Transurethral microwave thermotherapy: first experiences in Poland

OBJECTIVE

To present early experiences in Poland with high-energy transurethral microwave thermotherapy (HeTUMT), considered as a serious alternative to surgery in managing benign prostatic hypertrophy (BPH).

PATIENTS AND METHODS

Sixty-one patients were treated in two centres using a commercial TUMT system. The patients were assessed at 5-6 weeks, 3 and 6 months after treatment, evaluating subjective complaints, the International Prostate Symptom Score (IPSS), urinary flow rate and postvoid residual volume.

RESULTS

A complete follow-up was available in 44 patients; most had symptomatic improvement 3 months after HeTUMT but it was slightly less pronounced after 6 months. The improvement in objective variables increased up to 6 months after HeTUMT. There was > or = 50% improvement in subjective complaints in 43% of the patients, in urinary flow rate in 25% and in residual urine in half. Two patients required re-treatment for a urethral stricture and ineffective HeTUMT.

CONCLUSIONS

HeTUMT may be a useful treatment for BPH but the outcome for an individual patient seems to be unpredictable. The indications for TUMT should be reviewed individually for each patient.

A patient with small-cell carcinoma of the stomach with long survival after percutaneous microwave coagulating therapy (PMCT) for liver metastasis

A 66-year-old man was admitted to our hospital with epigastralgia. Preoperative examinations revealed an 8.0 x 8.0-cm, Borrmann type 2 tumor in the posterior wall of the cardia, without distant metastases. Total gastrectomy with pancreato-splenectomy and regional lymph node dissection was performed curatively. Histologically, the tumor was composed mainly of small cells with hyperchromatic nuclei and scant cytoplasm, which showed positive staining for Grimelius, gamma-neuron-specific enolase (gamma-NSE), chromogranin A, and serotonin. About 10 months after the operation, a solitary tumor was revealed in S8 of the liver by abdominal computed tomography (CT), and it was histologically confirmed by needle biopsy to be a metastasis of the small-cell carcinoma from the stomach. Instead of hepatectomy, percutaneous microwave coagulating therapy (PMCT) was indicated, because of the patients' liver dysfunction (ICG R15, 39.9%); CT showed complete necrosis of the metastatic focus in the liver after the PMCT. Now, 33 months after the first detection of the liver metastasis (43 months after the gastrectomy), the patient is still alive without any growth of the liver metastasis. The 67 previously reported cases of small-cell carcinoma of the stomach in Japan, including ours, are also reviewed.

Baseline prostatic specific antigen does not predict the outcome of high energy transurethral microwave thermotherapy

PURPOSE

We assessed the prognostic value of baseline prostate specific antigen (PSA) for outcome after high energy transurethral thermotherapy in patients with lower urinary tract symptoms.

MATERIAL AND METHODS

Data were collected prospectively in 404 consecutive patients treated with high energy transurethral thermotherapy with the Prostatron device (EDAP-Technomed, Lyon, France). Patients were followed a minimum of 1 year. At baseline certain criteria were assessed, including pretreatment PSA, uroflowmetry, ultrasound measurement of prostatic volume, voided and post-void residual urine volume, and International Prostate Symptom Score (I-PSS) and quality of life scores. Outcome assessment included I-PSS, quality of life score and uroflowmetry of peak urine flow. Linear regression analyses were performed to correlate baseline PSA with improved clinical parameters at 12 months of followup. Logistic regression analyses and receiver operating characteristics curves characterized the ability of baseline PSA to discriminate patients with a more or less favorable outcome.

