Kazuhiro Yamashiro

Lack of Survival Benefit of Extended Lymph Node Dissection for Ductal Adenocarcinoma of the Head of the Pancreas: Retrospective Multi-institutional Analysis in Japan

Abstract. It has not been established that extended lymph node resection is necessary for ductal adenocarcinoma of the head of the pancreas. According to the general rules for the study of pancreatic cancer, a multiinstitutional, retrospective clinical study was undertaken to investigate the efficiency of extended lymph node dissection for this malignancy. Altogether 501 patients underwent resection of the pancreas between 1991 and 1994 at 77 medical facilities; the surgical procedures, staging, lymph node dissection, curability, and survival rate were analyzed retrospectively. Eighteen of the patients died within 30 postoperative days, leaving 483 patients to be studied. The resection was curative microscopically in 94 patients, resulting in a 3-year survival of 29%. Macroscopically curative resection resulted in a 3-year survival of 14%; noncurative resection produced a 3-year survival of 6%. Although extended lymph node dissection was performed on 38 patients in stage I, 42 patients in stage II, 206 patients in stage III, and 1 patient in stage IV, there was no improvement in survival when the results were compared to those seen after standard or palliative lymph node dissection. The extent of lymph node dissection has not affected the prognosis for ductal adenocarcinoma of the head of the pancreas at any stage of the course of the disease. Excessive lymph node dissection in advanced cases does not necessarily lead to a favorable prognosis. The patients who undergo a radical operation with an adequate lymph node dissection have longer survivals.

Changes in portal hemodynamics and hepatic function after partial splenic embolization (PSE) and percutaneous transhepatic obliteration (PTO)

Since April 1985, we have performed a multidisciplinary therapy consisting of partial splenic embolization (PSE), percutaneous transhepatic obliteration (PTO) or transileocolic vein obliteration (TIO), and endoscopic injection sclerotherapy (EIS) for patients with severe gastroesophageal varices and those with a portacaval shunt associated with portal hypertension. In this study, PSE and percutaneous transhepatic portography (PTP) were performed at the same time in seven liver cirrhosis patients with hypersplenism, gastroesophageal varices, or hepatocellular carcinoma. The changes in portal blood flow/pressure and hemodynamics were examined by a thermodilution method. The effects of PSE on blood biochemical parameters such as the platelet count, ICG R15, redox tolerance index (RTI), and oral glucose tolerance test (75 g OGTT) were also evaluated. PSE induced a decrease in the blood flow of the splenic artery and in the splenic vein pressure without decreasing the portal blood flow. The platelet count in the peripheral blood and the RTI increased significantly. These results suggest the possibility that PSE may reduce the potential perioperative risk in hepatocellular carcinoma complicated with liver cirrhosis.

Beneficial effects of administering intraportal prostaglandin E1 postoperatively to hepatectomy patients with massive intraoperative blood loss

Massive intraoperative blood loss is a major cause of complications following hepatectomy. To evaluate the efficacy of intraportal prostaglandin E1 (PGE1) for preventing liver deterioration in hepatectomy patients with an intraoperative blood loss of over 2000 ml, a retrospective analysis was conducted on 10 patients given intraportal PGE1 (portal group), 6 given intravenous PGE1 (venous group), and 10 given no treatment (control group). PGE1 was infused at 250 or 500 μg/day in the portal group and at 720 μg/day in the venous group, and continued for 3 days postoperatively. Alanine aminotransferase (ALT) and total bilirubin (T.Bil) were measured on postoperative days (PODs) 1, 3, 5, and 7. ALT was lower in the portal group than in the other two groups on each POD, and significantly lower than in the control group on POD 3 (P<0.05). T.Bil was significantly lower in the portal group than in the control group on PODs 5 and 7 (P<0.05). T.Bil on POD 7 was under 1.5 mg/dl in 1 (10.0%), 6 (60.0%), and 2 (33.3%) of the control, portal, and venous group patients, respectively, with a significant difference between the control and portal groups (P<0.05). These results confirmed that intraportal PGE1 was beneficial for improving hepatic function and preventing cholestasis in patients with a blood loss of over 2000 ml at risk of developing postoperative liver deterioration.

