Treatment outcomes of endoscopic resection for rectal carcinoid tumors: an analysis of the resectability and long-term results from 46 consecutive cases.

AIM: In Japan, most of colorectal carcinoid tumors developed in rectum. The choice of treatment is important because surgical treatment may need to construct artificial anus. Although curative endoscopic resection (ER) is desirable from the point of quality of life, sufficient evidence of endoscopic treatment for rectal carcinoid tumors is not fully obtained. METHODS: Between April 2001 and August 2013, 46 rectal carcinoid tumors in 46 patients who underwent either with endoscopic mucosal resection with a ligation device (EMR-L) or endoscopic submucosal dissection (ESD) were analyzed retrospectively. The rates of en bloc resection, positive for lateral and/or vertical margin, curative resection, local recurrence, additional treatments, overall and disease-specific survival rate after ER were evaluated during follow-up (median observation period 61.6 months). RESULTS: Twenty-two lesions were treated by EMR-L and 24 lesions were treated by ESD. Both groups had similar mean tumor size (EMR-L: 6.2 mm, ESD: 6.0 mm). The rate of en bloc resection, negative for both lateral and vertical margins, and curative resection were, respectively, 73%, 63%, and 50% for EMR-L, 100%, 100%, and 83% for ESD. These results suggested that the rate of resectability and curability for ESD was significantly higher than EMR-L (p < 0.05). Complications such as perforation and bleeding did not occur in both groups. Fifteen patients were judged as non-curative and 3 patients underwent additional surgery and lymph node metastasis was evident in 1 patient. Remained 11 patients were carefully followed-up, and so far no obvious recurrence was found. Thirty-two patients (84%) were eligible for long-term follow-up and 5-year overall and disease-specific survival rates were 100% and 100%, respectively. CONCLUSION: The long-term outcomes of ER for rectal carcinoid tumors were excellent. ESD has advantage for resectability and curability compared with EMR-L; therefore, ESD is more favorable procedure as treatment for rectal carcinoid tumors.

Antithrombotic drugs are risk factors for delayed postoperative bleeding after endoscopic submucosal dissection for gastric neoplasms.

BACKGROUND: The discontinuation of antithrombotic drugs is recommended during endoscopic submucosal dissection (ESD) for gastric neoplasms; however, controversy remains as to whether antithrombotic drugs are risk factors for postoperative bleeding. OBJECTIVE: To determine the risk factors for post-ESD bleeding. DESIGN: Single-institution, retrospective review. SETTING: University hospital. PATIENTS: From June 2000 to December 2010, we treated 1192 gastric neoplasms in 1032 consecutive patients. INTERVENTION: The ESD procedures were performed by using the standard techniques. Antithrombotic drug therapy was principally interrupted preoperatively and was restarted when hemostasis was confirmed by second-look endoscopy. MAIN OUTCOME MEASUREMENTS: Risk factors for postoperative bleeding after ESD (early, delayed, and overall [combined] occurrence of bleeding during the first 5 postoperative days or thereafter) were analyzed by using logistic regression analysis. RESULTS: Among 1166 ESD-induced ulcer lesions, overall postoperative bleeding was evident in 62 lesions (5.3%); early and delayed bleeding occurred in 30 and 32 lesions (2.6% and 2.7%), respectively. Based on a multivariate analysis, a specimen size of >40 mm was the sole independent risk factor for overall bleeding. Moreover, oral antithrombotic drug therapy was selected as independent risk factor for delayed but not early bleeding, according to the multivariate analysis. The delayed bleeding rate in patients who had a specimen size of >40 mm and who used antithrombotic drugs was 11.6%. LIMITATIONS: Retrospective design and single-site data collection. CONCLUSION: Interruption of antithrombotic drug therapy may be adequate for preventing early post-ESD bleeding; however, reinitiating antithrombotic drug therapy is a significant independent risk factor for delayed post-ESD bleeding.

Adenocarcinoma arising from short-segment Barrett's esophagus in a young man.

We report herein a case of adenocarcinoma arising from short-segment Barrett's esophagus (SSBE) in a 36-year-old man. An elevated tumor was found at the esophagogastric junction, and a histological evaluation of the biopsy specimen led to a diagnosis of adenocarcinoma. The tumor was found to be confined to the mucosa surrounding the SSBE, and endoscopic submucosal dissection was done without complications. Histological examination of the resected specimen showed that the adenocarcinoma had also invaded the muscularis mucosae and provided evidence of lymphovascular invasion. Additional surgical resection and regional lymph node dissection were therefore carried out; however, no lymph node metastasis was found. Adenocarcinoma arising from Barrett's mucosa is rare in young patients, especially in Japan, and this case is therefore particularly noteworthy.

