An artificial intelligence-based nerve recognition model is useful as surgical support technology and as an educational tool in laparoscopic and robot-assisted rectal cancer surgery.

BACKGROUND: Artificial intelligence (AI) has the potential to enhance surgical practice by predicting anatomical structures within the surgical field, thereby supporting surgeons' experiences and cognitive skills. Preserving and utilising nerves as critical guiding structures is paramount in rectal cancer surgery. Hence, we developed a deep learning model based on U-Net to automatically segment nerves. METHODS: The model performance was evaluated using 60 randomly selected frames, and the Dice and Intersection over Union (IoU) scores were quantitatively assessed by comparing them with ground truth data. Additionally, a questionnaire was administered to five colorectal surgeons to gauge the extent of underdetection, overdetection, and the practical utility of the model in rectal cancer surgery. Furthermore, we conducted an educational assessment of non-colorectal surgeons, trainees, physicians, and medical students. We evaluated their ability to recognise nerves in mesorectal dissection scenes, scored them on a 12-point scale, and examined the score changes before and after exposure to the AI analysis videos. RESULTS: The mean Dice and IoU scores for the 60 test frames were 0.442 (range 0.0465-0.639) and 0.292 (range 0.0238-0.469), respectively. The colorectal surgeons revealed an under-detection score of 0.80 (± 0.47), an over-detection score of 0.58 (± 0.41), and a usefulness evaluation score of 3.38 (± 0.43). The nerve recognition scores of non-colorectal surgeons, rotating residents, and medical students significantly improved by simply watching the AI nerve recognition videos for 1 min. Notably, medical students showed a more substantial increase in nerve recognition scores when exposed to AI nerve analysis videos than when exposed to traditional lectures on nerves. CONCLUSIONS: In laparoscopic and robot-assisted rectal cancer surgeries, the AI-based nerve recognition model achieved satisfactory recognition levels for expert surgeons and demonstrated effectiveness in educating junior surgeons and medical students on nerve recognition.

Mini-Laparotomy for Superior Mesenteric Artery Aneurysm Due to Takayasu's Arteritis.

Superior mesenteric artery aneurysm (SMAA) is reported to be the third-most common type of visceral aneurysm (VA), accounting for 5% of all VAs. The etiology of SMAA is commonly thought to be infection, and it usually exists in the proximal part of the superior mesenteric artery, which is suitable for endovascular treatment. We herein report an extremely rare case of the distal part of SMAA caused by Takayasu's arteritis (TA), which was successfully resected using a mini-laparotomy method without impairing the intestinal blood supply. A 51-year-old woman was admitted to our hospital with sustained fever and lower back pain. Physical examination showed that she had a discrepancies in blood pressure between both arms. Contrast-enhanced whole-body computed tomography showed stenosis of the thoracic aorta and an aneurysm located in the distal part of the superior mesenteric artery. The diameter of the aneurysm was 4.5 cm. The aneurysm was resected via 4-cm mini-laparotomy, and the vascularity of the intestine was successfully preserved. The postoperative course was uneventful, and the patient was diagnosed as having TA based on both clinical and pathologic findings. Additional corticosteroid therapy was started to treat the arteritis, and at 3-month follow-up she was without critical incidents. Mini-laparotomy is a safe and less-invasive approach to treat SMAA, especially when the lesion is located in the distal part of the artery.

Aspartate aminotransferase-to-platelet ratio index is associated with liver cirrhosis in patients undergoing surgery for hepatocellular carcinoma.

