cholangioma as a multimodal therapy combined with chemotherapy and irradiation.

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Thirty-five patients with 53 nodules (HCC/Meta = 35/18) were treated with radiofrequency ablation (RFA) using RITA Model 90 device. Model 90 has nine hook-shaped expandable electrode tines with a maximum deployment diameter of 5.0 cm. 37 nodules were treated with RFA alone. 6 nodules ware treated with combination of RFA and occlusion of both hepatic artery and portal vein. 5 nodules were treated with a combination of RFA and chemoembolization. The thermal areas using an electrode with a 4 cm deployment and 5 cm deployment (4 cm : 48.0 × 44.9 mm, 5 cm : 52.1 × 47.7 mm) were significantly larger than those using an electrode with a 3 cm deployment (38.7 × 32.6 mm). The thermal areas treated by combination therapy were larger than those treated RFA alone. Our experience suggests that RFA with Model 90 is effective in the treatment of hepatic tumor equal to or smaller than 35 mm, and RFA with occlusion of blood flow is effective for tumors larger than 35 mm.

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Background : Microwave coagulation therapy (MCT) is beginning to be established as less invasive therapy, has been widely applied local ablation therapy for liver tumors. However, the indications for MCT for liver metastases remain controversial. We have examined the possibility of the MCT for the liver metastases.
Material and Methods : Open MCT (OMCT) was performed 12 nodules in 6 patients. Intraoperative ultrasonography was used in every case for monitoring lesion and therapeutic effect. Focally recurred 4 out of 12 nodules, among them, 2 nodules underwent hepatic resection, which were used as subject to conduct an examination on the recurrence form and diagnostic character on diagnostic imagings, as well as the pathological analysis.
Results : It was diagnosed that until one month after the OMCT, all of the treated 12 nodules became necrotic on dynamic CT scan. It was confirmed that 2 out of 12 nodules (17%) had recurrence on the treated area, and 2 nodules (17%) had recurrence peripheral of the treated area. In the recurrence cases, the tumor marker did not normalized but increased again. In the case of recurrence on the treated area, residual and locally recurrent cancer cells were found in the necrotic tissues, and they were infiltrating surrounding tissues. In the case of recurrence peripheral of the treated area, cancer cells were not found in the necrotic tissues, there were connective tissues between the necrotic tissues and the cancer tissues. In the 2 cases of hepatic resection, there have been no reccurrence 16 month and 9 month after the resection.
Conclusion : At this point, in view of its difficulty of making judgement on the effectiveness of the treatment and the risk of local recurrence, it is necessary to limit the adaptation of MCT against liver metastases only to hepatic resection case or high risk cases.

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Twenty-five patients with solitary HCC were firstly treated by laparoscopic microwave coagulation (LMC), 14 were also treated by percutaneous microwave coagulation (PMC), 5 were also treated by laparoscopic radiofrequency ablation (LRFA), and 28 were also treated by percutaneous radiofrequency ablation (PRFA). For these 72 cases, we analyzed the survival rates and compared the rates among LMC, PMC, and PRFA group. Three-year survival rates were 91% in LMC group, 92% in PMC group, and 96% in PRFA group. The differences of survival rates were not statistically significant among LMC, PMC, and PRFA group. Next, we analyzed disease-free survival rates among LMC, PMC, and PRFA group. 3-year disease-free survival rates were 31% in LMC group, 22% in PMC group, and 41% in PRFA group. The differences of disease-free survival rates were not statistically significant among LMC, PMC, and PRFA group. The therapeutic efficacy is thought to be equal between microwave coagulation and radiofrequency ablation.

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Laparoscopic hepatic resection was less invasive than open hepatic resection, that was own to microwave tissue coagulation for a control of intraoperative bleeding. Microtaze^® was very useful in laparoscopic hepatic resection for the treatment of HCC localized near the surface in left hepatic lobe.