Multicenter study of the long-term outcomes of endoscopic submucosal dissection for early gastric cancer in patients 80 years of age or older.

BACKGROUND: Little information is available on the long-term outcomes of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) in patients of advanced age (≥80 years). METHODS: A multicenter study was conducted at 10 Japanese institutions concerning their results for ESD. Data on 440 patients of advanced age (≥80 years) with EGC (470 lesions) were collected and reviewed. Early and long-term outcomes of ESD were assessed. We compared the overall survival rates between 3 patient groups, those with curative ESD, additional surgery after noncurative ESD, and nonsurgical follow-up after noncurative ESD. RESULTS: Bleeding and perforation rates were 3.2 and 2.8%, respectively. Curative ESD was achieved in 366 of the 470 lesions (77.9%). Of the 104 patients with noncurative ESD, 12 patients (11.5%) underwent additional surgery and 91 patients (87.5%) were followed without surgery. The 5-year survival rate in the patients with nonsurgical follow-up after noncurative ESD (66.7%) was significantly lower than that in the patients with curative ESD (80.3%, p = 0.0001). There was no significant difference in the 5-year survival rates between the patients with curative ESD and those with surgery after noncurative ESD (100%, p = 0.21), nor was there a difference in these rates between the patients with surgery after noncurative ESD and those with nonsurgical follow-up after noncurative ESD (p = 0.061). None of the patients developed cancer recurrence after curative ESD, and none developed cancer recurrence following the additional surgery after noncurative ESD. In the patients with curative ESD and in those with surgery after noncurative ESD, the cumulative observed survival was better than the expected survival for the general population of similar age and gender. CONCLUSIONS: ESD is safe for the treatment of EGC in patients 80 years of age or older. Both curative ESD and additional surgery after noncurative ESD may contribute to the extension of life expectancy.

Determining early gastric cancer lesions appropriate for endoscopic submucosal dissection trainees: a proposal related to curability.

Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer. Our objective was to discuss the limited ESD reports available and to determine the lesions suitable for use in training endoscopists on which lesions are appropriate for ESD. We reviewed a series of ESD reports that have been written on various risk factors related to the resectability or curability of a variety of lesions. These published studies show that certain risk factors such as tumor size and location and the presence of ulceration are closely related to both resectability and curability. Because the combination of these risk factors resulted in a much higher risk than did any single factor, we recently established a 'risk assessment chart' to determine an individual's total risk of treatment failure for early gastric cancer that has been treated using ESD. This risk chart provides a clear indication that small, non-ulcerated lesions located in the lower third of the stomach have a high rate of curative resection and are technically less challenging if ESD is used. We suggest that trainees should gain ESD experience with such lesions before they start to perform ESD on more difficult lesion types that have a lower probability of curative resection. In addition, we suggest that this risk assessment chart is suitable for the pretreatment assessment of curability and the likelihood of successful en bloc resection.

Risk assessment chart for curability of early gastric cancer with endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer, but curability prediction has not been evaluated on an individual basis. OBJECTIVE: To analyze factors contributing to the curability of early gastric cancer after ESD and to construct a risk assessment chart for the probability of curability. DESIGN: Single-institution retrospective review. SETTING: University hospital. PATIENTS: From June 2000 to April 2010, we treated 961 early gastric cancers in 784 patients (mean age 70.2 years). INTERVENTION: ESD procedures were performed using typical sequences. MAIN OUTCOME MEASUREMENTS: Risk factors related to resectability (en bloc or piecemeal resection) and curability (curative or noncurative resection) after ESD were analyzed using logistic regression analysis. Using this model, we constructed a risk assessment chart to predict the probability of noncurability from patient characteristics. RESULTS: The en bloc and curative resection rates were 98.9% and 88.1%, respectively, after ESD. Significant contributors to noncurative ESD were large lesions, upper location, and ulcer findings. Predicted noncurability probabilities were displayed in 4 colors for each risk level (light blue, blue, yellow, and red) by combining tumor size, tumor location, and ulcer findings. Probability of noncurability was highest (≥ 40%) in ulcerative large tumors (>30 mm in diameter) in the upper location (red) and lowest in nonulcerative small tumors (≤ 20 mm in diameter) in the lower location (light blue). LIMITATIONS: Retrospective design and single-site data collection. CONCLUSIONS: This risk assessment chart shows individuals their pretreatment curability assessment with successful ESD and may be an educational tool for trainees or a decision-making tool.

