FREE ORALS (FP01-FP31) FP01 e Free papers 1 (mini oral) - Biliary: Introduction: The American Joint Committee on Cancer (AJCC), 8th edition, has revised the T system for distal Cholangiocarcinoma cholangiocarcinoma (DCC) from layer-based to depth- FP01-01 based approach. The aim of this study was to propose an NATIONWIDE TREATMENT, OUTCOME optimal T classification using a measured depth in resect- AND PREDICTORS FOR SURVIVAL IN able DCC. DISTAL CHOLANGIOCARCINOMA Method: Patients who underwent pancreatoduodenectomy for DCC at 32 hospitals between 2001 and 2010 were M. Strijker1, A. Belkouz1, L. G. van der Geest2, included. The distance between the basal lamina and the O. R. Busch1, T. M. van Gulik1, J. Verheij1, advancing cancer cells was measured as depth of invasion J. W. Wilmink1, B. Groot Koerkamp3, H. J. Klümpen1, (DOI). The invasive cancer foci was measured as invasive M. G. Besselink1 and Dutch Pancreatic Cancer Group tumor thickness (ITT). Log-rank c2 was used to determine 1Cancer Center Amsterdam, Academic Medical Center, the cutoff points, and C-index was used to assess the sur- University of Amsterdam, 2Netherlands Comprehensive vival discrimination of each T system. Cancer Organisation (IKNL), and 3Erasmus University Results: Some 404 patients were included. DOI and ITT Medical Center, The Netherlands were measurable in 182 and all patients, and the medians Background: Distal cholangiocarcinoma has a poor were 2.3 and 5.6 mm, respectively. They both showed a prognosis. Published cohorts focusing on distal chol- strong positive correlation (correlation coefficient, 0.854), angiocarcinoma, especially from Western countries, are and the cutoff points of ITT were 1, 5, and 10 mm. The lacking. This study investigated treatment, outcome and median survival time was significantly shortened with in- predictors for survival in a nationwide cohort of patients crease in ITT: 12.4 years for ITT< 1 mm, 5.2 years for with distal cholangiocarcinoma. 1ITT< 5 mm, 3.0 years for 5 ITT< 10 mm, and 1.5 Methods: A population-based cohort derived from the years for ITT10 mm . This 4-tier ITT classification Netherlands Cancer Registry (NCR) was studied. Patients exhibited the most favorable prognostic discrimination, fi with pathologically con rmed distal cholangiocarcinoma, compared to the T systems of AJCC 7th/8th editions (C- resected (2005-2015) and non-resected (2009-2015), were index: 0.6463, 0.6218, and 0.6243). included. Survival was analyzed using Kaplan Meier Conclusions: ITT is a versatile approach for depth methods and multivariable Cox analysis using backward assessment in DCC. The 4-tier ITT classification with selection. cutoff points of 1, 5, and 10 mm can be used as an optimal T fi Results: A total of 794 patients was identi ed; 513 resected system. patients and 321 non-resected patients. Of the resected patients (7.8%) received (neo-)adjuvant treatment. Of 321 non-resected patients, 147 (45.8%) presented with M1 disease and 63 (19.6%) received palliative chemotherapy. FP01-03 Median overall survival for resected, non-resected M0, and EVALUATION OF THE NEW AMERICAN non-resected M1 disease was 23 months (95% CI 21-26), 6 JOINT COMMITTEE ON CANCER months (95% CI 5-8) and 4 months (95% CI 4-5) (p< STAGING MANUAL 8TH EDITION FOR 0.001), respectively. In multivariable analysis, T3/T4 stage PERIHILAR CHOLANGIOCARCINOMA < (p=0.006), higher lymph node ratio (p 0.001), poor dif- 1 1 1 1 ferentiation (p=0.001) and R1 resection (p=0.002) were M. Gaspersz , S. Buettner , J. van Vugt , J. de Jonge , W. Polak1, M. Doukas2, J. Ijzermans1, negative prognostic factors in resected patients. In non- 1 3 resected patients, increasing age (p=0.007), lymph node B. Groot Koerkamp and F. Willemssen 1Surgery, Erasmus MC, University Medical Center metastases (p=0.013), distant metastases (p< 0.001), no Rotterdam, 2Pathology, Erasmus MC, University Medical surgical exploration (p=0.011) and no palliative chemo- Center Rotterdam, and 3Radiology and Nuclear Medicine, therapy (p< 0.001) predicted worse survival. Erasmus MC, University Medical Center Rotterdam, The Discussion: This nationwide, Western study includes the Netherlands largest population with all stages of distal chol- th angiocarcinoma. The study identified predictors for sur- Introduction: To evaluate the 8 edition of the American vival in both the resected and non-resected population Joint Committee on Cancer (AJCC) staging system for which can be useful to stratify future trials with (neo-) perihilar cholangiocarcinoma (PHC), and to compare the th th adjuvant or palliative treatment. prognostic value of the 7 and 8 editions of the AJCC staging system for PHC. Methods: All patients with PHC between 2002-2014 FP01-02 were included. Imaging at the time of presentation was reassessed and AJCC Tumor-Nodal-Metastasis (TNM) PROPOSAL OF AN OPTIMAL DEPTH- stage was determined according to the 7th and 8th edition BASED TUMOR CLASSIFICATION IN of the AJCC staging system. Overall survival (OS) was DISTAL CHOLANGIOCARCINOMA estimated using the Kaplan-Meier method. Comparison H. Aoyama, T. Ebata, Y. Yokoyama, T. Igami, T. Mizuno, of