BACKGROUND: Among various preoperative evaluations of liver function, accurate assessment of liver cirrhosis (LC) is especially important in patients undergoing surgery for hepatocellular carcinoma (HCC). OBJECTIVE: To explore the most significant laboratory parameter associated with LC in patients undergoing surgery for HCC. METHODS: From among 588 HCC patients in our collected database who underwent liver surgery, 371 for whom sufficient laboratory data were evaluable, including direct serum fibrosis markers such as hyaluronic acid and type 3 procollagen peptide (P-3-P), were enrolled. Receiver operating characteristic (ROC) curve analysis was used to define the ideal cutoff values of laboratory parameters, and the area under the ROC curve for LC was measured. Univariate and multivariate analyses were performed to clarify the laboratory parameter most significantly associated with LC. RESULTS: Multivariate analysis of 13 laboratory parameters that had been selected by univariate analysis showed that the aspartate aminotransferase-to-platelet ratio index (APRI) (≤ 0.8/>0.8) (odds ratio, 2.687; 95% confidence interval 1.215-5.940; P = 0.015) was associated with LC, along with the aspartate aminotransferase to alanine aminotransferase ratio, the indocyanine green retention ratio at 15 min (ICG R15), and the level of hyaluronic acid. Among these four parameters associated with LC, ROC curve analysis revealed that APRI (0.757) had the largest area under the ROC (aspartate aminotransferase to alanine aminotransferase 0.505, ICG R15 0.714, and hyaluronic acid 0.743). CONCLUSIONS: APRI is closely associated with LC in patients undergoing surgery for HCC.

Usefulness of a new inflammation-based scoring system for prognostication of patients with hepatocellular carcinoma after hepatectomy.

BACKGROUND: We investigated whether a preoperative scoring system (the "CRP-AFP Score [CAS]") based on the serum levels of C-reactive protein and alpha-fetoprotein would predict outcome in patients undergoing hepatectomy for hepatocellular carcinoma. METHODS: The CAS was defined as follows: patients with an elevated level of both C-reactive protein (>.3 mg/dL) and alpha-fetoprotein (>20 ng/mL) were assigned a score of 2, and patients showing one or none of these abnormalities were assigned a score of 1 or 0, respectively. RESULTS: A total of 349 patients were identified. Pathologic findings, in terms of tumor size, histologic grade, vascular invasion, intrahepatic metastasis, and recurrence rate, worsened as the CAS increased. CAS 2 patients had a poorer 5-year overall survival than CAS 0 or 1 patients (32.2% vs 59.7% vs 49.2%, respectively; P < .001). CONCLUSIONS: The CAS is an informative scoring system that can predict outcome in patients with hepatocellular carcinoma after hepatectomy.

Intraductal papillary neoplasm of the bile duct developing in a patient with primary sclerosing cholangitis: a case report.

We report a case of intraductal papillary neoplasm of the bile duct (IPNB) that developed in a patient with primary sclerosing cholangitis. A 46-year-old woman was admitted to our hospital with obstructive jaundice. The liver function tests demonstrated increased serum liver enzyme levels. Computed tomography showed dilatation of the intrahepatic bile ducts. Abdominal ultrasonography revealed a highly echoic protruding lesion in the posterior bile duct near the right lobe of the liver. The lesion was suspected to be IPNB, but we were unable to confirm whether it was a carcinoma. A right hepatectomy was performed, and this showed that the dilated bile duct was filled with mucin and contained several yellowish papillary tumors. Histologically, the neoplastic biliary epithelium showed papillary growth in the dilated lumen. The tumor was diagnosed as IPNB, high-grade intraepithelial neoplasia secreting abundant mucin. No recurrence has been detected 3 years after surgery.

Inflammation-based prognostic score predicts biliary stent patency in patients with unresectable malignant biliary obstruction.

BACKGROUND: An inflammation-based prognostic score, the modified Glasgow prognostic score (mGPS), has been reported to be useful for predicting postoperative survival in patients with various types of cancer. However, no studies have investigated whether the mGPS can predict biliary stent (BS) patency in patients undergoing BS placement for unresectable malignant biliary obstruction (UMBO). AIM: To evaluate the usefulness of the mGPS for predicting BS patency in patients undergoing intraoperative placement of uncovered expandable metallic stents (EMSs) for UMBO. PATIENTS AND METHODS: The mGPS was calculated as follows: patients with both an elevated C-reactive protein (CRP) level (>1.0 mg/dl) and hypoalbuminemia (<3.5 g/dl) were allocated a score of 2. Patients with only an elevated CRP level were allocated a score of 1, and patients without an elevated CRP level were allocated a score of 0. EMS patency was compared by Kaplan-Meier analysis and log-rank test between the two groups (mGPS 0 vs. mGPS 1 or 2). The significant risk factors for EMS occlusion were investigated by Cox proportional hazards model analysis. RESULTS: Kaplan-Meier analysis revealed that patients with mGPS 1 (n=7) and 2 (n=19) had a lower EMS patency rate (p=0.014) than patients with mGPS 0 (n=37). Although univariate analyses revealed that a high serum total bilirubin level, stent-in-stent placement, and mGPS 1 or 2 were significant risk factors predictive of EMS occlusion, multivariate analysis demonstrated that no independent risk factors were significant. CONCLUSION: mGPS is a significant predictor of EMS patency in patients undergoing intraoperative placement of BS.

