Tsutomu Namieno

Solitary cystic tumor of the pancreas: EUS-pathologic correlation

BACKGROUND It is clinically important to distinguish neoplastic from non-neoplastic pancreatic cysts. METHODS Retrospective correlations were made between pathologic and EUS data from 52 pancreatic solitary cystic tumors: mucinous cystadenoma (10), mucinous cystadenocarcinoma (7), serous cystadenoma (5), ductectatic mucinous cystic tumor (10), solid and papillary epithelial neoplasm (5), and non-neoplastic cyst (15). The mean tumor size was 3.5 cm (range, 1.2 cm to 6.0 cm). RESULTS Six classifications of the internal structures of these cysts were developed: thick wall type, tumor protruding type, thick septal type, microcystic type, thin septal type, and simple type. Although all neoplastic cysts belonged to the first four types, all non-neoplastic cysts belonged to the last two types. The accuracy of EUS for differentiating tumors was estimated at 96% and 92%, respectively, by two observers. CONCLUSIONS EUS may become a mandatory modality for differentiating pancreatic solitary cystic tumors and choosing an optimal treatment.

Efficacy and safety of preoperative percutaneous transhepatic portal embolization with absolute ethanol: A clinical study

BACKGROUND Preoperative portal embolization has been performed by using various thrombogenic substances to increase the safety and resectability of liver surgery. We evaluated the clinical safety and efficacy of using absolute ethanol in preoperative portal embolization. METHODS Our study included 19 patients who had undergone right hepatic lobectomy. According to our criteria for right lobectomy of the liver, seven patients were not appropriate for the operation because of a high risk in each of postoperative liver failure. Those patients received preoperative right portal embolization with 11 to 32 ml absolute ethanol. The remaining 12 patients satisfied our criteria and received no preoperative embolization. RESULTS Although alanine aminotransferase concentrations increased dramatically after the embolization, all serologic changes reverted within 3 weeks. The mean volume of the nonembolized lobe increased from 320 cm3 to 619 cm3 and 667 cm3 2 and 4 weeks, respectively, after embolization. The mean regeneration rate of this lobe was 21.3 cm3 per day for the first 2 weeks and 11.4 cm3 per day for the first 4 weeks after embolization. All patients underwent right lobectomy of the liver and survived; none of the patients had severe complications associated with embolization or surgery. The postoperative survival periods were not statistically significant between the patients with and without preoperative portal embolization. CONCLUSIONS According to our criteria for liver surgery, the seven patients should not have undergone major surgery, but each underwent right lobectomy of the liver and all survived, showing that portal embolization with absolute ethanol brings about compensatory hepatic hypertrophy for major surgery and that its extreme effect on liver regeneration could widen the range of patients appropriate for liver surgery.

Adjuvant chemoimmunotherapy for hepatocellular carcinoma patients. Adriamycin, interleukin-2, and lymphokine-activated killer cells versus adriamycin alone.

To determine improved postresection survival in patients with hepatocellular carcinoma, two postoperative protocols were compared: adoptive Chemoimmunotherapy versus chemotherapy. Following resection, 24 patients were allocated at random to receive (1) arterial infusion of Adriamycin. re-combinant interlcukin-2 and lymphokine-activated killer cells or (2) arterial infusion of Adriamycin alone. The spleen was removed at operation and used to prepare lymphokine-activated killer cells. Each group had 12 patients. They were followed until signs of recurrence appeared. The overall survival rates of the patients were 91.7%, 82.9%, and 72.5% at 1, 2, and 3 years, respectively, and slightly higher than would be expected with surgery alone. No statistically significant difference was found between the two groups either in the survival rate (generalized Wilcoxon test, P = .936) or in the cumulative disease free rate (P = .182). However, when patients who had had hepatic resection with negative margin (≥1 cm) were separated, the 2-year cumulative disease-free rate in the adoptive Chemoimmunotherapy was higher (83.3%, n = 6) than that in chemotherapy (37.5%, n = 8). Toxicity to adoptive Chemoimmunotherapy was moderate; no severe side effects were observed. Totally no statistical difference between the two groups was found. Although only one of six patients in adoptive Chemoimmunotherapy experienced recurrence after hepatic resection with negative margin, it was not feasible to determine the role of interleukin-2 and lymphokine-activated killer cells. We conclude that the adoptive Chemoimmunotherapy in this study is not an ideal adjuvant protocol after hepatic resection.

