Hitoshi Sekido

Risk Factors and Management of Bile Leakage after Hepatic Resection

The aim of this study was to identify the perioperative risk factors for postoperative bile leakage after hepatic resection and to propose a treatment strategy for such leakage when it does occur. Between 1992 and 2000 a total of 313 hepatic resections without choledocojejunal anastomosis were performed at our institute. Risk factors related to bile leakage were identified with univariate analysis, and strategies were evaluated in relation to the findings of postoperative fistulography. Postoperative bile leakage developed in 17 patients (5.4%). Univariate analysis identified high risk factors as advanced age, a wide surface area of the incision (bile leakage group versus no bile leakage group: 102.1 vs. 66.4 cm2, p < 0.05), and exposure of Glisson’s sheath at the cut surface (e.g., central bisegmentectomy, S4, S8 subsegmentectomy). Groupings of patients by their postoperative fistulography results showed that patients with involvement of the proximal bile duct were slower to heal than those with no demonstrable bile duct involvement. The one patient whose fistulogram demonstrated peripheral bile duct involvement had uncontrollable leakage and required reoperation. Hepatectomies with a wide surface area and those that expose the major Glisson’s sheath present serious risk factors for bile leakage. When the fistulogram shows proximal bile duct involvement, endoscopic nasobiliary tube drainage is necessary; when the fistulogram shows peripheral bile duct involvement, reoperation is needed.

Hepatic Resection Combined with Portal Vein or Hepatic Artery Reconstruction for Advanced Carcinoma of the Hilar Bile Duct and Gallbladder

Hepatectomy with vascular reconstruction for biliary malignancy remains controversial. This study aimed to clarify the indications for surgery. Patients with advanced hilar bile duct cancer (HBDC) (n = 26) and gallbladder cancer (GBC) involving the hepatoduodenal ligament (n = 13) who underwent hepatectomy were enrolled. They were divided into two groups on the basis of whether vascular reconstruction was performed (HBDC, 10 yes vs. 16 no; GBC, 5 yes vs. 8 no). Portal vein (PV) reconstruction was performed on the right branch in seven patients and on the left branch in two; hepatic artery (HA) reconstruction was done on the right branch in 11 patients and on the left branch in 1. Five patients with HBDC and one with GBC underwent both PV and HA reconstruction. Patency rates were 88.0% and 83.3% for PV and HA reconstructions, respectively. Vascular reconstruction-related morbidity occurred in one patient with fatal liver failure owing to a portal thrombus and in two patients with multiple liver abscesses caused by arterial obstruction. Microsurgery eliminated reconstruction-related morbidity. Mortality in vascular reconstruction cases was 13.3% (2/15), and in those without reconstruction it was 8.3% (2/24). Curability rates (R0 and R1+R2) were 50.0% and 56.0% for HBDC and 40.0% and 62.5% for GBC, respectively. The 3-year survivals of HBDC patients were, respectively, 33% and 42%, and the 5-year survivals were 18% and 25%, whereas for GBC the 1-year survivals were 20% and 60% and the 2-year survivals 0% and 25%. Two patients with vascular involvement who underwent PV with HA reconstruction survived more than 3 years. Hepatectomy with vascular reconstruction for selected HBDC patients offers low surgical risk and increased survival by curable resection, but it is not recommended for advanced GBC.

Minimum sizes for remnant and transplanted livers in rats

Our new technique of hepatectomy in rats, avoiding inferior vena cava constriction, revealed that 5%–10% of the total liver is the minimum required volume for remnant liver, a smaller amount than previously reported. The characteristic histological findings of remnant liver in perioperative death are marked hepatocytosis and hepatocyte apoptosis, and extensive hepatocyte necrosis with sinusoid congestion, all of which are thought to be caused by hyperendotoxemia and mitochondrial energy crisis. Partial liver transplantation in rats with our new technique of hepatectomy in the donor operation showed that a graft of 20% liver was the minimum required volume for successful transplantation, also a smaller amount than previously reported. There was no difference in the rate of increase in wet weight after surgery between 20% remnant liver and 20% transplanted liver. Differences between 10% minimum volume remnant liver and 20% minimum transplanted liver appeared to be caused by ischemia-reperfusion and cold preservation injury to the transplanted liver.

