A clinical assessment of three-dimensional-printed liver model navigation for thrice or more repeated hepatectomy based on a conversation analysis.

PURPOSES: We performed a conversation analysis of the speech conducted among the surgical team during three-dimensional (3D)-printed liver model navigation for thrice or more repeated hepatectomy (TMRH). METHODS: Seventeen patients underwent 3D-printed liver navigation surgery for TMRH. After transcription of the utterances recorded during surgery, the transcribed utterances were coded by the utterer, utterance object, utterance content, sensor, and surgical process during conversation. We then analyzed the utterances and clarified the association between the surgical process and conversation through the intraoperative reference of the 3D-printed liver. RESULTS: In total, 130 conversations including 1648 segments were recorded. Utterance coding showed that the operator/assistant, 3D-printed liver/real liver, fact check (F)/plan check (Pc), visual check/tactile check, and confirmation of planned resection or preservation target (T)/confirmation of planned or ongoing resection line (L) accounted for 791/857, 885/763, 1148/500, 1208/440, and 1304/344 segments, respectively. The utterance's proportions of assistants, F, F of T on 3D-printed liver, F of T on real liver, and Pc of L on 3D-printed liver were significantly higher during non-expert surgeries than during expert surgeries. Confirming the surgical process with both 3D-printed liver and real liver and performing planning using a 3D-printed liver facilitates the safe implementation of TMRH, regardless of the surgeon's experience. CONCLUSIONS: The present study, using a unique conversation analysis, provided the first evidence for the clinical value of 3D-printed liver for TMRH for anatomical guidance of non-expert surgeons.

Development of real-time navigation system for laparoscopic hepatectomy using magnetic micro sensor.

BACKGROUND: We report a new real-time navigation system for laparoscopic hepatectomy (LH), which resembles a car navigation system. MATERIAL AND METHODS: Virtual three-dimensional liver and body images were reconstructed using the "New-VES" system, which worked as roadmap during surgery. Several points of the patient's body were registered in virtual images using a magnetic position sensor (MPS). A magnetic transmitter, corresponding to an artificial satellite, was placed about 40 cm above the patient's body. Another MPS, corresponding to a GPS antenna, was fixed on the handling part of the laparoscope. Fiducial registration error (FRE, an error between real and virtual lengths) was utilized to evaluate the accuracy of this system. RESULTS: Twenty-one patients underwent LH with this system. Mean FRE of the initial five patients was 17.7 mm. Mean FRE of eight patients in whom MDCT was taken using radiological markers for registration of body parts as first improvement, was reduced to 10.2 mm (p = .014). As second improvement, a new MPS as an intraoperative body position sensor was fixed on the right-sided chest wall for automatic correction of postural gap. The preoperative and postoperative mean FREs of 8 patients with both improvements were 11.1 mm and 10.1 mm (p = .250). CONCLUSIONS: Our system may provide a promising option that virtually guides LH.

Utility of modified pancreaticoduodenectomy (Hi-cut PD) for middle-third cholangiocarcinoma: an alternative to hepatopancreaticoduodenectomy.

BACKGROUND: The standard procedure for middle-third cholangiocarcinoma (MCC) is pancreaticoduodenectomy (PD); hepatopancreaticoduodenectomy (HPD) is often performed despite its high risk. There is no clear selection guidance for these procedures. METHODS: Patients with MCC who underwent HPD or PD were retrospectively evaluated. The conventional PD was modified (mPD) to transect the bile duct beyond or close to the cranial level of the portal bifurcation. RESULTS: The mPD group (n = 55) was characterized by older age, shorter operation time, less blood loss, and less frequent complications than were observed in the HPD group (n = 34). The median grossly tumor-free margin of the proximal bile duct (GM) was 13 mm vs 20 mm (P = 0.006). Overall survival did not differ significantly between groups (48% vs 53% at 5 years, P = 0.399). Multivariate analysis identified positive surgical margin as a sole independent prognostic factor (hazard ratio, 1.89; P = 0.043), which was statistically associated with GM length. Five-year survival for mPD patients with GM ≥15 mm was significantly better than that for those who had GM <15 mm (69% vs 33%, P = 0.011) and comparable to that of HPD patients (53%, P = 0.450). CONCLUSION: The mPD may be recommended in patients with MCC, provided that GM ≥15 mm is expected from the preoperative radiological imaging. Otherwise, HPD should be considered.

