Factors Affecting Nonfunctioning Small Pancreatic Neuroendocrine Neoplasms and Proposed New Treatment Strategies.

BACKGROUND & AIMS: Despite previously reported treatment strategies for nonfunctioning small (≤20 mm) pancreatic neuroendocrine neoplasms (pNENs), uncertainties persist. We aimed to evaluate the surgically resected cases of nonfunctioning small pNENs (NF-spNENs) in a large Japanese cohort to elucidate an optimal treatment strategy for NF-spNENs. METHODS: In this Japanese multicenter study, data were retrospectively collected from patients who underwent pancreatectomy between January 1996 and December 2019, were pathologically diagnosed with pNEN, and were treated according to the World Health Organization 2019 classification. Overall, 1490 patients met the eligibility criteria, and 1014 were included in the analysis cohort. RESULTS: In the analysis cohort, 606 patients (59.8%) had NF-spNENs, with 82% classified as grade 1 (NET-G1) and 18% as grade 2 (NET-G2) or higher. The incidence of lymph node metastasis (N1) by grade was significantly higher in NET-G2 (G1: 3.1% vs G2: 15.0%). Independent factors contributing to N1 were NET-G2 or higher and tumor diameter ≥15 mm. The predictive ability of tumor size for N1 was high. Independent factors contributing to recurrence included multiple lesions, NET-G2 or higher, tumor diameter ≥15 mm, and N1. However, the independent factor contributing to survival was tumor grade (NET-G2 or higher). The appropriate timing for surgical resection of NET-G1 and NET-G2 or higher was when tumors were >20 and >10 mm, respectively. For neoplasms with unknown preoperative grades, tumor size >15 mm was considered appropriate. CONCLUSIONS: NF-spNENs are heterogeneous with varying levels of malignancy. Therefore, treatment strategies based on tumor size alone can be unreliable; personalized treatment strategies that consider tumor grading are preferable.

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.

Intraductal papillary neoplasms of the bile ducts: a comparative study of a rare disease in Europe and Nagoya, Japan.

BACKGROUND: Intraductal papillary neoplasm of the bile ducts (IPNB) is a rare disease in Western countries. The aim of this study was to compare tumor characteristics, management strategies, and outcomes between Western and Eastern patients who underwent surgical resection for IPNB. METHODS: A multi-institutional retrospective series of patients with IPNB undergoing surgery between January 2010 and December 2020 was gathered under the auspices of the European-African Hepato-Pancreato-Biliary Association (E-AHPBA), and at Nagoya University Hospital, Japan. RESULTS: A total of 85 patients (51% male; median age 66 years) from 28 E-AHPBA centers were compared to 91 patients (64% male; median age 71 years) from Nagoya. Patients in Europe had more multiple lesions (23% vs 2%, P < .001), less invasive carcinoma (42% vs 85%, P < .001), and more intrahepatic tumors (52% vs 24%, P < .001) than in Nagoya. Patients in Europe experienced less 90-day grade >3 Clavien-Dindo complications (33% vs 68%, P < .001), but higher 90-day mortality rate (7.0% vs 0%, P = .03). R0 resections (81% vs 82%) were similar. Overall survival, excluding 90-day postoperative deaths, was similar in both regions. DISCUSSION: Despite performing more extensive resections, the low perioperative mortality rate observed in Nagoya was probably influenced by a combination of patient-, tumor-, and surgery-related factors.

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.

Liver remnant volume to body weight ratio of 0.65% as a lower limit in right hepatic trisectionectomy with bile duct resection.