RESULTS

An evident linear association was identified for prostate size at baseline and PSA. After 1 year 36 patients were treated again due to transurethral thermotherapy failure and 16 had died, which was not related to lower urinary tract symptoms or treatment for lower urinary tract symptoms. To include re-treated patients in the analyses we considered that their I-PSS, quality of life and peak urine flow values at 1 year were unchanged compared with baseline. Of the 388 evaluable patients an improvement of 50% or more in I-PSS, quality of life and peak urine flow was observed in 57%, 62% and 44%, respectively. Absolute mean changes at 1 year were -9.7, -2 and 5.2 ml. per second for I-PSS, quality of life and peak urine flow, respectively. Neither linear nor logistic regression analysis showed any clinically relevant correlation between baseline PSA and changes in I-PSS (r = -0.004), quality of life (r = -0.135) or peak urine flow (r = 0.105) at 1 year. Receiver operating characteristics curves failed to distinguish more or less favorable outcomes in all evaluated parameters.

CONCLUSIONS

Pretreatment PSA cannot predict the clinical outcome after high energy transurethral thermotherapy.

[Effect of microwave coagulation and surgery to treat the cancer of the floor of mouth]

OBJECTIVE

The aim of this article was to clarify the value of microwave coagulation to treat the cancer of the floor of mouth by comparing the effect of microwave and surgery.

METHODS

Retrospectively 87 cases of cancer of the floor of mouth who were treated by microwave coagulation and traditional surgery are analysed and the survival curve, the recurrent rate of the primary and secondary site, the oral functions, the appearance and the complications are compared.

RESULTS

1. Either in the early patients (T1 + T2) or in the advanced cases (T3 + T4), the differences of survival curve between the two groups were insignificant (P = 0.8247, P = 0.803 respectively); 2. The recurrent rate of the primary and secondary site were insignificant either (P = 0.988, P = 0.759 respectively); 3. There were more patients with a satisfied mouth function in the microwave coagulation group than that of in the surgery group, on the contrary, the cases with a worst function were few in the former(P = 0.000, P = 0.001 respectively); 4. The appearance was more satisfactory in the microwave group(chi 2 = 23.077, P = 0.000).

CONCLUSIONS

To treat the cancer of the floor of mouth, microwave coagulation, as the traditional surgery, had good effects such as the same survival rate, the complication rate and local or region control rate, but the mouth function and the appearance was better than the surgery group. The microwave coagulation can be safely carried out in the practice.

[Influencing factors of local immunocyte infiltration in hepatocellular carcinoma tissues pre- and post-percutaneous microwave coagulation therapy]

OBJECTIVE

To investigate the influencing factors of the local immunity in tissues of hepatocellular carcinoma (HCC) before and after percutaneous microwave coagulation therapy (PMCT).

METHODS

Seventy-eight patients with HCC diagnosed by needle biopsy of liver underwent PMCT. Before the treatment and three and 17 days after the treatment specimens of carcinoma tissues were obtained by ultrasound-guided liver biopsy. The extents of infiltration of CD3(+) cell, natural killer cells (CD56(+)), and macrophages (CD68(+)), and the expression rate of proliferating cell nuclear antigen (PCNA) were evaluated by immunohistochemistry. The relation between the extents of immunocyte infiltration and the clinical parameters was analyzed with multiple regression.

RESULTS

Before PMCT infiltration of the three kinds of immunocytes was found in the carcinoma tissues to different degrees with a great variation among individuals. A remarkable increase in the extent of infiltration of the three kinds of immunocytes was found three days after the treatment and continued or remained till the 17th post-PMCT day (P < 0.01). The post-PMCT extent of immunocyte infiltration was positively correlated with the pre-PMCT extent (CD3(+): r = 0.256, P = 0.005; CD56(+): r = 0.257, P = 0.002; CD68(+): r = 0.275, P = 0.001). A negative correlation was found between the extent of immunocyte infiltration and serum alpha-fetal protein (AFP) and between the extent of immunocyte infiltration and tumor size (for serum AFP, CD3(+): r = -0.075, P = 0.049; CD56(+): r = -0.062, P = 0.041; CD68(+): r = -0.007, P = 0.035; for tumor size, CD3(+): r = -0.074, P = 0.051; CD56(+): r = -0.100, P = 0.012; CD68(+): r = -0.109, P = 0.038). No correlation was found between the extent of immunocyte infiltration and age of patient, Child-Pugh class of tumor, grade of tumor differentiation, and number of tumor. The extent of immunocyte infiltration was lesser in the carcinoma tissues with higher expression rate of PCNA. The extent of immunocyte infiltration was greater in the carcinoma tissues where PCNA expression was negative and carcinoma cells had necrotized but with their structure recognizable. No immunocyte infiltration was found in the necrotic and structureless tumor tissues.