Early Prediction of a Serious Postoperative Course in Perihilar Cholangiocarcinoma: Trajectory Analysis of the Comprehensive Complication Index.

OBJECTIVE: The aim of this study was to visualize the postoperative clinical course using the comprehensive complication index (CCI) and to propose an early alarming sign for subsequent serious outcomes in perihilar cholangiocarcinoma. BACKGROUND: Surgery for this disease carries a high risk of morbidity and mortality. The developmental course of the overall morbidity burden and its clinical utility are unknown. METHODS: Patients who underwent major hepatectomy for perihilar cholan-giocarcinoma between 2010 and 2019 were reviewed retrospectively. All postoperative complications were evaluated according to the Clavien-Dindo classification (CDC), and the CCI was calculated on a daily basis until postoperative day 14 to construct an accumulating graph as a trajectory. Group-based trajectory modeling was conducted to categorize the trajectory into clinically distinct patterns and the predictive power of early CCI for a subsequent serious course was assessed. RESULTS: A total of 4230 complications occurred in the 484 study patients (CDC grade I, n = 27; II, n = 132; IlIa, n = 290; IIIb, n = 4; IVa, n = 21; IVb, n = 1; and V, n = 9). The trajectory was categorized into 3 patterns: mild (n = 209), moderate (n = 235), and severe (n = 40) morbidity courses. The 90-day mortality rate significantly differed among the courses: 0%, 0.9%, and 17.5%, respectively (P<0.001). The cutoff values of the CCI on postoperative days 1, 4, and 7 for predicting a severe morbidity course were 15.0, 28.5, and 40.6 with areas under the curves of 0.780, 0.924, and 0.984, respectively. CONCLUSIONS: The CCI could depict the chronological increase in the overall morbidity burden, categorized into 3 patterns. Early CCI potentially predicted sequential progression to serious outcomes.

Efficacy of Extended Modification in Left Hemihepatectomy for Advanced Perihilar Cholangiocarcinoma: Comparison Between H12345'8'-B-MHV and H1234-B.

OBJECTIVE: The aim of this study was to verify the prognostic impact of the tumor exposure at the liver transection margin (LTM) in left-sided perihilar cholangiocarcinoma and the impact of middle hepatic vein (MHV) resection on this exposure. BACKGROUND: In perihilar cholangiocarcinoma, tumors are unexpectedly exposed at the LTM during left hemihepatectomy (LH). METHODS: Patients who underwent LH for perihilar cholangiocarcinoma during 2002 to 2018 were retrospectively evaluated. LH was classified into conventional and extended types, which preserved and resected the MHVs, respectively. Positive LTM was defined as the involvement of invasive carcinoma at the liver transection plane and/or the adjacent Glissonean pedicle exposed. The clinicopathologic features and survival outcomes were compared between procedures. RESULTS: Among 236 patients, conventional and extended LHs were performed in 198 and 38 patients, respectively. The LTM was positive in 31 (13%) patients, with an incidence of 14% versus 8% ( P = 0.432) and 24% versus 0% in advanced tumors ( P = 0.011). Tumor size ≥ 18 mm ( P = 0.041), portal vein invasion ( P = 0.009), and conventional LH ( P = 0.028) independently predicted positive LTM. In patients with negative LTM, the survival was comparable between the two groups: 60.4% versus 59.2% at 3 years ( P = 0.206), which surpassed 17.7% for those with positive LTM in the conventional group ( P < 0.001). Multivariable analysis demonstrated that LTM status was an independent prognostic factor ( P = 0.009) along with ductal margin status ( P = 0.030). CONCLUSIONS: The LTM status is an important prognostic factor in perihilar cholangiocarcinoma. Extended LH reduced the risk of tumor exposure at the LTM with a subsequent improvement in the survival, particularly in advanced tumors.