When hepatic-side ductal margin is positive in N+ cases, additional resection of the bile duct is not necessary to render the negative hepatic-side ductal margin during surgery for extrahepatic distal bile duct carcinoma.

BACKGROUND: The current standard treatment for extrahepatic distal bile duct carcinoma (EDBDC) is surgical resection, as no effective alternative treatment exists. In this study, we investigated the treatment strategies and outcomes for 90 cases of EDBDC at our department. MATERIAL AND METHODS: Between April 2000 and March 2013, 90 pancreatoduodenectomies (PDs) were performed for EDBDC. The mean patient age was 69.1 ± 9.8 years, and there were 59 males and 31 females. Extended lymph adenectomy including lymph nodes around the common hepatic artery and celiac axis was performed in all patients. The mean operation time was 537.1 ± 153.8 min and the mean operative blood loss was 814.0 ± 494.0 ml. There were no operation-related deaths. The overall 1-, 3-, and 5-year survival rates were 90.0%, 51.2%, and 45.0%, respectively. RESULTS: Lymph node metastasis was present in 28 patients (N+; 31.1%), and it was absent in 62 (N-; 68.9%). The 5-year survival rate was 20.0% for N+ patients and 52.4% for N- patients, which is significantly higher (P=0.03). Nine cases (10.0%) showed hepatic-side ductal margin (HM) positivity for carcinoma. The 5-year survival rate was 18.7% for HM-positive patients and 48.3% for HM-negative patients, which is significantly higher (P=0.005). In multivariate analysis, N+ was the strongest adverse prognostic factor. Subclass analysis of 62 cases (excluding 28 N+ cases) revealed 7 patients with positive HMs (11.3%) and 55 patients with negative HMs (88.7%). The 5-year survival rate was 47.6% for HM-positive patients and 49.8% for HM-negative patients (P=0.73). Thirty-five cases (38.9%) recurred: there were 19 cases of local recurrence (21.1%), 11 cases of liver metastasis (12.2%), 4 cases of distant recurrence (4.4%), and 1 case of para-aortic lymph node metastasis (1.1%). CONCLUSIONS: In conclusion, when HM is positive in N+ cases, additional resection of the bile duct is not necessary to render the HM negative for carcinoma.

Outcome of hepatectomy for hepatocellular carcinoma in elderly patients with portal hypertension.

The outcome of liver resection (LR) for elderly hepatocellular carcinoma (HCC) patients with portal hypertension (PHT) who may be excluded as liver transplantation candidates has not been fully evaluated. One hundred ninety-five patients who underwent initial curative LR for HCC with PHT were divided into 2 groups: age <70 years (n = 131) and age ≥70 years (n = 64). Clinicopathologic data and postoperative complications were compared. Preoperative characteristics and postoperative complications were similar in both groups. However, in-hospital mortality was significantly more frequent in elderly than in younger patients (11% versus 1%, P = 0.002). No significant intergroup differences were observed in the 5-year disease-free survival rate or recurrence rate (19.7% versus 17.2%; P = 0.338, 63% versus 56%; P = 0.339). Although LR for elderly HCC patients with PHT can be performed with curative intent and gives results comparable with those in younger patients, it is associated with higher in-hospital mortality.