Superficial adenocarcinoma of the esophagogastric junction: long-term results of endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) was recently introduced as a treatment option for superficial adenocarcinoma of the esophagogastric junction (EGJ); however, its long-term clinical outcomes have not been fully evaluated. OBJECTIVE: To assess the long-term outcomes of ESD for patients with superficial adenocarcinoma of the EGJ. DESIGN: Retrospective review from a single institution. SETTING: University hospital. PATIENTS: Fifty-eight patients, 46 men and 12 women (mean 69.3 years), with 39 T1m and 19 T1sm adenocarcinomas of the EGJ treated from June 2000 to May 2009. INTERVENTIONS: ESD procedures were performed with typical sequences. MAIN OUTCOME MEASUREMENTS: Complications, en bloc resection rate, curative resection rate, local recurrence, and distant metastases after ESD were evaluated. Curative resection is histologically defined as being free of resection margins and any evidence of deep submucosal invasion, undifferentiated carcinoma, and lymphovascular invasion. RESULTS: There were no major complications except for 3 patients with ulcer bleeding without the need for blood transfusion and 1 patient with esophageal stenosis. The rates of en bloc resection and curative resection were 100% and 79%, respectively. Twelve resections were histologically considered noncurative; these patients underwent additional ESD (n = 1) or surgical resection (n = 8). Local or distant recurrences were not observed in any patient achieving curative resection during follow-up (median 36.6 months, range 4-94 months). LIMITATIONS: Retrospective design and single-site data collection. CONCLUSIONS: Long-term outcomes after ESD are favorable. ESD may be adopted as a treatment of choice for superficial adenocarcinoma of the EGJ.

Successful initial ablation therapy contributes to survival in patients with hepatocellular carcinoma.

AIM: To evaluate the outcome predictors of percutaneous ablation therapy in patients with unresectable hepatocellular carcinoma (HCC), especially to identify whether the initial treatment response contributes to the survival of the patients. METHODS: The study cohort included 153 patients with single (102) and two or three (51) HCC nodules 5 cm or less in maximum diameter. As an initial treatment, 110 patients received radiofrequency ablation and 43 patients received percutaneous ethanol injection. RESULTS: The Kaplan-Meier estimates of overall 3- and 5-year survival rates were 75% and 59%, respectively. The log-rank test revealed statistically significant differences in the overall survivals according to Child-Pugh class (P = 0.0275), tumor size (P = 0.0130), serum albumin level (P = 0.0060), serum protein induced by vitamin K absence or antagonist II level (P = 0.0486), and initial treatment response (P = 0.0130). The independent predictors of survival were serum albumin level (risk ratio, 3.216; 95% CI, 1.407-7.353; P = 0.0056) and initial treatment response (risk ratio, 2.474; 95% CI, 1.076-5.692; P = 0.0330) based on the Cox proportional hazards regression models. The patients had a serum albumin level 3.5 g/dL and the 3- and 5-year survival rates of 86% and 82%. CONCLUSION: In HCC patients treated with percutaneous ablation therapy, serum albumin level and initial treatment response are the independent outcome predictors.

Impact of the early detection of esophageal neoplasms in hypopharyngeal cancer patients treated with concurrent chemoradiotherapy.

AIMS: We examined the risk factors and prognostic factors for synchronous esophageal neoplasia (SEN) by comparing the characteristics of hypopharyngeal cancer (HPC) patients with and without SEN. METHODS: We examined 183 patients who were treated with definitive radiotherapy for HPC. Lugol chromoendoscopy screening of the esophagus was performed in all patients before chemoradiotherapy. RESULTS: Thirty-six patients had SEN, 49 patients died of HPC and two died of esophageal cancer. The patients with SEN exhibited significantly higher alcohol consumption than those without SEN (P = 0.018). The 5-year overall survival (OS) rate of the 36 patients with SEN was lower than that of the other patients (36.2% vs 63.4%, P = 0.006). The SEN patients exhibited significantly shorter HPC cause-specific survival than the other patients (P = 0.039). Both the OS (P = 0.005) and the HPC cause-specific survival (P = 0.026) of the patients with SEN were significantly shorter than those of the patients without SEN in multivariate analysis. Category 4/T1 stage esophageal cancer was treated with concurrent chemoradiotherapy (CCRT), endoscopic treatment or chemotherapy. The 5-year survival rates for esophageal cancer recurrence for CCRT, endoscopic treatment and chemotherapy were 71.5, 43.7 and 0%, respectively. The median (range) survival time (months) of CCRT, endoscopic treatment and chemotherapy was 22.7 (7.5-90.6), 46.44 (17.3-136.7) and 7.98 (3.72-22.8), respectively. CONCLUSION: Advanced HPC patients with SEN might have a poorer prognosis than those without SEN even when the esophageal cancer is detected early and managed appropriately.