The Goal of Intraoperative Blood Loss in Major Hepatobiliary Resection for Perihilar Cholangiocarcinoma: Saving Patients From a Heavy Complication Burden.

OBJECTIVE: To determine the goal of intraoperative blood loss in hepatectomy for perihilar cholangiocarcinoma. BACKGROUND: Although massive bleeding can negatively affect the postoperative course, the target value of intraoperative bleeding to reduce its adverse impact is unknown. METHODS: Patients who underwent major hepatectomy for perihilar cholangiocarcinoma between 2010 and 2019 were included. Intraoperative blood loss was adjusted for body weight [adjusted blood loss (aBL)], and the overall postoperative complications were evaluated by the comprehensive complication index (CCI). The impact of aBL on CCI was assessed by the restricted cubic spline regression. RESULTS: A total of 425 patients were included. The median aBL was 17.8 (interquartile range, 11.8-26.3) mL/kg, and the CCI was 40.6 (33.7-49.5). Sixty-three (14.8%) patients had an aBL<10 mL/kg, nearly half (45.4%) of the patients were in the range of 10 ≤aBL<20 mL/kg, and 37 (8.7%) patients had an aBL >40 mL/kg. The spline regression analysis showed a nonlinear incremental association between aBL and CCI; CCI remained flat with an aBL under 10 mL/kg; increased significantly with an aBL ranging from 10 to 20 mL/kg; grew gradually with an aBL over 20 mL/kg. These inflection points of ~10 and 20 mL/kg were almost consistent with the cutoff values identified by the recursive partitioning technique. After adjusting for other risk factors for the postoperative course, the spline regression identified a similar model. CONCLUSIONS: aBL had a nonlinear aggravating effect on CCI after hepatectomy for perihilar cholangiocarcinoma. The primary goal of aBL should be <10 mL/kg to minimize CCI.

Which modality is better to diagnose high-grade transformation in retroperitoneal liposarcoma? Comparison of computed tomography, positron emission tomography, and magnetic resonance imaging.

BACKGROUND: Survival in patients with retroperitoneal liposarcoma (RPLS) depends on the surgical management of the dedifferentiated foci. The present study investigated the diagnostic yield of contrast-enhanced CT, 18F-fluorodeoxyglucose positron emission tomography (PET), and diffusion-weighted MRI in terms of dedifferentiated foci within the RPLS. METHODS: Patients treated with primary or recurrent RPLS who underwent the above imaging between January 2010 and December 2021 were retrospectively reviewed. The diagnostic accuracy of the three modalities for histologic subtype of dedifferentiated liposarcoma (DDLS) and French Federation of Cancer Center (FNCLCC) grade 2/3 were compared using receiver operating characteristic curves and areas under the curves (AUCs). RESULTS: The cohort involved 32 patients with 53 tumors; 30 of which exhibited DDLS and 31 of which did FNCLCC grades 2/3. The optimal thresholds for predicting DDLS were mean CT value of 31 Hounsfield Unit (HU) (AUC = 0.880, 95% CI 0.775-0.984; p < 0.001), maximum standardized uptake value (SUVmax) of 2.9 (AUC = 0.865 95% CI 0.792-0.980; p < 0.001), while MRI failed to differentiate DDLS. The cutoff values for distinguishing FNCLCC grades 1 and 2/3 were a mean CT value of 24 HU (AUC = 0.858, 95% CI 0.731-0.985; p < 0.001) and SUVmax of 2.9 (AUC = 0.885, 95% CI 0.792-0.978; p < 0.001). MRI had no sufficient power to separate these grades. CONCLUSIONS: Contrast-enhanced CT and PET were useful for predicting DDLS and FNCLCC grade 2/3, while MRI was inferior to these two modalities.

Clinical value of fluorescent cholangiography for the infraportal type of right posterior bile duct.