CONCLUSION

The local immunocyte infiltration in patients with HCC was influenced by serum AFP and the grade of tumor cell necrosis pre- and post-PMCT. Destruction of tumor tissue in situs by PMCT is the premise of increase of immunocyte infiltration. Before PMCT improving the immune status of the patients helps enhance the local immune response.

Influence of hydrocortisone and microwave radiation on the mechanical characteristics of rat bone tissue

This work deals with the mutual action of hydrocortisone and low intensity microwave radiation (MWR) on the bone tissue of rats. The bone density and velocity of ultrasound was measured in order to evaluate the Young's modulus of the femur. The results show a stimulating effect of the low-intensity MWR field on regeneration of the bone tissue of rats. The MWR, during a long application of hydrocortisone, may be a characteristic protective factor for the bone tissue.

Nonsurgical treatment of hepatocellular carcinoma: from percutaneous ethanol injection therapy and percutaneous microwave coagulation therapy to radiofrequency ablation

Treatment of hepatocellular carcinoma (HCC) is different from that of other solid tumors, in that surgery plays a limited role while nonsurgical therapies are very instrumental. At our institute, 90% of previously untreated patients have received image-guided percutaneous tumor ablations, such as percutaneous ethanol injection therapy (PEIT), percutaneous microwave coagulation therapy (PMCT) and radiofrequency ablation (RFA). We performed PEIT in 756 patients with HCC. Their survival rates were 89% at 1 year, 64% at 3 years, 39% at 5 years, and 18% at 10 years. With PMCT, survival rates of 122 new patients with HCC were 90% at 1 year, 87% at 2 years, and 68% at 3 years. We performed RFA in 324 patients. RFA required fewer treatment sessions and a shorter hospital stay than PEIT or PMCT to achieve complete necrosis of the lesions. By virtue of their local curability, minimal effect on liver function, and easy repeatability for recurrence, image-guided percutaneous tumor ablations, especially RFA, will be increasingly important in the treatment of HCC.

Non-ischemic nephron-sparing surgery for small renal cell carcinoma: complete tumor enucleation using a microwave tissue coagulator

OBJECTIVE

To determine the methodological usefulness of non-ischemic complete enucleation for small renal cell carcinomas (RCC) using a microwave tissue coagulator (MTC).

METHODS

Fifty-nine patients (61 kidneys) underwent non-ischemic complete tumor enucleation by MTC. Of the 59 patients, 46 had an elective indication and 15 kidneys of 13 patients had an imperative indication. RCC was exposed with minimal peri-renal detachment. The demarcation line, 7-10 mm from the tumor, was coagulated at 8-10 mm intervals with a microwave antenna needle for 30-40 s at 50-60 W. The renal tumor was excised along the coagulated zone with normal surrounding tissue. The enucleation bed was covered with fibrin glue or fat tissue without approximation.

RESULTS

The operations were successfully completed in all intended cases. The mean operation time was 160 +/- 43 (median: 160) min and the mean blood loss was 313 +/- 370 (median: 158) ml. No major bleeding or urine leakage from the enucleation bed was observed in 62.2 and 88.5% of cases, respectively. The minor bleeding and urine leakage were controlled easily with absorbable sutures. None of the cases presented with postoperative bleeding or urine leakage from the enucleation bed. Severe impairment of the renal function was not observed in any case evaluated by means of serum creatinine, creatinine clearance and radioisotope examination. The 5-year overall survival rate was 87% without recurrence up to 23.1 +/- 19.5 months of the mean follow-up.

