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Purpose: Intrahepatic cholangiocarcinoma (IHC) is a heterogeneous tumor. The hidden-genome classifier, a supervised machine learning-based algorithm, was used to quantify tumor heterogeneity and improve classification., Experimental Design: A retrospective review of 1,370 patients with IHC, extrahepatic cholangiocarcinoma (EHC), gallbladder cancer (GBC), hepatocellular carcinoma (HCC), or biphenotypic tumors was conducted. A hidden-genome model classified 527 IHC based on genetic similarity to EHC/GBC or HCC. Genetic, histologic, and clinical data were correlated., Results: In this study, 410 IHC (78%) had >50% genetic homology with EHC/GBC; 122 (23%) had >90% homology ("biliary class"), characterized by alterations of KRAS, SMAD4, and CDKN2A loss; 117 IHC (22%) had >50% genetic homology with HCC; and 30 (5.7%) had >90% homology ("HCC class"), characterized by TERT alterations. Patients with biliary- versus non-biliary-class IHC had median overall survival (OS) of 1 year (95% CI, 0.77, 1.5) versus 1.8 years (95% CI, 1.6, 2.0) for unresectable disease and 2.4 years (95% CI, 2.1, NR) versus 5.1 years (95% CI, 4.8, 6.9) for resectable disease. Large-duct IHC (n = 28) was more common in the biliary class (n = 27); the HCC class was composed mostly of small-duct IHC (64%, P = 0.02). The hidden genomic classifier predicted OS independent of FGFR2 and IDH1 alterations. By contrast, the histology subtype did not predict OS., Conclusions: IHC genetics form a spectrum with worse OS for tumors genetically aligned with EHC/GBC. The classifier proved superior to histologic subtypes for predicting OS independent of FGFR2 and IDH1 alterations. These results may explain the differential treatment responses seen in IHC and may direct therapy by helping stratify patients in future clinical trials., (©2024 American Association for Cancer Research.)

Background: Combined hepatocellular-cholangiocarcinoma liver tumors (cHCC-CCA) with pathologic differentiation of both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma within the same tumor are not traditionally considered for liver transplantation due to perceived poor outcomes. Published results are from small cohorts and single centers. Through a multicenter collaboration, we performed the largest analysis to date of the utility of liver transplantation for cHCC-CCA., Study Design: Liver transplant and resection outcomes for HCC (n = 2,998) and cHCC-CCA (n = 208) were compared in a 12-center retrospective review (2009 to 2017). Pathology defined tumor type. Tumor burden was based on radiologic Milan criteria at time of diagnosis and applied to cHCC-CCA for uniform analysis. Kaplan-Meier survival curves and log-rank test were used to determine overall survival and disease-free survival. Cox regression was used for multivariate survival analysis., Results: Liver transplantation for cHCC-CCA (n = 67) and HCC (n = 1,814) within Milan had no significant difference in overall survival (5-year cHCC-CCA 70.1%, HCC 73.4%, p = 0.806), despite higher cHCC-CCA recurrence rates (23.1% vs 11.5% 5 years, p < 0.001). Irrespective of tumor burden, cHCC-CCA tumor patient undergoing liver transplant had significantly superior overall survival (p = 0.047) and disease-free survival (p < 0.001) than those having resection. For cHCC-CCA within Milan, liver transplant was associated with improved disease-free survival over resection (70.3% vs 33.6% 5 years, p < 0.001)., Conclusions: Regardless of tumor burden, outcomes after liver transplantation are superior to resection for patients with cHCC-CCA. Within Milan criteria, liver transplant for cHCC-CCA and HCC result in similar overall survival, justifying consideration of transplantation due to the higher chance of cure with liver transplantation in this traditionally excluded population., (Copyright © 2020 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)