BACKGROUND: The infraportal type of the right posterior bile duct (infraportal RPBD) is a well-known anatomical variation that increases the potential risk of intraoperative biliary injury. The aim of this study is to clarify the clinical value of fluorescent cholangiography during single-incision laparoscopic cholecystectomy (SILC) for patients with infraportal RPBD. MATERIAL AND METHODS: Our procedure for SILC utilized the SILS-Port, and another 5-mm forceps was inserted via an umbilical incision. A laparoscopic fluorescence imaging system developed by Karl Storz Endoskope was utilized for fluorescent cholangiography. Between July 2010 and March 2022, 41 patients with infraportal RPBD underwent SILC. We conducted retrospective reviews of patient data, focusing on the clinical value of fluorescent cholangiography. RESULTS: Thirty-one patients underwent fluorescent cholangiography during SILC, but the remaining ten did not. Only one patient who did not undergo fluorescent cholangiography developed an intraoperative biliary injury. The detectability of infraportal RPBD before and during the dissection of Calot's triangle was 16.1% and 45.2%, respectively. These visible infraportal RPBDs were characterized as connections to the common bile duct. The confluence pattern of infraportal RPBD significantly influenced its detectability during the dissection of Calot's triangle (p < 0.001). CONCLUSIONS: The application of fluorescent cholangiography can lead to safe SILC, even for patients with infraportal RPBD. Its benefit is emphasized when infraportal RPBD is connected to the common bile duct.

Combined Vascular Resection for Locally Advanced Perihilar Cholangiocarcinoma.

OBJECTIVE: To evaluate the efficacy and safety of combined vascular resection (VR) in advanced perihilar cholangiocarcinoma (PHC). SUMMARY OF BACKGROUND DATA: Hepatectomy combined with portal vein resection (PVR) and/or hepatic artery resection (HAR) is technically demanding but an option only for tumor eradication against PHC involving the hilar hepatic inflow vessels; however, its efficacy and safety have not been well evaluated. METHODS: Patients diagnosed with PHC during 2001-2018 were included. Patients who underwent resection were divided according to combined VR. Patients undergoing VR were subdivided according to type of VR. Postoperative outcomes and OS were compared between patient groups. RESULTS: Among the 1055 consecutive patients, 787 (75%) underwent resection (without VR: n = 484, PVR: n = 157, HAR: n = 146). The incidences of postoperative complications and mortality were 49% (without VR vs with VR, 48% vs 50%; P= 0.715) and 2.1% (without VR vs with VR, 1.2% vs 3.6%; P= 0.040), respectively. The OS of patients who underwent resection with VR (median, 30 months) was shorter than that of those who underwent resection without VR (median, 61 months; P < 0.0001); however, it was longer than that of those who did not undergo resection (median, 10 months; P < 0.0001). OS was not significantly different between those who underwent PVR and those who underwent HAR (median, 29 months vs 34 months; P = 0.517). CONCLUSION: VR salvages a large number of patients from having locally advanced PHC that is otherwise unresectable and is recommended if the hilar hepatic inflow vessels are reconstructable, providing acceptable surgical outcomes and substantial survival benefits.

Mild Prognostic Impact of Postoperative Complications on Long-term Survival of Perihilar Cholangiocarcinoma.

OBJECTIVE: To evaluate the impact of complications on long-term survival in patients with perihilar cholangiocarcinoma. BACKGROUND: Surgical resection for perihilar cholangiocarcinoma is vulnerable to postoperative complications. The prognostic impact of complications in patients with this disease is unknown. METHODS: The medical records of patients who underwent curative-intent hepatectomy for perihilar cholangiocarcinoma between 2010 and 2017 were reviewed retrospectively. The comprehensive complication index (CCI) was calculated based on all postoperative complications, which were graded by the Clavien-Dindo classification (CDC). Patients were divided into high and low CCI groups by the median score, and survival was compared between the 2 groups. RESULTS: Excluding 8 patients who died in hospital, 369 patients were analyzed. The CDC grade was I in 20 (5.4%), II in 108 (29.3%), III in 224 (60.7%), and IV in 17 (4.6%) patients. The CCI increased with increasing CDC grade; the median was 42.9 (range, 15.0-98.9). Overall survival differed significantly between the high (n = 187) and low (n = 182) CCI groups (41.2% vs 47.9% at 5 years; P = 0.041). However, multivariable analyses demonstrated that traditional clinicopathological factors were independent predictors of survival and that the dichotomized CCI was not. In addition, the CCI score as a continuous variable was not an independent prognostic factor for overall survival in the multivariable analyses (hazard ratio per 1 CCI score: 1.00, 95% confidence interval: 0.99-1.01, P = 0.775). CONCLUSIONS: Cumulative postoperative complications after resection of perihilar cholangiocarcinoma only moderately deteriorate long-term survival, and should not be an argument to deny surgery in this high-risk population.