Usefulness of an inflammation-based prognostic score (mGPS) for predicting survival in patients with unresectable malignant biliary obstruction.

BACKGROUND: An inflammation-based prognostic score, the modified Glasgow Prognostic Score (mGPS), has been established as a useful tool for predicting postoperative outcome in patients with cancer. However, no studies have investigated the usefulness of the mGPS for prognostication in patients undergoing palliative surgery for unresectable malignant biliary obstruction (UMBO). The present study was conducted to investigate whether the mGPS is useful for predicting the postoperative survival of patients undergoing intraoperative placement of an expandable metal stent for UMBO, or not. METHODS: The mGPS was calculated as follows: patients with both an elevated level of C-reactive protein (CRP) (>1.0 mg/dL) and hypoalbuminemia (<3.5 g/dL) were allocated a score of 2. Patients with only an elevated CRP level were allocated a score of 1, and patients without an elevated CRP level (≤1.0 mg/dL) were allocated a score of 0. Postoperative survival was evaluated by Kaplan-Meier analysis and log rank test. The significance of risk factors for postoperative survival was evaluated with the Cox proportional hazards model. RESULTS: Kaplan-Meier analysis revealed that patients with mGPS 0 (n = 36) and 1 (n = 7) had better postoperative survival (p = 0.017) than patients with mGPS 2 (n = 17). The 6-month and 1-year survival rates of patients with mGPS 0 and 1 were 58.1 and 27.3 %, and those for patients with mGPS 2 were 25.0 and 6.2 %, respectively. Multivariate analysis revealed that mGPS (0, 1/2) was a significant risk factor for postoperative survival (hazard ratio 3.271; 95 % CI 1.109-9.649; p = 0.032). CONCLUSION: The mGPS is not only one of the most significant predictors of postoperative survival for UMBO patients receiving intraoperative biliary stenting but also a useful indicator capable of dividing such patients into two independent groups before surgery.

Survival after surgery for hepatocellular carcinoma in relation to presence or absence of viral infection.

BACKGROUND: The aim of this study was to compare postoperative survival between hepatocellular carcinoma (HCC) patients with and without viral infection. METHODS: From among 398 HCC patients in our collected database, 377 who underwent surgery were enrolled. The patients were divided into 2 groups: group 1, those who had no hepatitis B virus or hepatitis C virus infection, and group 2, those who had hepatitis B virus or hepatitis C virus infection. Univariate analysis was performed to compare clinical factors, including viral infection, with overall survival. Kaplan-Meier analysis and the log-rank test were used to evaluate the overall and disease-free survival curves for the 2 groups. RESULTS: Univariate analysis showed that viral infection showed no such association. Moreover, Kaplan-Meier analysis and the log-rank test revealed no significant intergroup differences in either overall or disease-free survival. CONCLUSIONS: The presence or absence of viral infection shows no significant association with the postoperative survival of patients undergoing surgery for HCC.

Effect of billroth II or Roux-en-Y reconstruction for the gastrojejunostomy on delayed gastric emptying after pancreaticoduodenectomy: a randomized controlled study.

OBJECTIVE: Delayed gastric emptying (DGE) is one of the major complications after pancreaticoduodenectomy (PD), occurring in 14% to 61% of cases. There have been no studies that compare the incidence of DGE in terms of the reconstruction method of gastrojejunostomy performed in subtotal stomach-preserving pancreaticoduodenectomy (SSPPD). The objective of this study was to evaluate the superiority of Billroth II (B-II) to Roux-en Y (R-Y) reconstruction on decreasing the incidence of delayed gastric emptying DGE after SSPPD by a prospective randomized controlled trial. METHODS: Between April 2008 and August 2011, 101 patients who underwent SSPPD for pancreatic head or periampullary diseases were randomly allocated to B-II reconstruction (n = 52) and R-Y reconstruction (n = 49) groups. The primary endpoint was incidence of DGE. RESULTS: DGE occurred in 5.7% of patients in the B-II group and in 20.4% of patients in the R-Y group (P = 0.028). Patients in the B-II group had a significantly shorter hospital stay after operation than patients in the R-Y group (31.6 ± 15.0 days vs. 41.4 ± 20.5 days, P = 0.037). In terms of postoperative complications, the incidence of pancreatic fistula was significantly higher in patients with DGE (38.5%) than in patients without DGE (14.8%) (P = 0.037). CONCLUSION: It is suggested that the incidence of DGE after SSPPD can be decreased by using B-II rather than R-Y reconstruction for gastrojejunostomy.(Clinical Trials Registry, UMIN-CTR: http://www.umin.ac.jp/ctr/, ref no. UMIN000003535).