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A 70-year old female was referred to department of surgery because of a liver tumor which was identified by CT scans. Both CT scans and MRI of the liver revealed small HCC in the S_4a of the liver. Because she has been suffered from chronic renal failure and liver cirrhosis with type C chronic hepatitis, a hand-assisted laparoscopic surgery (HALS) was selected for minimal invasive therapy.
Under HALS a hepatectomy of S_4a of the liver was performed and enough range of the surgical procedures and some essential management, such as the maneuver of the liver for control of bleeding were ensured. Then the operation was accomplished safely without any complications. Laparoscopic hepatectomy seems to be useful for small tumors on some limited sites especially under HALS.

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We reported two cases of thoracoscopic radiofrequency ablation therapy for hepatocellular carcinoma. Thoracoscopic therapy was indicated for tumors located in segment 8 or 7 of the liver beneath the diaphragm. This location was difficult to reach by a percutaneous or laparoscopic approach. In one case, tumor puncture was performed using intraoperative ultrasound through the diaphragm. In another case, the puncture was performed directly to incise the diaphragm by Harmonic Scalpel™, since to the tumor was exposed to the liver surface. In both cases the surgical margin was adequate at least 5 mm. In conclusion, thoracoscopic radiofrequency ablation therapy is a safe, effective treatment for unresectable hepatocellular carcinoma with liver cirrhosis.

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Partial nephrectomy without renal vascular clamping using microwave tissue coagulator (MTC) was performed for 8 renal tumors in 7 patients between January 2001 and February 2003. Tumor diameter ranged 1.0 to 2.3 cm (median 1.4 cm). Initial 2 cases underwent open partial nephrectomy using MTC. The other 6 cases underwent endoscopic partial mephrectomy using MTC. Median operating time of these 6 cases was 210 min (range 195-530 min). Histological examination revealed renal cell carcinoma in 7 cases and angiomyolipoma in one case. Surgical margin was negative in all cases. Urinary fistula was observed in one case as a complication, however this urinary fistula was spontaneously closed on the 13th postoperative day. MTC seems to be a safe and effective modality in partial nephrectomy for small renal tumors with normal renal tissue between collecting system.

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We performed retroperitoneoscopic partial nephrectomy using microwave tissue coagulation without renal pedicle clamping. This procedure can be expected to be minimally invasive with minimal bleeding, while preserving renal function. However, this surgical procedure should be carefully selected for patients with tumors less than 2 cm in diameter, peripherally located, and with a distance of more than 1 cm between the tumor and the renal collecting system.

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Between 1987 and 2002, 63 partial nephrectomy, including 34 open surgeries with renal hilar clamping (Group O), 9 open surgeries without hilar clamping and 20 laparoscopic surgeries without hilar clamping using a microwave tissue coagulator (Group L), were performed. Although operative time in Group L was significantly longer than that in Group O, postoperative hospital stay was shorter in Group L than Group O. Early and late complication rate and preserved renal functions improved with experience in Group O. Although in Group L late complication rate and preserved renal functions were better by experienced surgeons, early complication rate was not. A microwave coagulator is promising apparatus in minimally invasive treatment for small renal tumors, however, technical improvements, including monitoring and preventions for heat injury, are necessary for a widespread use of this apparatus.

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The feasibility and indication of laparoscopic partial nephrectomy for small, organ confined renal cell carcinoma (RCC) was discussed. From October 1999 to April 2004, 10 patients, who were defined as “elective” cases with normal ipsilateral kidney, underwent laparoscopic partial nephrectomy in our institute. All procedures were performed transperitoneally without clamping renal vessels. Renal parenchyma was resected with bipolar forceps in first 4 cases. In last 6 cases, microwave tissue coagulator (Microtaze^®) was utilized for coagulating renal parenchyma around the tumor prior to transaction with scissors. All procedures were completed successfully without open conversion and no major complication was observed. Estimated blood loss was significantly decreased in last 6 cases in which Microtaze^® was used than initial 4 cases (104.2 mL vs.1,586.2 mL). Our data indicate that Microtaze^® is a useful tool for laparoscopic partial nephrectomy with superior capability of hemostasis. However, to reduce some reported complications, such as postoperative urine leakage and excessive renal infarction, critical selection of the patients should be important.