Impact of Perioperative Steroid Administration in Patients Undergoing Major Hepatectomy with Extrahepatic Bile Duct Resection: A Randomized Controlled Trial.

BACKGROUND: To date, five randomized controlled trials have assessed the clinical benefit of perioperative steroid administration in hepatectomy; however, all of these studies involved a substantial number of 'minor' hepatectomies. The benefit of steroid administration for patients undergoing 'complex' hepatectomy, such as major hepatectomy with extrahepatic bile duct resection, is still unclear. This study aimed to evaluate the clinical benefit of perioperative steroid administration for complex major hepatectomy. METHODS: Patients with suspected hilar malignancy scheduled to undergo major hepatectomy with extrahepatic bile duct resection were randomized into either the control or steroid groups. The steroid group received hydrocortisone 500 mg immediately before hepatic pedicle clamping, followed by hydrocortisone 300 mg on postoperative day (POD) 1, 200 mg on POD 2, and 100 mg on POD 3. The control group received only physiologic saline. The primary endpoint was the incidence of postoperative liver failure. RESULTS: A total of 94 patients were randomized to either the control (n = 46) or steroid (n = 48) groups. The two groups had similar baseline characteristics; however, there were no significant differences between the groups in the incidence of grade B/C postoperative liver failure (control group, n = 8, 17%; steroid group, n = 4, 8%; p = 0.188) and other complications. Serum bilirubin levels on PODs 2 and 3 were significantly lower in the steroid group than those in the control group; however, these median values were within normal limits in both groups. CONCLUSION: Perioperative steroid administration did not reduce the risk of postoperative complications, including liver failure following major hepatectomy with extrahepatic bile duct resection.

New method for the assessment of perineural invasion from perihilar cholangiocarcinoma.

PURPOSE: Perineural invasion (PN) is often found in perihilar cholangiocarcinoma. New procedure was developed to assess PN around the right hepatic artery (RHA) using dual-energy computed tomography (DECT). METHODS: Thirty patients with perihilar cholangiocarcinoma who underwent DECT before biliary drainage were retrospectively reviewed. Mask images, i.e., the periarterial layer (PAL) around the RHA and superior mesenteric artery (SMA), were made from late arterial phase DECT. The mean CT number of the PAL was measured. RESULTS: Twenty patients with PN around the RHA were classified into the PN (+) group. The remaining 10 patients without PN and other 26 patients with other diseases that are never accompanied with PN were classified into the PN (-) group. The PAL ratio (the CT number of the PAL around the RHA relative to that around the SMA) was calculated. Both the mean CT number of the PAL around the RHA and the PAL ratio were significantly higher in the PN (+) group than in the PN (-) group. According to an ROC analysis, the predictive ability of the PAL ratio was superior. Using the cutoff value of the PAL ratio 1.009, a diagnosis of PN around the RHA was made with approximately 75% accuracy. CONCLUSIONS: Assessment with CT number of the PAL reconstructed from DECT images is an easy and objective method to diagnose PN.

Impact of the preoperative body composition indexes on intraoperative blood loss in patients undergoing pancreatoduodenectomy.

