We started radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) in 2000. We reported cytological evidence of amorphous or linear aggregating necrosis in HCC after RFA. Interactive algorithm can enhance necrosis than standard algorithm when using LeVeen electrode. RFA was superior to ethanol or acetic acid injection in terms of lower local recurrence and higher overall survival rate for HCC ≤ 3 cm or 4 cm. Equivalent complete necrosis and local tumor progression were found across the current 4 RF devices for HCC of ≤ 4 cm. When using internally cooled electrode, manually pulsed RF algorithm was equivalent to automatically pulsed RF algorithm regarding complete necrosis and local tumor progression but automated algorithm was less cumbersome. In HCC with high-risk location, combined ethanol injection and RFA had a trend of higher complete necrosis than RFA monotherapy, and comparable rate of complete necrosis compared with HCC in non-high-risk locations undergoing RFA monotherapy.

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Radiofrequency (RF) ablation was recently introduced as a novel ablation modality for hepatocellular carcinoma (HCC). Several investigators have reported that percutaneous RF ablation for patients with small HCC nodules provide favorable survival with excellent local control. However, several limitations of RFA have been pointed out, such as limited coagulated necrosis and relatively frequent local recurrences in large HCC. The critical factors for treatment success in large tumors included (a) the target diameter of an ablation- or of overlapping ablations - must be larger than the diameter of the tumor that undergoes treatment; (b) reduce the negative effect of blood flow and tissue perfusion on RF heating. To overcome RF limitations, researchers developed several techniques and skills of percutaneous treatments and several studies have demonstrated that multiple RF ablation processes with overlapping of ablation zones or combination therapies are feasible for large liver tumors. In this review, we analyzed varies of treatment strategies for percutaneous RF of large tumors and summarized the efficacy of clinical application.

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Treatment results for HCC were the barrel severely one, 30 years ago. At that time, the liver resection was not safe maneuver yet, though there was no effective treatment method except the liver resection. Afterwards, the liver resection has rapidly evolved to the safe cure by the establishment of hemostasis such as microwave coagulation during resection and the development of the operation equipment.
Hepatic resection and other treatment for HCC have showed remarkable progress in these 2 decades. This progress brought dramatic improvement of curability for HCC.
In addition, advancement of diagnostic imaging, development of tumor maker of HCC resulting in definition of high risk group of HCC, led to the further improvement of treatment result of HCC.

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The underlying hepatopath may cause intra-hepatic recurrence even if curative resection for hepatocellular carcinoma (HCC) is achieved. Two patterns of intra-hepatic recurrence is exist, multicentric carcinogenesis with chronic hepatopath and intra-hepatic metastasis. We must diagnose the difference of these 2 characters after treatment, hepatectomy or ablation, for HCC and perform the post-operative adjuvant therapy expecting the 2 patterns. The prevention of multicentric carcinogenesis is postoperative interferon (IFN) therapy on hepatitis C virus-related HCC and the prevention of intrahepatic metastasis is postoperateive transcatheter arterial infusion chemotherapy (TAI) and cell immunotherapy on advanced HCC. The postoperative adjuvant therapy for HCC was found to be an effective adjuvant therapy that significantly improved survival and disease-free survival rates, and we have been not satisfied with the therapiatic effects. Although randomized controlled study with a greater number of patients is necessary.

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In recent years endoscopic surgery has spread worldwide and has been performed widely in the field of liver surgery. Endoscopic surgery for hepatocellular carcinoma (HCC) was adopted in our department in 1994. On the other hand, local ablation therapy has also become established as one of the effective therapies for HCC. However, there is a limit for percutaneous ablation, and overdoing can cause. Endoscopic ablation is used to relieve this condition. Indication for ablation therapy has spread through the increasingly precise use of thoracoscopes and laparoscopes. Furthermore, further ingenuities of endoscopic technique will widen the range of indication as well as improve safety and certainty of ablation therapy.
We encourage a wider application of ablation therapy for use as a treatment strategy for HCC.

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We previously reported that radiofrequency (RF) ablation combined with transcatheter arterial embolization (TAE) using iodized oil and gelatin sponge created wedge-shaped necrotic area starting from the ablation zone to the periphery of the liver in animal model. In this study, we evaluated the extended effects of the combination therapy to 17 patients with hepatocellular carcinoma (HCC) located periphery of the liver. Immediately after segmental TAE, RF expandable electrode was inserted to proximal portion of HCC. In 16 of 17 patients, wedge-shaped segmental necrotic area including HCC was confirmed by CT, and no local tumor recurrences were observed during 24-48 months of follow-up periods. Three adverse events (pleural effusion) were related to the treatment. We conclude that this combination therapy makes it possible to induce the wedge-shaped segmental necrosis including HCC.

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We examined whether live 3D imaging on ultrasonography (US) is valuable to display the accurate position of percutaneous radiofrequency ablation (RFA) needle in the nodule of hepatocellular carcinoma (HCC).
It was possible to obtain accurate position of the needle during RFA procedure in all 18 nodules. The needle was confirmed to be inserted into the center of the tumor nodule by various angles. It appeared that live 3D US provides more perceptible information on the spatial relationship between RFA needle and the target lesion.