BACKGROUND: Previous studies have suggested the utility of an indocyanine green plasma clearance rate of the future liver remnant (FLR) (ICGK-F) ≥0.05 in hepatobiliary resection to reduce the surgical risk. The present study aimed to verify whether future liver remnant size rather than ICGK-F matters in extended hepatobiliary resection. METHODS: Between 2004 and 2021, patients who underwent right hepatic trisectionectomy with bile duct resection were included. The effect of the FLR volume-to-body weight ratio (FLR/BW) and ICGK-F on posthepatectomy liver failure was evaluated along with other parameters. RESULTS: Among 91 study patients, the median ICGK-F, FLR, and FLR/BW were 0.057 (range, 0.027-0.099), 392 mL (145-705), and 0.78% (0.40-1.37), respectively. Posthepatectomy liver failure occurred in 23 patients. The incidence was 10 (40%) in 25 patients with an ICGK-F <0.05 and 12 (18%) in 65 patients with an ICGK-F ≥0.05 (P = .053); 13 (52%) in 25 patients with a FLR/BW <0.65% and 10 (15%) in 66 patients with a FLR/BW ≥0.65% (P = .001). Multivariate analysis showed that a FLR/BW <0.65% (odds ratio, 11.7; P = .005), age ≥65 years (odds ratio, 31.7; P < .001), and blood loss ≥25 mL/kg (odds ratio, 22.1; P = .004) were independent predictors of posthepatectomy liver failure, but ICGK-F <0.05 was not (P = .499). According to the meeting number of 3 factors, posthepatectomy liver failure incidence was 0 of 22 (0%) in patients with 0 factors, 6 of 43 (14%) in patients with 1, and 17 of 26 (65%) in patients with 2 or 3 (P < .001). CONCLUSION: A FLR/BW ≥0.65% may serve as a volumetric basis to reduce posthepatectomy liver failure after extended hepatobiliary resection.

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.

Standard versus delayed initiation of S-1 adjuvant chemotherapy after surgery for pancreatic cancer: a secondary analysis of a nationwide cohort by the Japan Pancreas Society.

BACKGROUND: Based on the Japan Adjuvant Study Group of Pancreatic Cancer-01 results, S-1 adjuvant chemotherapy has been the standard in resected pancreatic ductal adenocarcinoma (PDAC) patients in Japan and elsewhere, initiated within 10 weeks after surgery. To assess the clinical impact of this timing, we conducted a secondary analysis of a nationwide survey by the Japan Pancreas Society. METHODS: A total of 3361 patients were divided into two groups: 2681 (79.8%) initiating the therapy within 10 weeks after surgery (standard) and 680 (20.2%) after 10 weeks (delayed). We compared recurrence-free survival (RFS) and overall survival (OS) using the log-rank test and Cox proportional hazards model with conditional landmark analysis between the groups. Results were verified by adjustment with inverse-probability-of-treatment weighting (IPTW) analysis. RESULTS: The median timing of S-1 adjuvant chemotherapy initiation was 50 days (interquartile range: 38-66). In the standard group, 5-year RFS and OS rates were 32.3-48.7%, respectively, compared with 25.0-38.7% in the delayed group. Hazard ratios (HRs) and 95% confidence intervals were 0.84 (0.76-0.93) for RFS (p < 0.001) and 0.77 (0.69-0.87) for OS (p < 0.001). The IPTW analysis yielded 5-year RFS rates of 32.1% and 25.3% in the standard versus delayed group, respectively [HR = 0.86 (0.77-0.96), p < 0.001] and 5-year OS rates of 48.3% and 39.8%, respectively [HR = 0.81 (0.71-0.92), p < 0.001]. CONCLUSIONS: Initiation of S-1 adjuvant chemotherapy in resected PDAC patients within 10 weeks after surgery may offer survival benefit over later initiation.

Two-step arterial reconstruction technique for en bloc resection of a large retroperitoneal liposarcoma involving the common iliac artery.

Retroperitoneal liposarcoma (RPLS) is a rare but challenging neoplasm, which is frequently associated with iliac vessel invasion. We describe how we used a two-step arterial reconstruction technique to perform en bloc resection of a large RPLS involving the iliac arteries in three patients. A temporal long in situ graft bypass was established using a prosthetic vascular graft during dissection of the tumor. This bypass provided an unobscured surgical field, while maintaining blood flow in the lower limb during the operation. After removal of the tumor and washing out the abdominal cavity, the new prosthetic vascular graft of a suitable length was placed. No graft-related complications, including vascular graft infection or graft occlusion, occurred during the follow-up period. This novel technique appears to provide a safe and effective way to remove large RPLSs involving the retroperitoneal major vessels.

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.

Impact of skeletal muscle mass on the prognosis of patients undergoing neoadjuvant chemotherapy for resectable or borderline resectable pancreatic cancer.