CONCLUSION

Non-ischemic complete tumor enucleation using MTC constitutes a simple, reliable and less invasive alternative to ordinary nephron-sparing surgeries for small RCC.

Mediating transurethral microwave thermotherapy by intraprostatic and periprostatic injections of mepivacaine epinephrine: effects on treatment time, energy consumption, and patient comfort

BACKGROUND AND PURPOSE

Profound intraprostatic blood flow may complicate reaching a therapeutic temperature in the prostate during transurethral microwave thermotherapy (TUMT) for benign prostatic hyperplasia (BPH). A retrospective survey is presented describing the effect of intraprostatic and periprostatic administration of mepivacaine epinephrine on treatment time, intraprostatic blood flow, energy delivery, and patient comfort.

PATIENTS AND METHODS

Fifteen consecutive obstructed patients with lower urinary tract symptoms attributable to BPH received TUMT (ProstaLund Feedback Treatment). In order to improve patient comfort, injections of 10 mL of 0.5% mepivacaine epinephrine were administered in three locations into the prostate prior to treatment. The results were compared with those of a reference group consisting of 35 consecutive patients who had received ProstaLund Feedback Treatment without administration of mepivacaine epinephrine.

RESULTS

Patients who received intraprostatic mepivacaine epinephrine had a shorter treatment time (32+/-9 minutes v 61+/-6 minutes), required less energy (65+/-27 kJ v 172+/-32 kJ), and had a lower calculated intraprostatic blood flow (13+/-5 units/minute v 26+/-12 units/minute) than the reference group. Patients receiving mepivacaine epinephrine also required less analgesic medication during the treatment. The clinical outcome in terms of symptom scores and peak uroflow rates appeared to be similar for the two groups.

CONCLUSION

Intraprostatic injection of mepivacaine epinephrine prior to TUMT seems to have beneficial effects. It may represent an important improvement of thermotherapy and enable successful treatment of those patients who previously failed secondary to a profound intraprostatic blood flow.

Microwave endometrial ablation: patients' experiences in the first 3 months following treatment

The aim of this study was to investigate patients' experiences in the first 3 months following microwave endometrial ablation (MEA) for menorrhagia as well as the suitability of local anaesthesia (LA) versus general anaesthesia (GA) for these procedures. We carried out a cross-sectional questionnaire survey of 173 patients at 3 months after treatment with MEA. All were treated between September 1997 and December 1999. The setting was a small free-standing hospital day unit equipped with a minor operating theatre. Interventions were pretreatment with danazol or goserelin, followed by endometrial ablation with microwaves under GA or LA. Of the 173 patients, 98 (57%) were treated under GA, and 75(43%) under LA. The return of questionnaires was high in both groups (90% for GA and 84% for LA) and all procedures were completed with the planned anaesthetic. Commonly reported symptoms were immediate postoperative pain (61%), abdominal pain in the following weeks (75%), vaginal discharge (87%), vaginal bleeding (74%) and vaginal dryness. Reported symptoms were usually mild and not requiring medical intervention, e.g. in 124 patients (71%), postoperative pain was either absent or mild with no analgesics required. Only 4% had severe pain requiring a single dose of opiate analgesia. The results were similar in both groups. Sixty-nine per cent (104 patients) had no pain 1 week after treatment. This increased to over 90% by the end of the third week. Results were similar in those treated under LA (83% and 96%, respectively). There was early return to normal daily activity (70% by 1 week and 95% by 3 weeks). Reported symptoms were usually mild and not severe enough to warrant consultation of their doctor or the hospital. There were no blood transfusions or hysterectomy within the first 3 months of treatment. We conclude that MEA is well tolerated by patients. Reported side effects are usually minor. LA is comparable to GA and seems to have potential benefits.