Intrahepatic cholangiocarcinomas are histologically heterogenous. Using a cohort of 184 clinically defined, resected intrahepatic cholangiocarcinomas, we retrospectively classified the histology into 4 subtypes: large duct (LD), small duct (SD) (predominantly tubular [SD1] or predominantly anastomosing/cholangiolar, [SD2]), or indeterminate. Then, we tested the 4 subtypes for associations with risk factors, patient outcomes, histology, and immunophenotypic characteristics. SD was the most common (84%; 24% SD1 and 60% SD2) with lower proportions of LD (8%), and indeterminate (8%). Primary sclerosing cholangitis was rare (2%), but correlated with LD (P=0.005). Chronic hepatitis, frequent alcohol use, smoking, and steatosis had no histologic association. LD was associated with mucin production (P<0.001), perineural invasion (P=0.002), CA19-9 staining (P<0.001), CK7, CK19, CD56 immunophenotype (P=0.005), and negative albumin RNA in situ hybridization (P<0.001). SD was histologically nodular (P=0.019), sclerotic (P<0.001), hepatoid (P=0.042), and infiltrative at the interface with hepatocytes (P<0.001). Albumin was positive in 71% of SD and 18% of LD (P=0.0021). Most albumin positive tumors (85%) lacked extracellular mucin (P<0.001). S100P expression did not associate with subtype (P>0.05). There was no difference in disease-specific or recurrence-free survival among the subtypes. Periductal infiltration and American Joint Committee on Cancer eighth edition pT stage predicted survival by multivariable analysis accounting for gross configuration, pT stage, and histologic type. pT2 had worse outcome relative to other pT stages. Significant differences in histology and albumin expression distinguish LD from SD, but there is insufficient evidence to support further subclassification of SD.

Through exomic sequencing of 32 intrahepatic cholangiocarcinomas, we discovered frequent inactivating mutations in multiple chromatin-remodeling genes (including BAP1, ARID1A and PBRM1), and mutation in one of these genes occurred in almost half of the carcinomas sequenced. We also identified frequent mutations at previously reported hotspots in the IDH1 and IDH2 genes encoding metabolic enzymes in intrahepatic cholangiocarcinomas. In contrast, TP53 was the most frequently altered gene in a series of nine gallbladder carcinomas. These discoveries highlight the key role of dysregulated chromatin remodeling in intrahepatic cholangiocarcinomas.

Replication-competent oncolytic herpes simplex viruses (HSV), modified by deletion of certain viral growth genes, can selectively target malignant cells. The viral growth gene gamma(1)34.5 has significant homology to GADD34 (growth arrest and DNA damage protein 34), which promotes cell cycle arrest and DNA repair in response to stressors such as radiation (XRT). By upregulating GADD34, XRT may result in greater oncolytic activity of HSV strains deficient in the gamma(1)34.5 gene. The human cholangiocarcinoma cell lines KMBC, SK-ChA-1 and YoMi were treated with NV1023, an oncolytic HSV lacking one copy of gamma(1)34.5. Viral proliferation assays were performed at a multiplicity of infection (MOI, number of viral particles per tumor cell) equal to 1, either alone or after XRT at 250 or 500 cGy. Viral replication was assessed by plaque assay. In vitro cytotoxicity assays were performed using virus at MOIs of 0.01 and 0.1, with or without XRT at 250 cGy and cell survival determined with lactate dehydrogenase assay. Established flank tumors in athymic mice were treated with a single intratumoral injection of virus (10(3) or 10(4) plaque forming units), either alone or after a single dose of XRT at 500 cGy, and tumor volumes measured. RT-PCR was used to measure GADD34 mRNA levels in all cell lines after a single dose of XRT at 250 or 500 cGy. NV1023 was tumoricidal in all three cell lines, but sensitivity to the virus varied. XRT enhanced viral replication in vitro in all cell lines. Combination treatment with low-dose XRT and virus was highly tumoricidal, both in vitro and in vivo. The greatest tumor volume reduction with combination therapy was seen with YoMi cells, the only cell line with increased GADD34 expression after XRT and the only cell line in which a synergistic treatment effect was suggested. In KMBC and SK-ChA-1 cells, neither of which showed increased GADD34 expression after XRT, tumor volume reduction was less pronounced and there was no suggestion of a synergistic effect in either case. Oncolytic HSV are effective in treating human cholangiocarcinoma cell lines, although sensitivity to virus varies. XRT-enhanced viral replication occurs through a mechanism that is not necessarily dependent on GADD34 upregulation. However, XRT-induced upregulation of GADD34 further promotes tumoricidal activity in viral strains deficient in the gamma(1)34.5 gene, resulting in treatment synergy; this effect is cell type dependent. Combined XRT and oncolytic viral therapy is a potentially important treatment strategy that may enhance the therapeutic ratios of both individual therapies.

Peripheral/Intrahepatic Cholangiocarcinoma (IHC), a malignant epithelial tumor originating from the intrahepatic bile ducts, is the second most common primary liver cancer after hepatocellular carcinoma. Unlike hepatocellular carcinoma, however, IHC is infrequently associated with chronic underlying liver disease. A recent study from the United States has demonstrated a 9% annual percentage increase and an overall 10-fold increase in mortality related to IHC since 1973. Despite this observation, however, IHC remains a rare disease in Western countries. Of the approximately 4000 patients seen at Memorial Sloan-Kettering Cancer Center with hepatic lesions since from 1995-2001, 7% had a diagnosis of cholangiocarcinoma and only 1% had IHC. As a result, progress in elucidating the pathogenesis and clinical behavior of these tumors has been slow. However, the increasing number of reports in recent years has increased awareness of IHC and provided some insight into its biology. At present, complete resection is the only therapy that offers the possibility of long-term survival. Single agent or combination chemotherapy and radiation therapy have not been shown to have a significant impact, either as primary treatment or as an adjuvant to resection. This report reviews the relevant literature pertaining to IHC with emphasis on clinical presentation, radiologic evaluation, treatment and outcome.