BACKGROUND: Neoadjuvant chemotherapy is a common therapeutic procedure for patients with pancreatic cancer. This study aimed to investigate the association between the total psoas area (TPA) and prognosis in patients undergoing neoadjuvant chemotherapy for resectable or borderline resectable pancreatic cancer. STUDY DESIGN: This retrospective study included patients who underwent neoadjuvant chemotherapy for pancreatic cancer. TPA was measured at the level of the L3 vertebra using computed tomography. The patients were divided into low-TPA and normal-TPA groups. These dichotomizations were separately performed in patients with resectable and those with borderline resectable pancreatic cancer. RESULTS: In total, 44 patients had resectable pancreatic cancer and 71 patients had borderline resectable pancreatic cancer. Overall survival among patients with resectable pancreatic cancer did not differ between the normal- and low-TPA groups (median, 19.8 vs. 21.8 months, p = 0.447), whereas among patients with borderline resectable pancreatic cancer, the low-TPA group had shorter overall survival than the normal-TPA group (median, 21.8 vs. 32.9 months, p = 0.006). Among patients with borderline resectable pancreatic cancer, the low-TPA group was predictive of poor overall survival (adjusted hazard ratio, 2.57, p = 0.037). CONCLUSION: Low TPA is a risk factor of poor survival in patients undergoing neoadjuvant chemotherapy for borderline resectable pancreatic cancer. TPA evaluation could potentially suggest the treatment strategy in this disease.

Cyclodextrin Conjugated α-Bisabolol Suppresses FAK Phosphorylation and Induces Apoptosis in Pancreatic Cancer.

BACKGROUND/AIM: α-Bisabolol is an essential oil component extracted from plants, such as chamomile. We have previously reported that α-bisabolol suppressed proliferation, invasion, and motility of pancreas cancer. Cyclodextrin improved the solubility of α-bisabolol, therefore it enabled to administer intravenously. The aim of this study was to clarify the effect of cyclodextrin conjugated α-bisabolol (CD-BSB) and the signals pathways associated with α-bisabolol for pancreatic cancer. MATERIALS AND METHODS: Human pancreatic cancer cell lines were treated with or without CD-BSB. Cytomorphology and apoptosis were assessed in these treated groups. In addition, several phosphorylated proteins were analyzed to clarify the signal pathway concerning CD-BSB. In subcutaneous xenograft model, tumor volume and Ki-67 expression were evaluated among Control (untreated), CD-BSB, or Gemcitabine (GEM). RESULTS: CD-BSB significantly changed cytomorphology and induced apoptosis in pancreatic cancer cells. CD-BSB suppressed phosphorylation of focal adhesion kinase (FAK). In addition, pFAK 397 was inhibited by CD-BSB in a concentration-dependent manner in cancer cells. In the subcutaneous xenograft models, the tumor volume in the CD-BSB groups was lower than Control groups. Ki67-positive cells in CD-BSB treated group were lower than the GEM-treated groups. CONCLUSION: We clarified the efficiency of CD-BSB in xenograft tumor using intravenous administration. α-Bisabolol suppresses phosphorylation of FAK 397 and impairs cytoskeletal polymerization in a pancreatic cancer cell line. Further investigations are required to reveal the precise mechanisms of the antitumor effects of solubilized α-bisabolol to facilitate its clinical application. Our data indicate that solubilized α-bisabolol has therapeutic potential and could improve the prognosis of cancer patients.

Antitumor Effects of Deep Ultraviolet Irradiation for Pancreatic Cancer.

BACKGROUND/AIM: Deep ultraviolet (DUV) light spans within the 250 nm to 350 nm invisible wavelength range. Although it strongly damages various cells, the efficacy of DUV irradiation on pancreatic cancer cells has never been clarified. The purpose of this study was to reveal the antitumor effects of DUV irradiation on pancreatic cancer cells. MATERIALS AND METHODS: Human pancreatic cancer cell lines were eradicated with DUV or ultraviolet A (UVA) for 5 s. Several angiogenesis-related proteins were studied in cancer cells after DUV irradiation using a protein antibody array. A subcutaneous xenograft model was established by inoculation of pancreatic cancer cells into mice. Tumors in this model were irradiated with DUV or UVA once or twice for two weeks. Tumor volumes in these groups (DUV×1: one irradiation, DUV×2: two irradiations, and untreated) were analyzed one week after the second irradiation. RESULTS: DUV irradiation significantly changed the cytomorphology of pancreatic cancer cells. In addition, DUV irradiation induced apoptosis on pancreatic cancer cells more strongly than UVA irradiation and no irradiation. Interestingly, lower expression of thrombospondin 1 (TSP1) and tissue inhibitor of metalloproteinase 1 (TIMP1) was identified after DUV treatment. The tumor volume in the DUV-treated groups (DUV×1 and DUV×2) was smaller than that in the untreated group. CONCLUSION: Further investigations are required to reveal the precise mechanisms of the antitumor effects of DUV irradiation and to facilitate its clinical application as a new therapy for pancreatic cancer. Overall, DUV irradiation can be potentially used as a therapeutic option of pancreatic malignancy.