Metastatic Tumor Doubling Time: Most Important Prehepatectomy Predictor of Survival and Nonrecurrence of Hepatic Colorectal Cancer Metastasis

We determined the relative value of the metastatic colorectal cancer doubling time as a predictor of recurrence and survival after hepatectomy in comparison with other established predictors. Consecutive patients who underwent hepatic resection (n = 144) for colorectal cancer liver metastases were studied retrospectively to identify factors that influence overall survival and recurrence in the remnant liver. Overall 5-year survival and nonrecurrence rates were 49.8% and 50.8%, respectively. By multivariate analysis, large liver tumors (p = 0.038), p53 expression by the liver tumor (p = 0.011), and a short liver metastasis doubling time (≤ 45 days, p = 0.013) negatively affected survival; doubling times > 45 days (adjusted relative risk 0.06; p < 0.001) positively influenced disease-free survival. In patients with remnant liver recurrence, a short doubling time was associated with short disease-free intervals (7.3 ± 6.2 months), multiple metastases (63.6%), and fewer attempts at repeat hepatectomy (22.7%). The doubling time determines tumor size and reflects the patient’s immune and nutritional status. A short doubling time is the most reliable risk factor for multiple metastases, early recurrence, and poor prognosis. Further studies with a larger number of patients are needed to confirm this conclusion.

Anisakidosis: a cause of intestinal obstruction from eating sushi

We report a case of strangulating small bowel obstruction in a 60-yr-old Japanese woman caused by anisakidosis (previously known as anisakiasis). With the increasing popularity of Japanese cuisine such as sushi in the United States, the incidence of anisakidosis is expected to increase. Intestinal anisakidosis can now be treated temporarily, but this condition may cause a serious obstruction afterwards, as evidenced by this particular case. Over 13,500 cases were reviewed in both the Japanese and English literature, and we discuss the prevention of anisakidosis without negatively altering the taste of the raw fish.

Prognostic significance of the number of positive lymph nodes in gallbladder cancer

The aim of this study was to assess the prognostic impact of the number of lymph node metastases. The medical records of 33 patients with node-positive gallbladder cancer (GBC) treated at our institution from January 1985 through December 2002 were reviewed. There were 10 cases with a single node metastasis. The sites were as follows: the cystic duct node, the pericholedochal node, the retroportal node, the hilar node, the lymph node around the common hepatic artery, and the paraaortic node. According to the International Union Against Cancer (UICC) 5th edition, 5-year survival rates for the patients with pN1, pN2, and greater than pN2 were 19.2%, 10%, and 0%, respectively (not significant). Patients with a single node metastasis had a higher 5-year survival rate (33%) than patients with two or more lymph node metastases (0%; P<0.05). There were no lymph node recurrences in patients with a single node metastasis. Number of positive nodes and liver metastasis were factors predictive of significantly worse survival. Rather than using the topographic classification, or even simply classifying whether nodal involvement is positive or negative, classification according to the number of positive nodes will contribute to establishing a more practically useful staging system.

Procedures of Choice for Resection of Primary and Recurrent Liver Metastases from Colorectal Cancer

Although liver resection offers the only realistic chance of cure for patients with liver metastases from colorectal cancer, no consensus exists as to the procedure of choice for managing these tumors. Data from 193 patients who underwent hepatectomy for liver metastases from colorectal cancer and 26 of 193 patients who underwent repeat hepatectomy for recurrent metastases were collected. The suitability of resection was evaluated retrospectively based on known risk factors for recurrence and patterns of recurrence. On multivariate analysis, a positive surgical margin (SM+) was the only risk factor for recurrence after the initial resection (p < 0.01). SM+ (p < 0.01) and nonanatomic resection (p < 0·05) that was less than a sectionectomy (p < 0.05) were risk factors for recurrence after repeat hepatectomy. Multiple tumors (four or more) was the most common pattern of recurrence after initial hepatectomy, and recurrence close to the line of resection was most common after repeat hepatectomy. Based on tumor doubling times, recurrence after initial hepatectomy seemed to originate from the primary colorectal lesion, whereas recurrence after repeat hepatectomy was derived from a hepatic metastasis. Retrospective analysis suggests that hepatectomy with clear surgical margins is more important than anatomic resection for initial hepatectomy, and at least sectionectomy is necessary for repeat hepatectomy.