[Research on the hyperthermia-therapy performances of invasive microwave antennas]

The paper introduces four kinds of 2450 MHz antennas including noninsulted (bare), insulated-open-tip (I.O.T.), dipole-type and sleeve invasive microwave ones. The comparison between the antennas' hyperthermia performances in the muscle tissue phantom made by specific absorption rate (SAR) shows that the sleeve antenna is the best. It has a bigger heating range and a changeless shape and is independent of the inserting depth.

Long-term effects of transurethral microwave thermotherapy

BACKGROUND

To identify the clinical valuables predicting a favorable outcome after transurethral microwave thermotherapy (TUMT) of the prostate with Prostatron.

METHODS

One hundred and two patients with lower urinary symptoms were treated with TUMT using a Prostatron device with the low-energy protocol (Prostasoft version 2.0 J). The pre-operative subjective score and objective voiding parameters were collected from the medical record. To test the differences in the risk of the necessity for additional treatments for several subgroups, Kaplan-Meier survival analyses and log-rank tests were used.

RESULTS

The Kaplan-Meier analyses showed that 67% of the patients received additional treatment within five years. The median period for receiving additional treatment was 37 months. The patients with a peak flow rate greater than 6.5 mL per second, with a urethral length less than 40 mm, or with an age over 64 years all demonstrated a significantly longer period before receiving additional treatment, when compared with their counterparts. These three factors were also significant in multivariate analysis to predict the long-term outcome.

CONCLUSIONS

Overall durability of TUMT was limited. Aged patients with a relatively high peak flow rate or with a short prostatic urethral length resulted in lower risk of receiving additional treatments after TUMT.

Alternative techniques for the treatment of colon carcinoma metastases in the liver: current status in The Netherlands

BACKGROUND

Review of current treatment modalities for liver metastases resulting from colorectal cancer.

METHODS

Literature review.

RESULTS

An increasing number of techniques are available for the treatment of colorectal liver metastases. When it is not possible to use the current gold standard, radical surgical resection, many patients can be treated with alternative techniques. Chemotherapy in its present form must be considered as purely palliative, perhaps with the exclusion of isolated liver perfusion: however, this therapy should still be considered as experimental. Most other possible treatments focus on local destruction of the metastases. This can be achieved using either immuno-guided techniques (tumor antibodies which carry a local active agent), direct local application of a toxic agent (injection) or thermo therapy, which has been applied in patients on a large scale. Thermo therapy involves either localized heating, by means or laser photocoagulation or radiofrequency or microwave ablation, or localized freezing using cryo probes.

CONCLUSIONS

Local destruction of liver metastases, especially by means of thermo therapy, is feasible and safe. Currently, cryotherapy is most frequently used in patients. New treatment modalities, such as radiofrequency ablation, arc very promising but their true clinical value should be determined in a randomized clinical trial.

Rationale and assessment of minimally invasive approaches to benign prostatic hyperplasia therapy

Benign prostatic hyperplasia affects quality of life, with most patients complaining of symptoms related to urination. For this reason, successful treatments can be defined by (1) their effect on lower urinary tract symptoms, (2) their impact on quality of life, and (3) their ability to unobstruct the flow of urine through the prostate. Minimally invasive therapy (MIT), which includes transurethral microwave thermotherapy, water-induced thermotherapy, interstitial devices (eg, transurethral needle ablation), and interstitial laser treatments, offers physicians and their patients cost-effective alternatives for achieving a substantially improved quality of life at an acceptable level of risk. Evidence-based medicine indicates that MIT is safe and achieves significant symptomatic improvement. Compared with long-term medical management, minimally invasive procedures offer effective, well-tolerated 1-time intervention with lasting effects that can be achieved on an outpatient basis. This article reviews the options for MIT.