PURPOSES: This study sought to identify any significant predictors of blood loss during pancreatoduodenectomy (PD) among preoperative variables, including the body composition indexes. METHODS: The preoperative data of patients undergoing PD were retrospectively reviewed. The objective variable was the percentage of blood loss during PD to the estimated circulating blood volume (proportional blood loss: PBL). The circulating blood volume was estimated using Nadler's formula. The total psoas area, average Hounsfield units of psoas area (psoas muscle density: PMD), and visceral to subcutaneous adipose tissue area ratio (VSR) were measured at the third vertebra using preoperative plain computed tomography images. A univariate analysis and multiple linear regression analysis for PBL were conducted using the preoperative variables. RESULTS: A total of 415 patients were analyzed. The median PBL was 24.5%. The PMD (coefficient - 0.267; 95% CI - 0.518, - 0.015), VSR (coefficient 2.719; 95% CI 0.238, 5.201), serum albumin level (coefficient - 8.458; 95% CI - 13.02, - 3.898), neoadjuvant therapy (coefficient 9.605; 95% CI 1.722, 17.49), and prothrombin time-international normalized ratio (PT-INR, coefficient 38.63; 95% CI 10.94, 66.31) were independently associated with PBL. CONCLUSIONS: The preoperative PMD, VSR, serum albumin level, neoadjuvant therapy, and PT-INR independently affected PBL. These factors could therefore be potential targets to reduce blood loss during PD.

A clinicopathological reappraisal of intraductal papillary neoplasm of the bile duct (IPNB): a continuous spectrum with papillary cholangiocarcinoma in 181 curatively resected cases.

BACKGROUND: Intraductal papillary neoplasm of the bile-duct (IPNB) has recently been further subclassified into "so-called IPNBs" (Type-1) and "narrow-sense papillary cholangiocarcinomas" (Type-2), but their differential diagnosis is challenging. This study aimed to reevaluate Type-1 and Type-2 IPNBs. METHODS: Consecutive patients who underwent papillary bile-duct tumor resection were included. Using six pathological features (location, mucin secretion, histological architecture, histological type, presence of a low/intermediate-dysplasia component, and proportion of the invasive component), all papillary tumors were scored. Tumors scoring 5-6 were classified as Type-1, 0-1 as Type-2, and 2-4 as Type-Unclassifiable. RESULTS: The 181 papillary bile-duct tumor patients were divided into three groups, consisting of 12 Type-1, 46 Type-2, and 123 Type-Unclassifiable-gray-zone lesions between Type-1 and Type-2 that constituted the largest proportion of papillary tumors. Type-1 tumors were pathologically the least advanced, while the other types showed gradual advancement. The 5-year survival rate was better for patients with Type-1 tumors than for those with Type-Unclassifiable or Type-2 tumors. CONCLUSION: The scoring system worked well to delineate a continuous spectrum of pathologic features ranging from Type-1, through Type-Unclassifiable, to Type-2, the latter two being challenging to differentially diagnose. Type-1 is regarded as an early neoplasm of Type-Unclassifiable and Type-2.

Study of the Portal Branches Arising from the Cranial Part of the Umbilical Portion of the Left Portal Vein: Implications for Anatomic Right Hepatic Trisectionectomy.

BACKGROUND: In "anatomic" right hepatic trisectionectomy for advanced perihilar cholangiocarcinoma, the left hepatic duct is divided at the left side of the umbilical portion (UP) of the left portal vein (LPV). For this reason, the left hepatic duct is completely detached from the UP after all division of the portal branches arising cranially from the UP. However, little is known about these thin portal branches. METHODS: Using 3D imaging processing software, we examined the portal branches arising cranially from the UP of the LPV in 100 patients who underwent multidetector row computed tomography (MDCT). Special attention was paid to the portal branch running to the left lateral sector, designated as the left cranio-lateral branch. RESULTS: The left cranio-lateral portal branch number was 0 in 57 patients, 1 in 32 patients, and 2 in 11 patients. Thus, 54 left cranio-lateral branches were identified, arising from near the cul-de-sac of the UP, from near the elbow of the LPV, or from the UP trunk. The median volume of the territory supplied by the left cranio-lateral portal branch was 21 mL (range, 5-47 mL), and the median ratio to the left lateral sector was 11.8% (range, 1.7-25.0%). CONCLUSION: Approximately 40% of patients had the left cranio-lateral portal branches arising cranially from the UP and running to the left lateral sector. When planning anatomic right hepatic trisectionectomy, the presence or absence of this branch should be checked by using 3D imaging with MDCT.