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.

Is a specific T classification needed for extrahepatic intraductal papillary neoplasm of the bile duct (IPNB) type 2 associated with invasive carcinoma?

BACKGROUND: The necessity of a specific T classification for extrahepatic intraductal papillary neoplasm of the bile duct (IPNB) type 2, one of the precursors of cholangiocarcinoma (CC), remains unclear. METHODS: Patients who underwent resection for extrahepatic biliary tumors were reviewed. Relapse-free survival (RFS) was compared between IPNB type 2 and CC, stratified by T classification. RESULTS: The cohort involved 443 patients with IPNB type 2 (n = 57) and CC (n = 386). In 342 patients with perihilar tumors, 5-year RFS of IPNB type 2 and CC group was 49.8% versus 34.5% (p = .012), respectively. The RFS was 54.6% versus 47.2% (p = .110) for pT1-2 tumors and 28.6% versus 22.7% (p = .436) for pT3-4 tumors, respectively. In 92 patients with distal tumors, 5-year RFS was 47.4% versus 42.1% (p = .678). The RFS was 68.2% versus 49.6% (p = .422) for pT1 tumors and 18.8% versus 38.3% (p = .626) for pT2-3 tumors, respectively. Multivariate analysis identified that poor histologic grade (HR, 2.105; p < .001), microscopic venous invasion (HR, 1.568; p = .002), and nodal metastasis (HR, 1.547; p < .001) were independent prognostic deteriorators, while tumor type (IPNB type 2 vs. CC) was not. CONCLUSIONS: Prognostic impact of IPNB type 2 was limited, suggesting unnecessity of a specific T classification for IPNB type 2 with invasive carcinoma.

Impact of preoperative muscle mass and quality on surgical outcomes in patients undergoing major hepatectomy for perihilar cholangiocarcinoma.

PURPOSES: This study sought to define the impact of skeletal muscle mass and quality on postoperative outcomes in patients with perihilar cholangiocarcinoma. METHODS: Patients who underwent major hepatectomy for perihilar cholangiocarcinoma were included. The normalized total psoas area (TPA) (psoas muscle index [PMI]) and average Hounsfield units of the TPA (psoas muscle density [PMD]) were measured using preoperative computed tomography images. The cohort was dichotomized using the following indices: sex-specific lowest tertile (low PMI and low PMD) and other (normal PMI and normal PMD). Intraoperative and postoperative outcomes were compared, focusing on PMI and PMD. RESULTS: A total of 456 patients were analyzed. The intraoperative blood loss (IBL) was 21.3 ml/kg in the low PMI group and 17.2 ml/kg in the normal PMI group (P = .008). Patients in the low PMI or PMD group experienced postoperative infectious complications more frequently than those in the other groups. The median survival time was 37.8 months in the low PMI group and 54.2 months in the normal PMI group (P = .027). CONCLUSIONS: PMI and PMD were closely associated with IBL and postoperative infectious complications. Additionally, PMI impacted long-term survival. These results suggest an importance of improving muscle mass and quality before surgery.

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.

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.

Comparison of an Inside Stent and a Fully Covered Self-Expandable Metallic Stent as Preoperative Biliary Drainage for Patients with Resectable Perihilar Cholangiocarcinoma.