The Superiority of Vonoprazan-based First-line Triple Therapy with Clarithromycin: A Prospective Multi-center Cohort Study on Helicobacter pylori Eradication.

Objective We evaluated the safety and efficacy of vonoprazan-based amoxicillin and clarithromycin 7-day triple therapy (VAC) in comparison to proton pump inhibitor (PPI)-based (PAC) as a first-line treatment and vonoprazan-based amoxicillin and metronidazole 7-day triple therapy (VAM) in comparison to PPI-based (PAM) as a second-line treatment for the eradication of Helicobacter pylori in Japan. Methods We performed a non-randomized, multi-center, parallel-group study to compare first-line VAC to PAC and second-line VAM to PAM. A pre-planned subgroup analysis on CAM resistance was also performed. Safety was evaluated with an adverse effects questionnaire (AEQ), which was completed by patients during therapy. Results The first-line eradication rates (ER) in the intention-to-treat (ITT) and per protocol (PP) analyses were 84.9% (95% CI: 81.9-87.6%, n=623) and 86.4% (83.5-89.1%, n=612), respectively, for VAC and 78.8% (75.3-82.0%, n=608) and 79.4% (76.0-82.6%, n=603), respectively, for PAC. The ER of VAC was higher than that of PAC in the ITT (p=0.0061) and PP analyses (p=0.0013). The ERs for VAC in patients with CAM-resistant and CAM-susceptible bacteria were 73.2% (59.7-84.2%, n=56) and 88.9% (83.4-93.1%, n=180), respectively. PAC was associated with higher AEQ scores for diarrhea, nausea, headache, and general malaise. In the second-line ITT and PP analyses VAM achieved ERs of 80.5% (74.6-85.6%, n=216) and 82.4% (76.6-87.3%, n=211), respectively, while PAM achieved ERs of 81.5% (74.2-87.4%, n=146) and 82.1% (74.8-87.9%, n=145), respectively. No significant differences were observed in the ITT (p=0.89) or PP (p=1.0) analyses. Conclusion The ER of first-line VAC was higher than that of PAC, but still <90%. No difference was observed between second-line VAM and PAM. Vonoprazan-based triple therapy was safe and well tolerated.

[Radiofrequency ablation and percutaneous ethanol injection in patients with unresectable hepatocellular carcinoma--a comparative study using Japan Integrated Staging Score (JIS score) system].

The patients were classified according to the Japan Integrated Staging (JIS) score and a comparison examination of the long-term therapeutic response of 149 unresectable hepatocellular carcinomas: 90 of them given percutaneous ethanol injection (PEI), and 59 of them given radiofrequency ablation (RFA) who were diagnosed with 3 cm or less in diameters of tumor and less than three nodules, or 5 cm or less single nodule, was carried out in retrospective. To all the tumors exceeding 3 cm in diameter, we added transcatheter arterial embolization (TAE) prior to PEI or RFA. Ninety four percent of PEI cases and 25% of RFA cases received a combination therapy with TAE, respectively. The three-year survivals were 86%, 76%, and 56% in PEI and 96%, 83%, and 68% in RFA for JIS-0, 1, and 2, respectively. The five-year survivals were 69% and 53% in PEI and 95% and 83% in RFA for JIS-0 and 1, respectively. The significant difference in the probability of survival was not confirmed among both treatments. We conclude that the combination therapy, such as combined use of TAE, PEI and RFA as local treatment, can expect almost equivalent effectiveness for unresectable hepatocellular carcinoma.

Coagulation syndrome: Delayed perforation after colorectal endoscopic treatments.