Study on the Segmentation of the Right Posterior Sector of the Liver.

BACKGROUND: The border between segments VI and VII of the right posterior sector of the liver is controversial owing to lack of anatomical landmarks. This study aimed to examine the segmentation of the right posterior sector. METHODS: Using three-dimensional software, ramification type of the right posterior portal vein (RPPV) was analysed in 100 patients. RESULTS: A bow-shaped anatomy, in which the RPPV exhibits a downward convex bow shape with several ramifications, was found in 50 patients. A bifurcation anatomy, in which the RPPV bifurcates into the cranial and caudal branches, was observed in 45 patients. In the bow-shaped anatomy, setting the segmentation was difficult due to lack of definite landmarks; thus, the downward portal branches were determined as segment VI branches, while horizontal and upward branches were determined as segment VII branches. In the bow-shaped anatomy, the incidence of full exposure of a thick branch of the right hepatic vein on virtual transection surface was 60.0%, while in the bifurcation anatomy, it was only 11.1%. No relations were observed between RPPV anatomy and main PV/right hepatic vein anatomy. The volumes of segments VI and VII were equal in both the bow-shaped and bifurcation anatomy. CONCLUSIONS: The bow-shaped and bifurcation types are commonly observed in RPPV anatomy. In the bifurcation anatomy, the right posterior sector is divided into segments VI and VII. In the bow-shaped anatomy, setting the segmentation was difficult, thus it may be compelled to be arbitrarily determined.

The influence of the preoperative thickness of the abdominal cavity on the gastrojejunal anatomic position and delayed gastric emptying after pancreatoduodenectomy.

BACKGROUND: We aimed to investigate the hypothesis that preoperative thickness of the abdominal cavity influenced on the gastrojejunostomy position and the incidence of delayed gastric emptying (DGE) after pancreatoduodenectomy. METHODS: Between January 2009 and December 2018, consecutive patients who underwent subtotal stomach-preserving pancreatoduodenectomy were retrospectively reviewed. Thickness of the abdominal cavity at the level of the celiac axis (TACC) and umbilicus (TACU) were measured using computed tomography before surgery. The ventral deviation of the gastrojejunostomy was evaluated as the sagittal fundus anastomotic angle (SFAA) using sagittal computed tomography images taken after surgery. RESULTS: A total of 281 patients were included. Of these, clinically relevant DGE (CR-DGE) was observed in 47 patients. TACC was significantly correlated with SFAA (R = 0.53, P < 0.001). Both TACC and SFAA were significantly greater in patients with CR-DGE compared to those without CR-DGE. In contrast, TACU was not associated with SFAA and the incidence of CR-DGE. Multivariate analysis revealed that TACC >110 mm (odds ratio, 3.07; p = 0.002) and pancreatic fistula (odds ratio, 2.71; p = 0.013) were identified as independent risk factors for CR-DGE. CONCLUSION: Thickness of the upper abdominal cavity had a significant influence on gastrojejunal anatomic position and the development of CR-DGE after pancreatoduodenectomy.

Cholangiographic Tumor Classification for Simple Patient Selection Prior to Hepatopancreatoduodenectomy for Cholangiocarcinoma.

BACKGROUND: Hepatopancreatoduodenectomy (HPD) is employed for patients with laterally advanced cholangiocarcinoma. However, the survival benefit of this extended approach remains controversial. The aim of this study is to identify a tumor feature benefiting from HPD from the standpoint of long-term survival. PATIENTS AND METHODS: Patients with cholangiocarcinoma who underwent HPD with curative intent between 2001 and 2017 were retrospectively analyzed. Tumors were radiologically classified by preoperative cholangiogram. Diffuse type was defined as significant tumor/stricture located from the hilar to intrapancreatic duct; localized type was defined as tumor otherwise. Univariable and multivariable analyses were performed to identify prognostic indicators. RESULTS: Of 100 study patients, 28 (28%) patients had diffuse tumor type, while the remaining 72 (72%) patients had localized tumors. The former group showed significantly longer lateral length (43 versus 22 mm, P < 0.001) and more frequent pancreatic invasion (50% versus 32%, P = 0.110), advanced T classification (64% versus 49%, P = 0.185), and nodal metastasis (57% versus 47%, P = 0.504), compared with the latter group. The survival for patients with diffuse tumor type was significantly worse than that for patients with localized tumor type, with 5-year survival rates of 59.0% versus 26.3%, respectively (P = 0.003). Multivariable analysis identified four independent factors deteriorating long-term survival: cholangiographic diffuse tumor (P = 0.021), higher age (P = 0.020), percutaneous biliary drainage (P = 0.007), and portal vein resection (P = 0.007). CONCLUSIONS: Presurgical cholangiographic classification, diffuse or localized type, is a tumor-related factor closely associated with survival probability; therefore, it may be a useful feature for patient selection prior to HPD for cholangiocarcinoma.