Patient with adult-onset type II citrullinemia beginning 2 years after operation for duodenal malignant somatostatinoma: Indication for liver transplantation.

We report a 51-year-old female patient with adult-onset type II citrullinemia (CTLN2) who had a history of pancreatoduodenectomy for duodenal somatostatinoma with metastases to regional lymph nodes at age 49 years, paying special attention to indications for liver transplantation. At age 50 years, she developed hepatic encephalopathy with elevation of plasma ammonia and citrulline levels. A diagnosis of CTLN2 was made by DNA analysis of the SLC25A13 gene and treatment with conservative therapies was begun, including a low-carbohydrate diet and supplementation with arginine and sodium pyruvate. However, despite these treatments, frequent attacks of encephalopathy occurred with markedly elevated plasma ammonia levels. While we were apprehensive regarding the risk of recurrence of somatostatinoma due to immunosuppressive therapy after liver transplantation, the patient was in a critical condition with CTLN2 and it was decided to perform living-donor liver transplantation using a graft obtained from her son. Her postoperative clinical course was uneventful and she has had an active life without recurrence of somatostatinoma for 2 years. This is the first case of CTLN2 with somatostatinoma. As the condition of CTLN2 patients with rapidly progressive courses is often intractable by conservative therapies alone, liver transplantation should be considered even after surgery for malignant tumors in cases with neither metastasis nor recurrence.

Single-stage intraoperative transhepatic biliary stenting in patients with unresectable hepatobiliary pancreatic tumors.

BACKGROUND: The current study was conducted to evaluate the safety and utility of intraoperative transhepatic biliary stenting (ITBS) in patients with unresectable malignant biliary obstruction (UMBO) diagnosed intraoperatively. METHODS: In this study, 50 patients who underwent ITBS for UMBO between April 2001 and May 2009 were retrospectively reviewed. For 26 patients who underwent preoperative percutaneous transhepatic biliary drainage (PTBD), the expandable metallic stent (EMS) was inserted intraoperatively by the PTBD route in a single stage. For 24 patients, the intrahepatic bile ducts were intentionally dilated by injection of saline via the endoscopic nasobiliary drainage or the percutaneous transhepatic gallbladder drainage route, and the puncture was performed under intraoperative ultrasound guidance followed by guidewire and catheter insertion. Thereafter, the EMS was placed in the same manner. The initial postoperative complications and long-term results of ITBS were evaluated. RESULTS: In all cases, ITBS was technically successful. Stenting alone was performed in 22 patients and stenting combined with other procedures in 28 patients. Hospital mortality occurred for three patients (6 %), and complication-related mortality occurred in two cases (4 %). There were nine cases (18 %) of postoperative complications. The median survival time was 179 days, and the EMS patency time was 137 days. During the follow-up period, EMS occlusion occurred in 23 cases (46 %). Best supportive care was a significant independent risk factor for early mortality within 100 days after ITBS (p = 0.020, odds ratio, 9.398). CONCLUSIONS: Single-stage ITBS is feasible for palliation of UMBO and seems to have a low complication rate.

Results of pancreaticoduodenectomy with portal or superior mesenteric vein resection for locally advanced pancreatic head cancer.