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Open partial nephrectomy for small renal tumors without renal ischemia using microwave was investigated. 11 patients with small renal tumors underwent open partial nephrectomy without pedicle clamping. 7 cases of all were male and 4 were female, and mean age was 59.5 years. 9 cases were elective cases and two were imperative cases. Staging of AII was pT1N0M0.
All cases had a few blood losses, and no cases needed blood transfusion. Surgical margins of all cases were negative, and no cases underwent tumor recurrence. No cases had aggravations of renal functions, however two cases had complications which were perirenal urine leakages. Both cases were improved by only drainages.
In this study, it suggests that partial nephrectomy using microwave tissue coagulator is considered to be safe and useful.

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We compared efficacy, morbidity, and convalescence between laparoscopic and open nephron sparing surgery using a microwave tissue coagulator without renal pedicle clamping. Laparoscopic and open nephron sparing surgeries were performed for 11 and 5 patients, respectively, with small renal cell carcinoma from 1991 to 2002. Comparable results of laparoscopic nephron sparing surgery were obtained to open surgery regarding operation time, blood loss and postoperative renal function. However, two patients were converted to open surgery due to residual malignant cells, and each of them underwent subsequently open radical or partial nephrectomy. Another patient required open nephrectomy after laparoscopic nephron-sparing surgery due to the prolonged urine leakage and uncontrolled infection. Infundibular stenosis and calyectasis developed in a patient 3 months after open surgery. A microwave tissue coagulator was useful to control parenchymal bleeding without real pedicle clamping during laparoscopic and open nephron-sparing surgery. However, to prevent post-operative complications such as urine leakage and infundibular stenosis, it should be contraindicated in a case of renal cell carcinoma buried in parenchyma or near the calyx, sinus and large renal vessels.

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We report two cases who underwent partial nephrectomy using Micorotaze^® for a small renal tumor or a recurrent renal cell carcinoma after ipsilateral partial nephrectomy. This procedure is one of the options as a surgical treatment for small renal tumors. However, its indication should be carefully considered according to the size and the location of the tumors.

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We performed partial nephrectomy using a microwave tissue coagulator (MTC) for 7 patients with renal tumor between August 2001 and July 2003. Six renal cell carcinomas, 2 leiomyomas, and one angiomyolipoma were completely resected. Four patients underwent open partial nephrectomy via a retroperitoneal approach and 3 patients underwent retroperitoneoscopic partial nephrectomy. Except one case the blood loss during operation was small, especially in laparoscopic procedure. Other major complications were renal necrosis in a large renal angiomyolipoma (6 cm) and a large urinoma formation in another case. Recently for the purpose of decreasing of heat damage by microwave coagulation out put was decreased to 40 watt for 30 seconds and no bleeding was found during the resection.

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We report two patients who underwent laparoscopic partial nephrectomy using a microwave tissue coagulator who suffered relatively severe complications. One was a 63-year-old man whose serum creatinine level gradually increased postoperatively and in whom ipsilateral renal function was almost lost at 3 months postoperatively. We suspect that the microwave coagulator came into contact with the main renal artery and that blood supply to the affected kidney was stopped in this case. In another 46-year-old woman, prolonged leakage of urine was observed in the postoperative period, but resolved after 2 months. We speculated that the cause of this leakage was irreversible damage to collecting system tissue by the microwave coagulator. In conclusion, care is needed concerning the portion of tissue and depth of needle insertion in laparoscopic partial nephrectomy using a microwave tissue coagulator.

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The case is 70-year-old male who was treated with transurethral resection (TUR-Bt) and transurethral microwave coagulation therapy (TUMCT) for urinary bladder cancer (TCC, G2, pTaN0M0) on March 23, 2000. Eight months later, multiple vesical calculi with broad calcification of the bladder mucosa was diagnosed. Transurethral lithotripsy was performed on December 20. The constituents of the calculi were magnesium ammonium phosphate and calcium phosphate. Recurrent tumor was not observed in the bladder. However the cause of this calculi are unknown, there is a possibility that coagulated bladder tissue and urine made the calculi.

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