Background: There is a need for a more tolerable preoperative biliary drainage (PBD) method for perihilar cholangiocarcinoma (PHCC). In recent years, inside stents (ISs) have attracted attention as a less suffering PBD method. Few studies have compared IS with a fully covered self-expandable metallic stent (FCSEMS) as PBD for resectable PHCC. The aim of this study is to compare them. Methods: This study involved 86 consecutive patients (IS: 51; FCSEMS: 35). The recurrent biliary obstruction (RBO) rate until undergoing surgery or being diagnosed as unresectable, time to RBO, factors related to RBO, incidence of adverse events related to endoscopic retrograde cholangiography, and postoperative complications associated with each stent were evaluated retrospectively. Results: There was no significant difference between the two groups in the incidence of adverse events after stent insertion. After propensity score matching, the mean (SD) time to RBO was 37.9 (30.2) days in the IS group and 45.1 (35.1) days in the FCSEMS group, with no significant difference (P=0.912, log-rank test). A total of 7/51 patients in the IS group and 3/35 patients in the FCSEMS group developed RBO. The only risk factor for RBO was bile duct obstruction of the future excisional liver lobe(s) due to stenting (HR 29.8, P=0.008) in the FCSEMS group, but risk factors could not be indicated in the IS group. There was no significant difference in the incidence of bile leakage or liver failure. In contrast, pancreatic fistula was significantly more common in the FCSEMS group (13/23 patients) than in the IS group (3/28 patients) (P < 0.001), especially in patients who did not undergo pancreatectomy (P=0.001). Conclusions: As PBD, both IS and FCSEMS achieved low RBO rates. Compared with FCSEMS, IS shows no difference in RBO rate, is associated with fewer postoperative complications, and is considered an appropriate means of PBD for resectable PHCC. This trail is registered with UMIN000025631.

A proposal of drain removal criteria in hepatobiliary resection.

BACKGROUND: Standardized criteria for drain removal in hepatobiliary resection are lacking. Here, we evaluated the outcomes of delayed removal policy in this extended surgery. METHODS: Patients undergoing hepatectomy with biliary reconstruction between 2012 and 2018 were retrospectively reviewed. The drains were removed on postoperative day (POD) 7 when the drainage fluid was grossly serous, biochemically normal, and negative for bacterial contamination as assessed by Gram staining; additionally, no abnormal fluid collection was confirmed by computed tomography. Clinically relevant abdominal complications (CRACs), including biliary leakage, pancreatic fistula or intra-abdominal abscess, served as the primary outcome measure. RESULTS: Among 374 study patients, surgical drains were removed in 166 (44.3%) patients who met the criteria. Of these patients, 16 (9.6%) patients subsequently required additional drainage due to CRAC. Drains were retained and exchanged in 208 (55.6%) patients who did not meet the criteria. Of these, exchanged drains were soon removed in 34 patients due to no signs of CRAC. The diagnostic ability of the criteria revealed 0.916 sensitivity, 0.815 specificity, and 0.866 accuracy. CONCLUSION: The four findings on POD 7 worked well as criteria for drain removal, and these criteria may be helpful in drain management after hepatobiliary resection.

Early volume loss of skeletal muscle after esophagectomy: a risk for late-onset postoperative pneumonia.

Late-onset postoperative pneumonia (LOPP) after esophagectomy is poorly understood. This study was designed to clarify the features and risk factors for this event. Patients who underwent esophagectomy for esophageal cancer between 2006 and 2016 were included. LOPP was defined as radiologically proven pneumonia that occurred over 3 months after surgery, and clinically relevant late-onset postoperative pneumonia (CR-LOPP) was defined as LOPP that required administration of oxygen and antibiotics in the hospital and/or more intensive treatment. The total psoas muscle area (TPA) was measured using preoperative and postoperative (at 3 months after surgery) computed tomography scan images. Potential risk factors for CR-LOPP were investigated. Among 175 study patients, 46 (26.3%) had LOPP, 29 (16.6%) of whom exhibited CR-LOPP with a cumulative incidence of 15.6% at 3 years and 22.4% at 5 years. Four (13.8%) of these patients died of LOPP. Univariable analysis showed that clinical stage ≥III (P = 0.005), preoperative prognostic nutritional index (PNI) <45 (P = 0.035), arrhythmia (P = 0.014), postoperative hospital stay ≥40 days (P = 0.003), and percent decrease of TPA more than 5% (P < 0.001) were associated with CR-LOPP but not early onset postoperative pneumonia. Multivariable analysis revealed that clinical stage ≥III (hazard ratio [HR] 3.01, P = 0.004), postoperative hospital stay ≥40 days (HR 2.51, P = 0.015), and percent decrease of TPA >5% (HR 9.93, P < 0.001) were independent risk factors for CR-LOPP. CR-LOPP occurred in over 20% of patients at 5 years, and early postoperative loss of TPA was a potential trigger for this delayed complication.