BACKGROUND/AIMS: It is known that portal vein (PV) or superior mesenteric vein (SMV) is easily invaded by locally advanced pancreatic head cancer due to anatomical characteristics. Few studies have investigated the results of PD with PV or SMV resection (PVR) for pancreatic head cancer. METHODOLOGY: We retrospectively reviewed a database of 83 patients who had undergone PD for pancreatic head cancer (PC). We divided them into two groups, a group with PD and PVR (PD +PVR G) and a group with PD and no PVR (PD -PVR G). The clinicopathological findings and mortality were analyzed. RESULTS: Twenty-nine of the 83 patients (34.9%) needed PD with PVR. Median survival and disease free survival were 20.4 months and 10.6 months, respectively. The 5-year overall survival rate was 8.1% in PD +PVR G and 7.4% in PD -PVR G, respectively. There was no difference between the two groups (p = 0.091, HR: 1.576; 95% CI: 0.9299-2.670). The 5-year disease free survival rate was 9.6% in PD +PVR G and 10.2% in PD -PVR G, respectively. Also, there was no difference between the two groups (p = 0.206, HR: 1.414; 95% CI: 0.8264-2.420). CONCLUSIONS: Since PVR by itself is not a risk factor of postoperative morbidity and mortality and contributes to improving 5-year overall survival and disease free survival, PVR should be done for selected cases with locally advanced pancreas head cancer.

Discrepancy of B cell frequency between periphery and spleen after rituximab treatment in ABO-incompatible liver transplantation.

ABO-incompatible living-donor liver transplantation (ABO-LDLT) is generally more difficult to perform than ABO-incompatible kidney transplantation. Despite introduction of rituximab, ABO-LDLT in non-responders is a still difficult issue. A 23-year-old woman with primary sclerosing cholangitis underwent LDLT. The recipient's blood type was 0(+) and the donor's was B(+). Rituximab was infused twice on preoperative day (POD) 14 and 7. Plasma exchange (PE) was performed on PODs 5, 3, 2, and 1. However, repeated PE failed to decrease the anti-B antibody titer. On the other hand, preoperative esophagogastroscopy revealed esophageal varices with red color sign. Therefore, simultaneous liver transplantation and Hassab operation were performed. The donor left lobe of the liver was orthotopically transplanted into the recipient following Hassab operation. Flow cytometry on the day of surgery showed that the frequencies of B cells (CD20+) and memory B cells (CD20+/CD27+) in the peripheral blood were 0.9% and 0.3%, respectively; flow cytometry of cells recovered from the spleen revealed that the frequencies of B cells and memory B cells were 2.5% and 2.4%, respectively. Acute cellular rejection occurred on POD 15, and was treated by steroid pulse therapy, leading to a decrease in the anti-B antibody titer. The liver was functioning well on POD 390 (AST 19, ALT 34). In non-responders to ABO-LDLT, anti-donor blood type antibody-producing cells remains in the spleen after the conventional preoperative regimen. Splenectomy is an option for ABO-LDLT non-responders.

Effect of menatetrenone, a vitamin k2 analog, on recurrence of hepatocellular carcinoma after surgical resection: a prospective randomized controlled trial.

The aim of this study was to investigate whether menatetrenone (MNT) suppresses hepatocellular carcinoma (HCC) recurrence in patients undergoing hepatectomy. Between January 2005 and September 2009, 101 patients who underwent curative hepatectomy for primary HCC were enrolled in the study. Patients were divided into two groups: a non-MNT group (n=51), and an MNT group (n=50) that was administered 45 mg of MNT daily. During the observation period, recurrence was observed in 33 patients in the non-MNT group and in 28 patients of the MNT group (p=0.545). In patients with a preoperative Des-γ-carboxy-prothrombin (DCP) level lower than 40 AU/l (n=38), the cumulative disease-free survival rates at 12, 36, and 60 months in the non-MNT group, were 81.3%, 0.0%, and 0.0%, respectively, while those in the MNT group were 78.3%, 58.1%, and 31.0%, respectively (p=0.060). MNT has a moderately suppressive effect on HCC recurrence after hepatectomy, especially in patients with a normal preoperative DCP level.

Surgical inflammation induces hepcidin production after abdominal surgery.