Various procedure-related adverse events related to colonoscopic treatment have been reported. Previous studies on the complications of colonoscopic treatment have focused primarily on perforation or bleeding. Coagulation syndrome (CS), which is synonymous with transmural burn syndrome following endoscopic treatment, is another typical adverse event. CS is the result of electrocoagulation injury to the bowel wall that induces a transmural burn and localized peritonitis resulting in serosal inflammation. CS occurs after polypectomy, endoscopic mucosal resection (EMR), and even endoscopic submucosal dissection (ESD). The occurrence of CS after polypectomy or EMR varies according previous reports; most report an occurrence rate around 1%. However, artificial ulcers after ESD are largely theoretical, and CS following ESD was reported in about 9% of cases, which is higher than that for CS after polypectomy or EMR. Most cases of post-polypectomy syndrome (PPS) have an excellent prognosis, and they are managed conservatively with medical therapy. PPS rarely develops into delayed perforation. Delayed perforation is a severe adverse event that often requires emergency surgery. Since few studies have reported on CS and delayed perforation associated with CS, we focused on CS after colonoscopic treatments in this review. Clinicians should consider delayed perforation in CS patients.

Radiofrequency ablation in a pig liver model: effect of transcatheter arterial embolization on coagulation diameter and histologic characteristics.

To determine whether transcatheter arterial embolization (TAE) can alter radiofrequency (RF)-induced coagulation necrosis, we evaluated the morphology and histologic characteristics of RF ablation lesions combined with TAE in normal pig liver. Using a RF ablation system, consisting of a RF generator and 2-cm expandable LeVeen needle electrodes, nine lesions were generated by RF ablation combined with TAE and 11 lesions by RF ablation alone in five animals. On completion of treatment, the lesions were excised for gross and histologic examination. Gross examination demonstrated a core of ablated tissue surrounded by a narrow rim of hemorrhagic necrosis. The final shape of the lesion in the RF ablation group was frequently altered by patent intrahepatic vessels at the periphery of the lesion, whereas the lesions in the RF ablation and TAE group were spherical (P<0.05, chi(2)-test). The coagulation diameter was significantly larger in the RF ablation and TAE group than in the RF ablation group (28.7+/-4.2 vs. 24.1+/-3.2 mm, P<0.05). Histochemical (lactate-dehydrogenase, maleate-dehydrogenase and NADPH-diaphorase) stainings showed what appeared to be 100% cellular destruction in the ablated lesion and its hemorrhagic rim in both groups. We conclude that RF ablation combined with TAE induces greater and more spherical areas of coagulation necrosis in normal pig liver tissue than RF ablation alone.

Hepatocellular carcinoma: percutaneous radiofrequency ablation using expandable needle electrodes and the double-insertion technique.

The authors present a case of percutaneous radiofrequency ablation for the treatment of a confirmed hepatocellular carcinoma using expandable needle electrodes and the double-insertion technique. The patient underwent radiofrequency ablation for a 5.0-cm-in-diameter hepatocellular carcinoma in liver segment VIII. One radiofrequency ablation session using the double-insertion technique was performed, resulting in the complete necrosis of the tumor. A collection of pleural effusion as a complication of radiofrequency ablation was revealed by a computed tomography scanning which was performed after the radiofrequency ablation session. However, no other serious complication was encountered. No local recurrences have been observed after a 10-month follow-up period. The present case suggests the therapeutic efficacy of radiofrequency ablation using expandable needle electrodes and the double-insertion technique.

Hepatocellular carcinoma: a case of extrahepatic seeding after percutaneous radiofrequency ablation using an expandable needle electrode.

A 2.5-cm diameter, exophytic seeding of hepatocellular carcinoma was detected by contrast-enhanced computed tomography in a 76-year-old man. He had previously undergone a radiofrequency ablation therapy with an expandable, ten-hook needle electrode for the treatment of a 1.5-cm hepatocellular carcinoma in liver segment VI. Ultrasound-guided fine needle biopsy revealed that this hepatocellular carcinoma was moderately differentiated, as initial tumor was. An additional radiofrequency ablation achieved complete ablation of this neoplastic mass on contrast-enhanced computed tomography scanning. Recurrences were not found for eight months after. To prevent tumor seeding, using thermocoagulation when retracting the needle electrode may be useful.

[Radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinoma--CT examination during the follow-up period].