Background: There has been an increasing incidence and mortality from peripheral cholangiocarcinoma (PC) in the United States over the past 24 years. PC has been classified into two principal types, a mass-forming type and a periductal-infiltrating type, with a significant difference in the clinical behavior between the two. A third type, demonstrating a noninvasive intraductal growth of PC, was described as papillary PC. Rarely, papillary hepatic tumors composed of oncocytic cells have been described. Intraductal oncocytic papillary carcinomas (IOPCs) of the liver present as large, mucin-filled, cystic lesions lined by noninvasive or focally microinvasive oncocytic tumors., Methods: From June 1999 to August 2001, three patients with hepatic IOPCs were identified in the files of the Hepatobiliary Service, Department of Surgery, and the Department of Pathology at Memorial Sloan-Kettering Cancer Center. They form the basis of this study. We report the clinicopathologic presentation, as well as the outcome, with a review of the literature., Results: All three cases presented with well defined intrahepatic cystic masses ranging in size from 7.2 to 21.1 cm. The most prominent cells of the lining epithelium were columnar with oncocytic features showing abundant eosinophilic granular cytoplasm and centrally located nucleoli. All three patients underwent resection with one demonstrating local bile duct recurrence that was managed with stenting. Review of the literature has identified 39 patients with papillary PC and 2 patients with IOPC. The biology of these reported cases has been variable with overall survival better than that of nonpapillary PC patients, with recurrence in 15% of the reported cases., Conclusion: Papillary PC is a rare type of cholangiocarcinoma that includes an interesting variant: IOPC. These tumors are predominantly found in men, who present with large (> 5 cm) mucinous cystic lesions of the bile duct. A noninvasive histology is seen, and long-term survival may be achieved with complete resection. Invasive variants of IOPC have been reported in the literature and have a worse overall prognosis., (Copyright 2002 American Cancer Society.)

Combined hepatocellular-cholangiocarcinoma (CHC) forms a small but significant proportion of primary liver carcinomas. However, its diagnostic features are not well established, and this has possibly contributed to the variability in its reported clinical outcome in the literature. Many such tumors with features intermediate between hepatocellular carcinoma and cholangiocarcinoma (CC) may have been considered CC in the past based on positivity for "biliary differentiation" cytokeratins and the lack of availability of highly sensitive and specific hepatocellular markers. The utility of in situ hybridization for albumin mRNA, a recently available sensitive and specific hepatocellular marker, has not been reported in CHC. We investigated 27 CHCs with regard to their histomorphologic spectrum and association of these morphologies with immunohistochemical staining for different cytokeratins (CK7, CK19, and CK20; AE1; Cam 5.2), epithelial membrane antigen, polyclonal carcinoembryonic antigen and alpha-fetoprotein, and in situ hybridization for albumin mRNA. All 27 tumors contained areas morphologically intermediate between hepatocellular carcinoma and CC (transitional-type tumors), and in each case such areas formed at least 25% of the tumor. Nine (33%) tumors showed areas with "antler-like" morphology, a feature not previously described in CHC. Twenty-two of 23 tumors (96%) showed positive signals on in situ hybridization for albumin mRNA. Positivity for both hepatocellular (albumin mRNA) and biliary (keratin immunohistochemical profile) markers confirmed the light microscopic impression of biphenotypic differentiation in these tumors. Immunohistochemical positivity for all cytokeratins (except CK7) and epithelial membrane antigen, as well as the expression of albumin mRNA by in situ hybridization, did not show significant differences between hepatocellular carcinoma and CC-like areas. Based on the cytokeratin profile and results on polyclonal carcinoembryonic antigen/alpha-fetoprotein alone, many such tumors would be classified as CC. However, the positivity for albumin mRNA by in situ hybridization proves that such an interpretation would not have been accurate. Clinically, CHCs showed many differences from pure hepatocellular carcinoma, including the absence of cirrhosis (0 of 27), rarity of serum hepatitis B or C marker positivity (4 of 27), and normal to only mildly elevated serum alpha-fetoprotein levels (median 187 ng/mL). The tumor followed an aggressive clinical course, with overall 3-and 5-year survival rates of 30% and 18%, and in the resected cases of 38% and 24%, respectively.