Is constant negative pressure for external drainage of the main pancreatic duct useful in preventing pancreatic fistula following pancreatoduodenectomy?

BACKGROUND: This study sought to investigate the utility of constant negative pressure for external drainage of the main pancreatic duct in preventing postoperative pancreatic fistula (POPF) after pancreatoduodenectomy. METHODS: Only patients with soft pancreas were included. In the former period (July 2013 to May 2015), gravity dependent drainage was applied (gravity dependent drainage group), and in the latter period (June 2015 to November 2016), constant negative pressure drainage (negative pressure drainage group) was applied to the main pancreatic duct stent. RESULTS: There were 37 patients in the gravity dependent drainage group and 39 patients in the negative pressure drainage group. Clinically relevant POPF occurred in 21 patients (56.8%) in the gravity dependent drainage group and 13 patients (33.3%) in the negative pressure drainage group (p = 0.040). The incidence rate of major complications (Clavien-Dindo grade > III) was significantly lower in the negative pressure drainage group (13.2%) compared to the gravity dependent drainage group (48.7%) (p = 0.001). In-hospital stay was also significantly shorter in the negative pressure drainage group compared to the gravity dependent drainage group (median 25 vs. 33 days, p = 0.024). Multivariate analysis demonstrated that the gravity dependent drainage was one of the independent risk factors for the incidence of POPF (odds ratio, 3.33; p = 0.032). CONCLUSIONS: In patients with soft pancreas, the incidence rate of clinically relevant POPF may be reduced by applying constant negative pressure to the pancreatic duct stent. It also has a potential to reduce overall incidence of major complications and shorten in-hospital stay after pancreatoduodenectomy.

Discrepancy between volume and functional recovery in early phase liver regeneration following extended hepatectomy with extrahepatic bile duct resection.

AIM: To elucidate the clinical factors having an impact on liver regeneration rate following preoperative portal vein embolization (PVE) and subsequent extended hepatectomy. The correlation between liver volume and functional recovery after extended hepatectomy was also investigated. METHODS: Records of patients who underwent extended hepatectomy with extrahepatic bile duct resection following PVE for perihilar cholangiocarcinoma were reviewed retrospectively with attention to liver regeneration. All patients underwent computed tomography before PVE, after PVE (immediately before surgery), and on postoperative day (POD) 7. The kinetic growth rate (KGR) was calculated as the percent increase in liver volume relative to the future liver remnant volume per day after PVE (KGRPVE ) and after POD 7 (KGRPOD7 ) using the computed tomography images before PVE, after PVE, and on POD 7. RESULTS: In the 289 study patients, the median of KGRPVE was 1.35%/day whereas that of KGRPOD7 was 5.56%/day. The extent of liver resection had the greatest impact on both KGRPVE and KGRPOD7 and the impacts of other factors were less. There was a significant negative correlation between KGRPVE and KGRPOD7 (P = 0.002). No correlations were observed between KGRPVE or KGRPOD7 and serum total bilirubin and prothrombin time - international normalized ratio on POD 7, nor in the incidence of liver failure after surgery. CONCLUSIONS: Early phase liver regeneration after extended hepatectomy was largely influenced by the extent of liver resection and showed no correlation with the indices of liver failure. There was a discrepancy between volume and functional recovery in early phase liver regeneration.