Post-treatment malignant liver lesions. MR imaging

MR imaging is very accurate in the diagnosis and staging of tumors and in surgical planning. MR imaging is also an excellent method for evaluation of the liver after surgical resection, systemic or local tumor therapies, and liver transplantation. It permits early recognition of complications and the presence of recurrent tumor, providing an opportunity to repeat treatment or use alternative treatment. Surgical resection remains the standard therapy for treating liver metastases. The relatively small number of patients who are candidates for curative resection have provided impetus for the implementation and improvement of other techniques. The variety of techniques and the sensitivity for contrast enhancement have made MR imaging an ideal method to follow the response of tumors to various treatment approaches. The appearance of tumor recurrence and the response to treatment are relatively consistently shown on MR images; however, the time course of change in lesion appearance has not been fully elucidated, particularly in the setting of chemotherapy. Evaluating the response to chemotherapy is rendered complex because of the longer duration of the therapy, the types of response that various chemotherapeutic agents engender, the method of action of this therapy and the time of imaging in relation to therapy. The various local therapies share some general principles of action, and many have similar MR imaging findings. Some local therapies are effective only with certain malignancies (e.g., alcohol therapy and HCC), whereas other therapies are more limited because of the size of the tumor kill zone (e.g., interstitial laser therapy). We are in the early stages of using MR imaging to guide local therapies and to monitor response during treatment in real time. This appears to be an important future direction for MR imaging. The role of MR imaging in liver transplantation involves pre- and postoperative investigation of both donors (in the case of living-related transplantation) and recipients. These issues are described further in the section on MR imaging of liver transplantation.

Percutaneous microwave tumor coagulation for hepatocellular carcinomas with interruption of segmental hepatic blood flow

PURPOSE

To assess the effect of hepatic artery occlusion with or without hepatic venous outflow interruption on coagulation diameter during percutaneous microwave coagulation therapy (PMCT) for hepatocellular carcinoma (HCC) by a prospective and randomized trial.

MATERIALS AND METHODS

Thirty-one patients with 36 HCCs (10-38 mm in diameter) were randomly separated into two treatment groups as follows: group 1 (14 tumors in 14 patients) was treated with PMCT in conjunction with both segmental hepatic artery embolization with gelatin sponge particles and temporary interruption of hepatic venous flow by means of a 6-F balloon catheter to reduce the portal venous flow; group 2 (22 tumors in 17 patients) was treated with PMCT with segmental hepatic artery embolization only. PMCT under ultrasound (US) guidance was performed with 2,450 MHz of microwave frequency at 40-60 W and a needle applicator 1.6 mm in diameter. The coagulated area was measured at the maximum diameter perpendicular to the needle tract on enhanced computed tomography (CT) performed immediately after PMCT. The local effect of the treatment was evaluated by follow-up enhanced CT (6-33 mo).

RESULTS

Patients in group 1 had a significantly larger coagulation area (mean +/-SD = 42.9 mm +/- 8.3), with coagulation times of 5.3 min +/- 1.4, than patients in group 2 (32.6 mm +/- 8.0), with coagulation times of 4.2 min +/- 1.3 (P <.05). Follow-up enhanced CT showed no local enhancement of the tumor, indicating complete necrosis and no local recurrence, except for four tumors. There were no major complications after PMCT except liver abscess that developed after PMCT in one patient with pneumobilia.

CONCLUSIONS

PMCT with combined hepatic arterial embolization and temporary hepatic venous flow interruption can coagulate significantly larger volumes of tumor than PMCT with only hepatic arterial embolization.

A case of hepatocellular carcinoma rupturing after angiography

We report a case of primary hepatocellular carcinoma (referred to as hepatocellular carcinoma below) apparently rupturing after angiography. The patient was a 62-year-old male who was admitted for the treatment of hepatocellular carcinoma. Ultrasonography (US) and computed tomography (CT) on admission showed a tumor occupying the entire left lobe of the liver and partly protruding outside the liver and a tumor embolus in the portal vein. We performed preoperative angiography, after which fever and abdominal discomfort appeared. Two days after the angiography, abdominal pain and a rapid increase in the size of the abdominal tumor were noted. US also revealed an unquestionable increase in the size of the tumor, leading to a diagnosis of intratumoral hemorrhage due to the rupture of hepatocellular carcinoma. Since child classification A, clinical stage I and ICG 11.7% indicated an adequate functional reserve of the liver, we performed an emergency operation. Laparotomy revealed that the tumor occupied almost the entire left lobe of the liver, partly protruded outside it, and was bleeding from part of its anterior surface. The volume of intra-abdominal hemorrhage was about 100 ml. A portal tumor embolus was present in the portal vein from the horizontal part to the trunk. We performed resection of the left and caudate lobes of the liver with removal of the portal tumor embolus. The resected specimens showed a hemorrhage in and around the tumor. We speculated that in a hepatocellular carcinoma that involves the surface of the liver and is complicated by tumor embolism of the portal vein, angiography could trigger the rupture of the carcinoma.