Congenital Arteriovenous Malformation of the Pancreas : Its Diagnostic Features on Images

To analyze diagnostic features on images of congenital arteriovenous malformation (AVM) of the pancreas, we analyzed the diagnostic findings in six patients with the disease, using gray-scale ultrasonography (US), color Doppler US, computed tomography, and angiography and analyzed previously reported cases. AVM characteristic findings on images were multiple, small hypoechoic nodules on US, mosaic appearance of the lesion and pulsatile wave form in the portal vein on color Doppler US, conglomerated small nodular enhancement of the lesion and early appearance of the portal vein on CT, and a racemose network and early appearance of the portal vein on angiography. Five of the six patients underwent surgery, and all resected specimens were histologically found to be AVMs of the pancreas; however, one with developed portal hypertension at surgery died of repeated bleeding from esophageal varices. From analysis of total of 35 cases including our six cases, a mosaic appearance of the lesion was found in 100% and a pulsatile wave form in the portal vein in 77.8% on color Doppler US. Color Doppler US is noninvasive and useful for detecting congenital AVM of the pancreas at an early stage, preventing the portal hypertension causing esophageal varices and their rupture.

Treatment of experimental tumors with a combination of a pulsing magnetic field and an antitumor drug

We investigated the effects of a combination treatment involving a pulsing magnetic field (PMF) and an antitumor drug, mitomycin C (MMC), on two experimental tumors (fibrosarcoma KMT‐17 and hepatocellular carcinoma KDH‐8) in WKA rats, paying attention to possible potentiation of the therapeutic effect of the antitumor drug. PMF was obtained using a system generating a pulsed current in a solenoid coil. On day 7 after tumor implantation into the right thighs of rats, the region of the tumor was exposed to PMF (frequency 200 Hz, mean magnetic flux density 40 gauss) for 1 h immediately after iv injection of MMC at a dose of 1 mg/kg. Survival rates at day 90 of KMT‐17 implanted rats were 0% (0/10) in the non‐treated group, 34% (4/12) in the MMC‐treated group, 47% (6/13) in the PMF‐treated group and 77% (10/13) in the MMC/PMF combination group. The increase of life span (ILS) of KDH‐8‐implanted rats in the combination therapy group was significantly prolonged (%ILS 17.6%) compared with that in the MMC‐treated (%ILS 3.4%) and PMF‐treated (%ILS 7.6%) groups. By using cultured cells of the above two lines of tumor, the therapeutic effects of MMC and PMF were also determined from the cell colony‐forming efficiency in soft agar. The colony‐forming efficiencies of both cell lines were significantly suppressed in the combination therapy group compared with those in the other single therapy groups. The present results indicate that PMF exhibited a potentiation of the antitumor effect of mitomycin C.

General Pattern of Lymph Node Metastasis in Early Gastric Carcinoma

Abstract. A reliable method for recognizing lymph node metastasis is indispensable for the attending physician to recommend less extensive treatment for early gastric carcinoma. Here we review 1137 consecutive patients with a single primary lesion, and the incidence and distribution of nodal involvement were investigated for correlations with pathologic findings. The overall incidence of metastasis was 9.5%: 2.6% for mucosal and 16.5% for submucosal carcinomas, a significant difference. The occurrence of metastasis was highest for lesions of the macroscopically mixed type, microscopically diffuse type, and large size. The involved nodes were most frequently found in the perigastric nodes along the lesser and greater curvatures, and it was well correlated with the tumor location, macroscopically depressed/mixed type, cancer depth, and histology. The diffuse-type carcinomas were most likely to metastasize to distant nodes. The distribution of involved nodes for early gastric carcinoma was similar to that for advanced carcinoma, as previously been reported. The submucosal carcinomas in this series had no indications for less extensive treatment, such as endoscopic or laparoscopic limited surgery. These carcinomas should be subject to standard surgery with gastrectomy and combined dissection of lymph nodes, especially node stations 1 and 3 to 8. The mucosal carcinomas sometimes involved the perigastric nodes, and such cases underwent gastrectomy and lymphadenectomy of node stations 1 and 3 to 7. Mucosal carcinomas 10 mm or less in size were negative for lymph node metastasis and were considered appropriate for less extensive treatment.