Efficacy of Hepatic Resection for Hepatocellular Carcinomas Larger than 10 cm

The objective of this study were to evaluate the efficacy of hepatic resection for large hepatocellular carcinomas (HCCs) and examine clinicopathologic factors influencing overall survival after resection of a large HCC. The pre-, intra-, and postoperative factors and long-term outcome of 26 patients with HCCs >10 cm who underwent hepatic resection (group A) were compared with the those of 143 patients with HCCs ≤10 cm (group B). Hepatic resection for large HCCs can be performed with a mortality rate of 3.8%, which was similar to the rate for group B (2.1%). The overall cumulative survival results for group A (1 year 41.0%, 3 years 29.3%, 5 years 29.3%; median survival 10.1 months) were markedly worse than those for group B (1 year 93.1%, 3 years 74.5%, 5 years 44.7%; median survival 53.4 months) (p < 0.0001). Multivariate analysis identified venous invasion as an independent risk factor of survival of patients with a large HCC. The overall cumulative survival results in patients with venous invasion (1 year 28.0%, 3 years 0%; median survival 6.4 months) were markedly worse than in patients without venous invasion (1 year 64.8%, 3.5 years 64.8%; median survival, 51.8 months) (p < 0.0066). We concluded that hepatic resection can be performed safely for HCCs >10 cm with a low mortality rate. It appears reasonable to believe that hepatic resection is the treatment of choice for large HCCs without venous invasion.

The role of splenomesenteric vein anastomosis after division of the splenic vein in pancreatoduodenectomy

Division of the splenic vein was performed in 29 patients who underwent pancreatoduodenectomy to achieve lymph node dissection and neural resection around the superior mesenteric artery. The basic protocol for the splenic vein reconstruction to reduce congestion of the spleen and stomach is as follows. When the inferior mesenteric vein (IMV) drained into the splenic vein, the confluence was preserved without reconstruction of the splenic vein. When the IMV drained into the superior mesenteric vein (SMV) or the splenomesenteric angle, the division of the IMV and spleno-IMV anastomosis were performed. In postoperative venography, nine patients showed downward flow (from the splenic vein to the IMV) and three patients showed upward flow (from the IMV to the splenic vein). Postoperative computed tomography scans showed venous dilatation and splenomegaly in the upward flow group; there were no patients in the downward flow group. In selected patients, splenic vein reconstruction is necessary to reduce congestion of the spleen and stomach. When the flow is downward, spleno-IMV flow should be preserved. When the flow is upward, spleno-SMV anastomosis is necessary instead of spleno-IMV anastomosis.

Microscopic liver metastasis: Prognostic factor for patients with pT2 gallbladder carcinoma

Hepatic metastasis is the most frequent mode of recurrence of advanced gallbladder cancer after radical resection. The aims of this study were to clarify the clinical significance of microscopic liver metastasis from pT2 gallbladder cancer and to clarify whether partial hepatectomy can prevent hepatic recurrence in patients with microscopic liver metastasis. The subjects included 20 patients with pT2 tumors who underwent radical surgery and partial hepatectomy with lymph node dissection. Microscopic liver metastasis was defined as a distant metastatic nodule including cancer cell nests in the lumen of the portal vein and discrete nodular lesions in the liver, all less than 5 mm in diameter. Cox’s proportional hazard regression was used to analyze factors that contributed to outcomes. Microscopic metastases were detected in the resected livers from 5 of 20 patients. There were more metastatic lesions within 1 cm of the gallbladder bed than were located 1 to 2 cm away from it. Microscopic liver metastases showed a strong correlation with the extent of blood vessel invasion around the primary tumor and were frequently detected in patients with a primary tumor localized on the hepatic side and with more than 3 cm of subserosal invasion. In four of five patients with microscopic liver metastases, recurrence was found in the remnant liver, which led to death within 15 months after the initial operation. Microscopic liver metastasis, operative curability, and lymph node metastasis were assessed as independent prognostic factors. A large proportion of patients with microscopic liver metastasis suffered from hepatic recurrence. Our results suggest that partial hepatectomy alone cannot prevent hepatic recurrence in patients with microscopic liver metastasis.