[Study of a new microwave applicator for hyperthermia treatment of uterocervical cancer]

A new microwave applicator for intracavitary hyperthermia treatment of uterocervical cancer has been designed and tested. Compared with the traditional microwave applicators, the exposed inner conductor of this applicator is replaced by a cone-helical antenna with the reflect shade. We confirm that the heat pattern of the applicator is shifted towards the tip in muscle tissue equivalent phantom material. The result indicates that this new applicator may play an important role in clinical use for treatment.

Morphological and biological predictors for treatment outcome of transurethral microwave thermotherapy

The proliferation of prostatic tissue as a result of ageing typically leads to prostatic enlargement, which often causes obstruction of urine outflow from the bladder, clinically lower urinary tract symptoms, detrusor instability, incomplete bladder emptying, urinary infection, and finally acute urinary retention. The first approach to therapy depending on the severity of the symptoms is usually medical management (phytotherapy, alpha-blockers, 5 alpha-reductase inhibitors) before surgical procedures are performed. The reference standard for treatment of benign prostatic hyperplasia is transurethral resection of the prostate, although the introduction of minimally invasive alternatives such as transurethral microwave thermotherapy has led to a new era in surgical management. Suitable patients must be selected carefully on the basis of individual parameters that predict a favourable result.

[Curative effect of percutaneous microwave coagulation therapy for hepatocellular carcinoma]

OBJECTIVE

To observe the curative effect of percutaneous microwave coagulation therapy (PMCT) with 2450 MHz microwave antenna for hepatocellular carcinoma.

METHODS

Under local or epidural anesthesia, a thin percutaneous microwave antenna was introduced with ultrasound guidance into the tumor in the liver for thermo-coagulation.

RESULTS

Among the 97 hepatic cancer lesions in 52 patients, 61(62.9%) with phi < 3 cm were coagulated once. In follow-up of 6-12 months of these lesions, 57(93.4%) showed no recurrence by CT or MRI. Thirty-six (37.1%) with 3 cm < phi < 5 cm coagulated twice showed that 27 (75.0%) gave CR and 9 (25.0%) gave PR by CT or MRI in follow up of 6 months. There were no serious clinical side effects or complications in the PMCT patients.

CONCLUSION

Percutaneous microwave coagulation therapy gives good curative effect on liver tumor with phi < 3 cm. It is partly effective on lesions 3 cm < phi < 5 cm.

[A long-term survivor undergoing microwave coagulation therapy for hepatocellular carcinoma located just above the main trunk of right hepatic vein]

A 52-year-old male had hepatocellular carcinoma (HCC), located just above the main trunk of the right hepatic vein. Firstly, this patient was treated by TAE. However, the effect was incomplete, so the patient was referred to Kurashiki Medical Center for additional therapy. Microwave coagulation therapy (MCT) under laparotomy was performed due to the deterioration of hepatic functional reserve. The level of AFP decreased to the normal range. Recurrent HCC was found at medial segment of the liver by MRI taken seven months after the first MCT. MCT was performed again intraoperatively. The main trunk of the right hepatic vein was proved to be patent by enhanced CT. Furthermore, this patient has lived without tumor recurrence for 34 months after the second MCT. This case shows that MCT is a useful method to treat HCC located near the main hepatic vein.