Assessing the Suitability of Gastric Carcinoma for Limited Resection: Endoscopic Prediction of Lymph Node Metastases

Abstract. Some early gastric carcinomas are free of lymph node involvement; however, the pathosis of these carcinomas is neither well understood nor reflected in the choice of less extensive treatment. We investigated the relation of nodal involvement to pathologic findings of the resected specimens. We present promising standards for predicting the nodal status of early gastric carcinomas, contributing to the indication for limited surgery. The relation of lymph node metastasis to tumor size, infiltration depth, macroscopic appearance, and histologic type of early gastric carcinomas were investigated in 1470 patients with a single primary early gastric carcinoma. Of these carcinomas, 763 were limited to the mucosa (mucosal carcinoma) and 707 to the submucosa (submucosal carcinoma). The overall incidence of lymph node metastasis was 9.0%:2.1% in mucosal carcinomas and 16.5% in submucosal ones, with a significant (p < 0.001) difference of nodal involvement between the two. The macroscopically elevated or compound-type carcinomas 10 mm or less in diameter were all node-negative, whereas some depressed-type carcinomas were node-positive. The incidence of undifferentiated carcinomas increased with tumor diameter, irrespective of whether they were mucosal or submucosal carcinomas, and they were significantly more node-positive than were differentiated carcinomas: p< 0.001 for mucosal carcinomas and p < 0.05 for submucosal ones. The carcinomas satisfying the following criteria are node-negative and eligible for limited surgery: (1) mucosal carcinoma; (2) elevated lesion <10 mm in diameter; (3) differentiated adenocarcinoma; and (4) no ulcer or ulcer scar. The other carcinomas are potentially node-positive and standard surgery is recommended.

Diagnosis of arteriovenous malformation of the pancreas by color Doppler ultrasonography

Arteriovenous malformation (AVM) of the pancreas is a rare disease, and once this silent disease develops portal hypertension it is too difficult for the physician to successfully control the disease. AVM is usually diagnosed by invasive diagnostic modalities, and noninvasive modalities should be developed for its diagnosis. We have experienced two cases of AVM of the pancreas, which were located at the pancreatic head and diagnosed by color Doppler ultrasonography (Doppler US). The two AVM lesions were detected as a mosaic pattern, and the lesions were connected to the main portal vein on Doppler US; the pulsatile waves were also observed in the mosaic lesions by the analysis of the Doppler spectrum. We determined the two patients suffered from congenital AVM of the pancreas, since they had no abnormal findings on past and physical histories, laboratory data, and other images. One patient refused surgery, and another underwent pancreatoduodenectomy. Histology of the resected specimen demonstrated the lesion was AVM of the pancreas. These cases support that the present modality is useful for the diagnosis of the pancreatic AVM as a noninvasive procedure, and we discuss the usefulness of noninvasive Doppler US which shows not only static but also hemodynamic informations.

Pancreas: imaging diagnosis with color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography

Recent advances of ultrasound imaging have made possible to depict various diseases and conditions of the pancreas. Color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography are feasible to show vascular abnormalities, differentiate the solid and cystic tumors, decide tumor extent, and help to perform interventional treatments of the pancreatic diseases. Those techniques will contribute to the more precise and easier diagnosis and to prompt decision of the treatments of the pancreatic disorders. Radiologists should recognize the diagnostic feasibility and limitations of those techniques in order to avoid unnecessary examinations on the patients, and obtain precise diagnostic images.

Assessing the suitability of gastric carcinoma for limited resection: histologic differentiation of endoscopic biopsy.

Abstract. Histologically differentiated adenocarcinoma satisfies one of the criteria for limited surgery for mucosal carcinoma of the stomach; however, the histology of the endoscopic biopsy specimen is often different from that of the resected specimen. The medical records of 1018 early gastric carcinomas were retrospectively analyzed to investigate the relation between the histologies of biopsy and resected specimens. Regression analysis showed that the histologies of biopsy specimens were significantly related to those of resected specimens (r= 0.916,n= 5, p= 0.0288) for the mucosal carcinomas, but their relation was not significant for the submucosal carcinomas (r= 0.677, n= 5,p= 0.2091). By analyzing the 344 differentiated mucosal carcinomas, moderately differentiated tubular adenocarcinomas were seen to be frequently less differentiated at resection. The histology of the biopsy specimens from mucosal carcinoma of the stomach grossly satisfies one of the criteria for limited surgery, but moderately differentiated adenocarcinoma may not be suitable for this treatment.