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We examined the characteristics of hepatocellular carcinoma patients with 10-year survival who had received initial treatment and been followed up for more than 10 years at our hospital. The 10-year survival rate was 12%, and comparison of patients who survived for 10 years (n = 36) and those who did not (n = 265) showed that the former had better hepatic functional reserve, with mild tumor progression and rates of usage of post-treatment interferon therapy and performance of hepatectomy. Comparison of patients with hepatectomy (n = 24) and those with percutaneous ablation therapy (n = 10) who survived for 10 years showed that those with hepatectomy had lower total bilirubin values, higher platelet counts, and larger tumor diameters. The total number of treatments in patients with tumor recurrence who survived for 10 years was 9.6 ± 5.2 in the case of hepatectomy and 14.6 ± 8.0 in the case of percutaneous ablation therapy. These findings suggest that repeated treatment can lead to long-term survival in patients with good hepatic functional reserve in whom initial treatment is radical and in whom subsequent periodic follow-up yields early detection of tumor recurrences.

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We aimed to clarify the appropriate indication of the ablation therapy for hepatocellular carcinoma (HCC). Seventy-five patients treated for HCC in our department were divided into ablation group (ABL, n=10) and hepatectomy Group (n=65) by the initial treatment. Overall survival, disease free survival, and recurrence rate were compared. We also examined the therapeutic results for recurrent HCC (n=39). Treatment procedure, detail of the ABR recurrence patients (n=9) and survival were examined.
There was no difference on survival. Recurrence rate was higher in ABL group. Of the recurrent patients in ABL group, 3 local recurrence patients received hepatectomy, and after that, re-recurrence did not occurred. Local control therapy was effective especially for multicentric carcinogenesis recurrent cases.
In conclusion, ablation therapy is one of the good modality for HCC. But for high recurrence rate, the treatment strategy should be prudent.

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Purpose: To evaluate the prognostic impact of microwave coagulo-necrotic therapy (MCN) versus hepatic resection (HR) on patient survival after treatment for hepatocellular carcinoma (HCC).
Materials & methods: Between July 1994 and December 2006, 1567 patients underwent hepatic surgery at our institute. Of these, 613 who received their initial therapy for HCC were analyzed. MCN was performed in 456 patients, hepatic resection (HR) in 111, and HR + MCN in 42. The remaining 4 patients were treated with laparotomic ethanol injection. We analyzed the therapeutic survival, local tumor progression and overall recurrence rates.
Results: The cumulative survival rates for patients treated with MCN (mean tumor size, 28.2 mm; mean number of lesions, 2.62) were 97.5, 77.6, 58.7, and 37.3%, at 1, 3, 5 and 10 years, respectively. The 5-year survival rate was 58.7% after MCN and 56.4% after HR (p = 0.9480).
The cumulative survival rates for 238 patients treated with MCN who had 3 or fewer lesions of ≤3 cm in diameter were 98.1, 85.2, 70.3 and 43.5% at 1, 3, 5 and 10 years,. There were no significant differences in cumulative survival (p = 0.7358), disease-free survival or local recurrence rates between patients treated with MCN versus those treated with HR. Of the 613 patients receiving their initial treatment, 319 had recurrences after an average of 639.6 days after operation; 61 of these had 4 or more recurrent lesions, while 204 patients could be treated with MCN (mean tumor size, 23.7 mm; mean number of lesions, 3.08).
Conclusion: Our findings suggest that MCN is an effective treatment for loco-regional control of HCC and is comparable to HR. MCN is particularly suitable for the treatment of patients presenting with multiple tumors or tumor recurrence. We recommend that HR and MCN should both be considered as first-choice treatments for HCC.

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We investigated efficacy of microwave ablation plus hepatectomy for multiple colorectal liver metastases. Clinicopathologic data were analyzed retrospectively for 97 consecutive patients with 4 or more bilobar liver metastases from colorectal cancer who underwent hepatectomy with or without microwave ablation. No significant differences were found for overall and disease-free survival between 26 patients with resection/ablation and 71 patients with resection (p = 0.68 and 0.60). Local liver recurrence occurred in 1 patient with combined resection/ablation, but no significant difference of liver recurrence pattern was observed between groups. In patients with combined resection/ablation, survival was significantly greater in prehepatectomy chemo-responders associating with less frequent microscopic cancer deposits surrounding liver metastases than in nonresponders. Microwave ablation plus hepatic resection expanded indications for surgery to treat multiple bilobar liver metastases without loss of survival efficacy, especially in prehepatectomy chemo-responders.

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Purpose: To evaluate the effectiveness of RFA for liver metastasis of colorectal cancer.
Methods: We performed RFA in 442 patients from April 2006 to June 2008 at Kanto Medical Center NTT EC. It contained 88 (the total number) of liver metastasis of colorectal cancer.
Results: We performed RFA in 47 patients (the actual number). The median age was 63 years-old (38-85) and 72.3% were male. The median tumor numbers were 5.5 (1-29) and median tumor size was 32mm (9-156). Thirty-four patients were performed chemotherapy before ablation. Three patients (3.4%) had complications; Liver abscess, hemoperitoneum and Liver failure. One year survival rate from the initial ablation was 80% and 2-year was 71%.
Conclusion: We think performing RFA to liver metastasis which were unable to be resected or be continued chemotherapy might improve the prognosis.