BACKGROUND: Hepcidin, a key regulator of iron homeostasis, is also a marker of acute inflammation. In the present study we investigated the changes in the serum hepcidin level and correlations between hepcidin and other markers of acute inflammation during the perioperative period in patients after abdominal surgery. METHODS: Serum hepcidin, hemoglobin (Hb), hematocrit (Ht), white blood cell (WBC) count, frequency of neutrophils, and C-reactive protein (CRP) were measured preoperatively (Pre), and on postoperative days (POD) 1, 3, 7, and 14. RESULTS: In patients undergoing gastrectomy, the median levels of hepcidin preoperatively and on POD 1, 3, 7, and 14 were 6.5, 53.1, 31.7, 15.6, and 4.0 ng/dl, respectively (p < 0.0001). The corresponding levels in colectomy patients were 8.5, 78.3, 60.1, 49.7, and 8.4 ng/dl, respectively (p = 0.0002); those in hepatectomy patients were 6.6, 16.3, 3.5, 13.4, and 3.4 ng/dl, respectively (p = 0.0022); and those in patients undergoing surgery for diffuse peritonitis were 24.8, 50.1, 43.1, 31.2, and 31.7 ng/dl, respectively (p = 0.4933). There were no significant decreases in Hb and Ht in the patients undergoing gastrectomy, colectomy, or surgery for diffuse peritonitis. The level of hepcidin was significantly correlated with the WBC count, frequency of neutrophils, and CRP level during the perioperative period for all four types of operation. CONCLUSIONS: Like other inflammatory markers, an increase in the level of hepcidin (i.e., a hepcidin storm) occurs in the acute phase after gastrectomy, colectomy, hepatectomy, and surgery for diffuse peritonitis.

Body mass index is a risk factor of pancreatic fistula after pancreaticoduodenectomy.

Pancreatic fistula (PF) after pancreaticoduodenectomy (PD) is still a severe complication and a challenging problem. The common risk factors are the soft pancreas and small pancreatic duct of the remnant pancreas. Those two risk factors were recognized during surgery. On the other hand, a preoperatively determined risk factor of PF is unclarified. We conducted a retrospective analysis of 203 patients consecutively treated by PD from April 2000 to October 2010. PF was defined according to the criteria of the International Study Group of Pancreatic Fistula. Clinical and pre- and intraoperative data were compared between PF and non-PF patients. The recommended cutoff value of body mass index (BMI) as 20 kg/m(2) was defined by receiver operating characteristic curve analysis. PF occurred in 53 (26.1%) of 203 patients. In univariate analysis, BMI and soft remnant pancreas were found to be risk factors of PF (P = 0.027, P = 0.005). In multivariate analysis, BMI and soft pancreas were also risk factors of PF (P = 0.040, P = 0.005). Patients with PF had a significantly longer hospital stay than non-PF patients (P = 0.005). High BMI and soft pancreas were significant risk factors for PF.

Intraoperative observation using a fluorescence imaging instrument during hepatic resection for liver metastasis from colorectal cancer.

BACKGROUND/AIMS: We have found that liver metastasis from colorectal cancer (LM-CRC) can be easily detected by its fluorescence using a fluorescence imaging instrument (photodynamic eye (PDE)) in patients who have received an intravenous injection of indocyanine green (ICG). Therefore, our aim is to demonstrate the usefulness of PDE observation for hepatic resection in patients with LM-CRC. METHODOLOGY: Between February and October 2009, seven patients who underwent hepatic resection for LM-CRC were enrolled. After previous ICG injection (0.1mg/kg/mL), PDE observation was performed to detect fine invisible residual tumors on the surface of the resected liver. RESULTS: All of the 46 resected LM-CRCs that had been pointed out preoperatively were easily detected by their fluorescence using PDE observation. Three of the seven patients underwent additional partial resection because fine invisible residual tumors were detected by their fluorescence using PDE observation. All of these patients who underwent additional resection had no recurrence of LMCRC on the surface of the resected liver after surgery. CONCLUSIONS: PDE observation is useful for detecting fine invisible residual tumors that cannot be revealed under visible light during hepatic resection in patients with LM-CRC and may reduce the incidence of local recurrence on the superficial parenchyma of the liver.