Radiofrequency ablation (RFA) combined with transcatheter arterial embolization (TAE) can increase the volume of coagulation necrosis to treat patients with hepatocellular carcinoma. Furthermore, in clinical practice, RFA combined with TAE using iodized oil and gelatin sponge often induced the sub-segmental or segmental necrosis toward the liver periphery of the ablated lesion. In this study, we compared the CT findings and histological characteristics of peripherally spreading necrosis induced by this combination therapy for 12 patients with hepatocellular carcinoma. In all cases, complete necrosis of ablated lesions and peripherally spreading necrotic areas were confirmed by CT examination. The histochemical (lactate-dehydrogenase, maleate-dehydrogenase, and NADPH-diaphorase) stained specimens, biopsies from ablated lesions and peripherally spreading necrotic areas, were absent suggesting a 100% cellular destruction. No incomplete local treatments after the therapy were obtained during the 4-26 months of follow-up periods. We conclude that RFA combined with TAE using iodized oil and gelatin sponge makes it possible to induce the segmental or sub-segmental necrosis including tumors.

[A case of AFP-producing gastric cancer with multiple liver metastases responding to CPT-11 and cisplatin combination chemotherapy].

A case of AFP-producing gastric cancer successfully treated with CPT-11 and cisplatin combined therapy is reported together with a review of the literature. A 52-year-old male was admitted with complaints of upper abdominal pain and body weight loss. Gastric cancer with multiple liver metastases was diagnosed based on endoscopy and computed tomography findings. The patient's serum AFP level was 697,100 ng/ml and a biopsy specimen showed AFP-positive tumor cells immunohistochemically. He was treated with a combination chemotherapy consisting of CPT-11 (70 mg/m2) on day 1 and 15, and cisplatin (80 mg/m2) on day 1, repeated every 4 weeks. The primary lesion of the stomach and the liver metastases were remarkably reduced, and the serum level of AFP decreased to 18 ng/ml after 5 cycles of this treatment. No severe side effects were seen during this treatment. This result suggests that combination chemotherapy consisting of CPT-11 and cisplatin may be effective and safe for patients with AFP-producing gastric cancer with multiple liver metastases.

Extension of radiofrequency ablation of the liver by transcatheter arterial embolization with iodized oil and gelatin sponge: results in a pig model.

PURPOSE: To determine whether transcatheter arterial embolization (TAE) with iodized oil and gelatin sponge particles can be used to expand radiofrequency (RF)-induced coagulation necrosis, the morphology and histologic characteristics of ablation lesions were evaluated in the normal pig liver after three different TAE procedures. MATERIALS AND METHODS: Ten consecutive animals with 33 ablation lesions produced with an RF ablation system were randomly assigned to one of three treatment groups and a control group: a group treated with TAE with iodized oil, a group treated with TAE with gelatin sponge, a group treated with TAE with iodized oil and gelatin sponge, and a control group in which TAE was not performed. After the completion of ablation, the lesions were excised for gross and histologic examination. RESULTS: The longest and shortest diameters of ablation lesions were greatest in the group treated with TAE with iodized oil and gelatin sponge, followed by the groups treated with TAE with gelatin sponge and TAE with iodized oil (P < .05 vs controls, respectively). The hemorrhagic rim was also widest in the group treated with TAE with iodized oil and gelatin sponge (P < .05 vs controls), and it spread toward the liver periphery like a segmental hemorrhagic area adjacent to the ablation lesion. Histochemical staining for lactate dehydrogenase, maleate dehydrogenase, and nicotinamide adenine dinucleotide diaphorase showed what appeared to be 100% cellular destruction in all the ablation lesions and their hemorrhagic rims. CONCLUSION: RF ablation combined with TAE with iodized oil and gelatin sponge induces the greatest area of coagulation necrosis accompanied by peripherally spreading segmental necrosis in normal pig liver tissue.

Retrograde transvenous obliteration of gastric varices associated with large collateral veins or a large gastrorenal shunt.

Balloon-occluded retrograde transvenous obliteration of gastric varices by a microcatheter insertion method was performed in eight patients with large collateral veins or a large gastrorenal shunt. A 3-F microcatheter was selectively inserted into the gastric varices through a 6-F balloon catheter wedged in the left adrenal vein. Selective venography of the gastric varices and injection of the sclerosing agent, a mixture of 10% ethanolamine oleate and iopamidol, through the microcatheter system without occluding the collateral veins was accomplished in one treatment session in all patients. There have been no complications or recurrences of gastric varices in any of the patients during the follow-up period.