the prognostic accuracy of staging systems was J. Yamaguchi, S. Onoe and M. Nagino performed using the concordance index (c-index) and Nagoya University Graduate School of Medicine, Japan Brier-score. HPB 2018, 20 (S2), S182eS294 Free Orals (FP01-FP31) S183 Results: A total of 248 PHC patients were included. were as good as the prognosis of ICC patients underwent Median OS of the entire cohort was 9.7 months (8.0-11.5). upfront R0 surgery. Prognostic accuracy was comparable between the 7th and Conclusion: If R0 resection is expected, aggressive sur- 8th AJCC staging systems (c-index 0.59 vs 0.58). Prog- gical resection with regional lymph nodes dissection is nostic accuracy of the 8th edition was higher in the sub- recommended in advanced ICC patients with LNM. group of resected patient (0.67), but expanding the staging However, downsizing chemotherapy is useful for patients system with sub-stages lowered the c-index to 0.62. The with initially unresectable locally advanced ICC for prognostic accuracy of the AJCC staging system in unre- improving prognosis. sectable patients was poor with a c-index of 0.57 in both the normal and expanded staging system. th th Conclusions: The 7 and 8 editions of the AJCC staging FP01-05 system for PHC have comparable prognostic accuracy. A COMPARISON OF TREATMENT AND Although developed to be used for resectable and unre- sectable patients, the discriminative performance in unre- OUTCOMES OF PERIHILAR sectable patients was poor. Therefore, the AJCC staging CHOLANGIOCARCINOMA IN AN system may need modifications to improve its prognostic EASTERN AND WESTERN CENTER accuracy in patients with unresectable PHC, compromising P. Olthof1,2, M. Miyasaka3, W. Jarnagin4, the majority of patients. T. van Gulik1 and T. Noij3 1Academic Medical Center Amsterdam, 2Syrgeru, Reinier de Graaf Gasthuis, The Netherlands, 3Hokkaido Univer- FP01-04 sity Graduate School of Medicine, Japan, and 4Memorial MULTIDISCIPLINARY TREATMENT Sloan Kettering Cancer Center, United States COMBINED WITH NEOADJUVANT Background: Perihilar cholangiocarcinoma (PHC) is a rare DOWNSIZING CHEMOTHERAPY AND tumor that requires multimodal multidisciplinary treatment AGGRESSIVE REGIONAL LYMPH and is associated with substantial morbidity and mortality. Treatment strategies and outcomes vary greatly between NODE DISSECTION TO ACHIEVE R0 the eastern and western parts of the world. This study aimed RESECTION IMPROVES PROGNOSIS IN to compare a major eastern and western PHC cohort in PATIENTS WITH ADVANCED terms of patient characteristics, treatment strategies and INTRAHEPATIC outcomes including a propensity score matched analysis. CHOLANGIOCARCINOMA Methods: All consecutive patients who underwent com- bined biliary and liver resection for PHC between 2005 and S. Kuboki, H. Yoshitomi, K. Furukawa, T. Takayashiki, 2016 at two western and one eastern center were included. S. Takano, M. Miyazaki and M. Ohtsuka A propensity score matched analysis based on baseline Department of General Surgery, Graduate School of characteristics to compare perioperative outcomes and a Medicine, Chiba University, Japan multivariable analysis for survival were performed. Background: R0 resection is the only chance for long-term Results: A total of 210 western patients were compared to survival in patients with intrahepatic cholangiocarcinoma 164 eastern patients. After propensity score matching (1:1), (ICC); however, the prognosis of ICC with lymph node the two cohorts both including 79 patients had similar rates metastasis (LNM) is poor and sometimes difficult to of liver failure and morbidity, however biliary leakage achieve R0 resection. (33% versus 17%, p=0.03) and morality rates (18% versus Aim: To evaluate the usefulness of neoadjuvant downsiz- 5%) were higher in the west. Despite matching based on ing chemotherapy and aggressive regional lymph node liver volume, portal vein embolization was more frequent dissection to achieve R0 resection for improving prognosis. in the east (58% versus 11%, p< 0.01). At multivariable Methods: 135 ICC patients underwent R0/R1 resection analysis, western patients had inferior survival compared to were enrolled. For control, 28 locally advanced ICC pa- the east (hazard-ratio 1.72 (1-23-2.40) P < 0.01) corrected tients receiving chemotherapy only (gemcitabine, cispla- for age, ASA score, tumor stage and margin. tine, or S-1) were selected. Discussion: There are major differences in patient charac- Results: Larger tumor size, positive vascular/lymphatic teristics, treatment strategies, perioperative outcomes and invasion, positive intrahepatic metastasis, positive LNM, survival between eastern and western PHC cohorts. These and R1 resection were significant risk factors for poorer results indicate that PHC research should not be translated prognosis. R1 resection was the strongest prognostic across the world before cross-cardinal external validation factor. When prognostic factors in R0 cases were further evaluated, positive LNM was an independent risk factor for poorer prognosis. However, even though LNM FP01-06 existed, aggressive R0 resection improved prognosis.