[A Case of Non-Functioning Pancreatic Neuroendocrine Tumor Accompanied by Stenosis of the Main Pancreatic Duct].

We experienced a rare case of pancreatic neuroendocrine tumor(pNET)in which stenosis of the main pancreatic duct occurred despite the tumor diameter being less than 1 cm; therefore, here, we report this case with some literature review.A 41-year-old woman showed dilation of the main pancreatic duct on an abdominal ultrasound as part of a health examination, and she visited our department for a more detailed examination.Enhanced CT scan showed a 7mm subtle enhancing mass in the head of the pancreas and the upstream main pancreatic duct was dilated up to 7 mm.ERCP and MRCP images also showed a dilated main pancreas duct.We suspected that her tumor was a pNET.We decided not to perform surgery immediately. After 6 months of follow-up, the tumor size increased to 10 mm; therefore, we performed subtotal stomach-preserving pancreaticoduodenectomy considering the possibility of pancreatic cancer.Histopathological findings showed that the pancreatic tumor had the property of a neuroendocrine tumor and the proliferated fibrous stroma around it caused the pancreas duct stenosis.

[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.

Evaluation using contrast-enhanced harmonic gray scale sonography after radio frequency ablation of small hepatocellular carcinoma: sonographic-histopathologic correlation.

OBJECTIVE: To evaluate the usefulness of contrast-enhanced harmonic wideband gray scale sonographic images obtained after radio frequency-induced coagulation necrosis, we compared the morphologic and histopathologic characteristics of the ablated tumors with sonographic images of the tumors. METHODS: Forty-eight patients with 72 hepatocellular carcinomas with a maximal diameter of 3 cm or less were treated percutaneously using radio frequency ablation. Six treated tumors in 4 patients were resected 1 month after ablation; the remaining 66 treated tumors were evaluated by a biopsy procedure performed with an 18-gauge fine needle 1 month after ablation. The excised tumors and biopsy specimens were then examined by histopathologic methods, and the findings were compared with those obtained on contrast-enhanced harmonic wideband gray scale sonography. Hematoxylin-eosin-stained specimens were inconclusive as to whether cellular viability remained; therefore, cell viability was determined by a positive result after histochemical (lactate dehydrogenase and nicotinamide adenine dinucleotide phosphate-diaphorase) staining. RESULTS: Contrast-enhanced harmonic wideband gray scale sonography after radio frequency ablation showed residual tumor enhancement in 5 (6.9%) of the 72 tumors; the histopathologic results for these 5 tumors were also positive for tumor residue. The remaining 67 tumors (93.1%) did not show any residual tumor enhancement when examined by sonography; however, only 66 tumors did not reveal tumor residue when examined histopathologically. Contrast-enhanced harmonic wideband sonographic imaging provided results that were comparable with histopathologic findings, the criterion standard for diagnosis; the sensitivity and specificity of the sonographic images for the detection of residual tumor tissue in ablated tumors were 83.3% (5 of 6) and 100% (66 of 66), respectively. CONCLUSIONS: Contrast-enhanced harmonic wideband gray scale sonography is a potentially useful technique for evaluating the therapeutic effects of radio frequency ablation on hepatocellular carcinoma.