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There is a paucity of intrahepatic bile duct in the lateral segment of the liver, and the medial segment branches more than the umbilical portion of portal vein in the right, back, and left side. As well, as there are many anomalies, it is critical to perform RFA and MCN to ascertain biliary tract variations for a hepatocellular carcinoma (HCC) in the medial segment. Understanding any such variations before treatment can prevent problems.

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Background: During RFA, microbubbles can be observed by ultrasound. Microbubbles are thought to represent steam generated by rapidly heated tissue. Therefore, we used an angioscope to observe the microbubbles.
Subjects and Methods: Laparotomy was performed on 5 pigs. A 16-Fr sheath was inserted into the jugular vein. After inserting a 3.8-mm angioscope into the sheath, a guidewire was used to guide the angioscope to the hepatic vein, and RFA was performed. Microbubbles in the portal vein were also observed by angioscope. A LeVeen^TM needle electrode and a cooltip needle electrode were used for RFA.
Results: The outflow of microbubbles from the RFA site was observed by angioscope.
Conclusions: The results demonstrate that increased intrahepatic pressure causes microbubbles, thus suggesting that some risk of dissemination due to RFA exists.

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Endoscopic sphincterotomy (ES) is a popular technique for the management of common bile duct stones. However, bleeding is one of the most common and potentially serious complications of ES. In the present article we described 2 patients with ES-induced bleeding, in whom our endoscopic hemostatic technique of microwave tissue coagulation (MTC) arrested the bleeding. MTC is tissue coagulation leveraging auto-induction heat. Therefore, duodenal tissue is coagulated homogenously without carbonization and the coagulation area is limited within an area of 5 mm in width and 2 mm in depth at a coagulation under our operational conditions (50 watts times 3-5 seconds at one go) using coaxial cable of 2.4 mm in diameter. It means that by applying MTC hemostatic therapy for ES-induced bleeding, there is little risk of acute pancreatitis and duodenal perforation. Moreover, MTC therapy is able to approach from tangential adjusting easily with the straight-view scope. As a result, MTC therapy has an important advantage in terms of both facility and safety as an endoscopic hemostatic method for the treatment of ES-induced bleeding.

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Bile duct carcinoma is one of the most lethal and aggressive malignancies, with the majority of patients harboring unresectable tumors at presentation. The currernt conventional treatment for bile duct carcinoma is either bile duct resection with hepatectomy or pancreatoduodenectomy based on its location, according to the guidelines for diagnosis and treatment of bile duct carcinoma However, hepatectomy and/or PD is a major operation not well tolerated by jaundiced and aged patients in poor general condition with bile duct carcinoma.
We previously reported an inoperable jaundiced woman with bile duct carcinoma who underwent cholangioscopic MTC and survived longer than 13 years.
Here, we report another jaundiced patient with bile duct carcinoma with survival longer than 15 years after cholangioscopic MTC.
Our method (MTC) uses not only coagulation but also mild hyperthermia on the tumor margins as well as on the ductal lumen. Effects other than hyperthermia such as those of microwave dynamic therapy are also currerntly under investigation.
For some patients with bile duct carcinoma in poor general condition, with severe jaundice, and probable early stage of progression, cholangioscopic and X-ray image-guided MTC may be an alternative means of non-operative management aiming not only at palliation but also cure.
Which treatment should be chosen (surgical or non-surgical) for treatment in aged patients with bile duct carcinoma whose general condition is poor remains an unresolved issue.

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We have performed transurethral microwave tissue coagulation (MTC) for urinary bladder cancer. Previously, we applied this treatment to small recurrent tumors of outpatients under epidural anesthesia. In this report, we performed MTC for smaller tumors without anesthesia. Eight tumors from 2 mm to 5 mm in diameter, were treated. Six tumors were G1, and 2 tumors were G2. Coagulation time was 5 or 10 seconds, and coagulation was performed once or repeated 2 to 4 times. Five-second coagulation could be performed without pain, but 10-second coagulation caused controllable pain. In 2 cases, recurrent tumors were detected 4 and 6 months later, and this method was performed again. It is supposed that we could easily treat recurrent bladder cancer without anesthesia, which was smaller than 3 mm in diameter.

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Background: Microwave endometrial ablation is a new, minimally invasive treatment option for menorrhagia. Its popularity in many countries is increasing due to its safety and simplicity.
Cases: We treated menorrhagia due to submucosal myomas in patient with a modified microwave endometrial ablation device. Conventional surgery (total abdominal hysterectomy) was contraindicated in this patient because of acute hemorrhagic shock. In this case, microwave endometrial ablation was highly effective and patient was satisfied with her treatment outcome.
Conclusion: Given its safety, simplicity, and effectiveness, microwave endometrial ablation may be widely adopted for the emergent control of uterine bleeding in patients with acute hemorrhagic shock.

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