The anatomy of the parapancreaticoduodenal vessels and the introduction of a new pylorus‐preserving pancreatoduodenectomy with increased vessel preservation

Classical pancreaticoduodenectomy for malignant tumors of the pancreatoduodenal region or chronic pancreatitis has recently been discussed in terms of the quality of life, associated with long-term postoperative morbidity. Pylorus-preserving pancreatoduodenectomy (PPPD) for the patient with chronic pancreatitis was first reported by Traverso and Longmire. Since that time, PPPD has become an accepted surgical procedure that is being increasingly indicated for certain malignancies. Herein, we report a PPPD that also preserves the parapancreatoduodenal vessels. The reasons why PPPD with the preservation of these vessels is significant are related to the length of the preserved duodenum and the reactions of gastrointestinal hormones. However, it may appear that this new PPPD poses a little greater risk of cancer recurrence, since the surgery is less radical than the usual PD. If the indications listed below are strictly observed, this operation should enable. The indications are: (1) chronic pancreatitis with tumor formation in the pancreatic head, (2) ampullary carcinoma, (3) inferion biliary duct carcinoma, (4) early duodenal carcinoma (all without pancreatic invasion), and (5) certain benign cystic tumors. Whether this operation should also be recommended for patients with small carcinomas or islet cell tumors arising in the head of the pancreas is now being investigated.

Partial splenic embolization in patients with liver cirrhosis and hepatocellular carcinoma: Effects on portal hemodynamics

Partial splenic embolization (PSE) was performed on patients with liver cirrhosis to control hypersplenism and gastroesophageal varices. In this study, we evaluated the effects of PSE on the portal hemodynamics and hepatic function of 17 cirrhotic patients with hepatocellular carcinoma. The mean splenic volume and the peak platelet count increased significantly and the splenic vein pressure decreased significantly after PSE. However, the portal blood flow did not change. Changes in the 15-min retention rate of indocyanine green and the arterial ketone body ratio were not significant, but the redox tolerance index increased from 0.24 ± 0.28 × 10−2 to 0.59 ± 0.35 × 10−2. These results suggest that PSE may reduce perioperative risks in cirrhotic patients with hepatocellular carcinoma who are candidates for hepatic resection.

Monitoring perioperative hepatic venous oxygen saturation (ShvO2) in hepatectomy—Changes of ShvO2 in hemorrhagic shock

Hepatic venous oxygen saturation (ShvO2) is an indicator of the hepatic oxygen supply-to-demand ratio, which can be used to estimate adequate hepatic blood flow if hepatic oxygen is constant. We monitored ShvO2 intraoperatively and postoperatively in a patient who underwent right hepatic lobectomy. Decreases in ShvO2 were noted during surgical maneuvers which included manipulation of the hepatic hilum and mobilization of the liver. The ShvO2 recovered immediately after termination of these procedures. After the operation the patient developed hypovolemic shock due to postoperative bleeding; blood pressure dropped from 120 to 90 mmHg and the ShvO2 fell from 70% to 30%. Dopamine (5μg/kg per min) was administered to maintain the blood pressure. Temporary cessation of the dopamine infusion caused a decrease in ShvO2 (from 85% to 75%) without a major change in blood pressure. Dopamine increases hepatic blood flow, and accordingly, this decrease in ShvO2 must have been caused by cessation of the dopamine infusion. This finding suggests that ShvO2 can be used to determine optimal dopamine dosage for maintaining hepatic blood flow. From these observations, ShvO2 accurately reflects changes in hepatic blood flow and ShvO2 monitoring was helpful in avoiding hepatic ischemia during the periperative period in a patient undergoing a hepatectomy. Unexpected changes in hepatic blood flow can be immediately identified by monitoring ShvO2, enabling more rapid intervention.