Background: Evaluation of peritoneal cytology provides valuable staging information in patients with gastric and pancreatic adenocarcinoma, but its usefulness in patients with extrahepatic cholangiocarcinoma is unclear. The aim of this study was to evaluate the predictive value of peritoneal cytology in patients with potentially resectable hilar cholangiocarcinoma. This study evaluated a possible association between positive peritoneal cytology and percutaneous transhepatic biliary drainage, which is commonly used in these patients and may result in peritoneal biliary leakage and peritoneal seeding., Study Design: From October 1997 through June 2000 26 patients with hilar cholangiocarcinoma underwent staging laparoscopy immediately before planned open exploration and resection. Peritoneal washings were obtained during laparoscopic examination before any biopsies were taken. Cytologic analysis was performed using the Papanicolau technique., Results: There were 18 men and 8 women, with a median age of 69 years (range 42 to 81 years). The most common presenting symptom was jaundice (n = 19). Previous biliary drainage was performed in 23 patients: 9 percutaneous and 14 endoscopic. Metastatic disease was suspected preoperatively in six patients, three to the liver, two to the peritoneum, and one to regional lymph nodes, all of which were confirmed at laparoscopy. Laparoscopy identified five additional patients with metastatic disease. Peritoneal cytology was positive for malignant cells in two patients, both of whom had gross peritoneal metastases. Nine other patients had metastatic disease to distant sites within the abdomen, but none had positive cytology. Overall, six patients had metastatic disease to the peritoneal cavity, only one of whom had undergone earlier percutaneous biliary drainage., Conclusions: Peritoneal cytology was not predictive of occult metastatic disease. Laparoscopic staging identified some patients with unresectable hilar cholangiocarcinoma, but analysis of peritoneal cytology provided no additional information. There was no association between percutaneous transhepatic biliary drainage and peritoneal tumor seeding.

Objective: To analyze resectability and survival in patients with hilar cholangiocarcinoma according to a proposed preoperative staging scheme that fully integrates local, tumor-related factors., Summary Background Data: In patients with hilar cholangiocarcinoma, long-term survival depends critically on complete tumor resection. The current staging systems ignore factors related to local tumor extent, preclude accurate preoperative disease assessment, and correlate poorly with resectability and survival., Methods: Demographics, results of imaging studies, surgical findings, pathology, and survival were analyzed prospectively in consecutive patients. Using data from imaging studies, all patients were placed into one of three stages based on the extent of ductal involvement by tumor, the presence or absence of portal vein compromise, and the presence or absence of hepatic lobar atrophy., Results: From March 1991 through December 2000, 225 patients were evaluated, 77% of whom were seen and treated within the last 6 years. Sixty-five patients had unresectable disease; 160 patients underwent exploration with curative intent. Eighty patients underwent resection: 62 (78%) had a concomitant hepatic resection and 62 (78%) had an R0 resection (negative histologic margins). Negative histologic margins, concomitant partial hepatectomy, and well-differentiated tumor histology were associated with improved outcome after all resections. However, in patients who underwent an R0 resection, concomitant partial hepatectomy was the only independent predictor of long-term survival. Of the 9 actual 5-year survivors (of 30 at risk), all had a concomitant hepatic resection and none had tumor-involved margins; 3 of these 9 patients remained free of disease at a median follow-up of 88 months. The rates of complications and death after resection were 64% and 10%, respectively. In the 219 patients whose disease could be staged, the proposed system predicted resectability and the likelihood of an R0 resection and correlated with metastatic disease and survival., Conclusion: By taking full account of local tumor extent, the proposed staging system for hilar cholangiocarcinoma accurately predicts resectability, the likelihood of metastatic disease, and survival. Complete resection remains the only therapy that offers the possibility of long-term survival, and hepatic resection is a critical component of the surgical approach.

Intrahepatic cholangiocarcinoma (IHC) is a rare primary hepatic tumor of bile duct origin for which resection is the most effective treatment. But resectability, outcomes after resection, and recurrence patterns have not been well described. Patients with IHC were identified from a prospective database. Demographic data, tumor characteristics, and outcomes were analyzed. From March 1992 to September 2000, 53 patients with hepatic tumors underwent exploration and were found to have pure IHC on pathologic analysis. Patients with mixed hepatocellular and cholangiocarcinoma tumors were excluded. At exploration, 20 patients were unresectable for an overall resectability rate of 62% (33 of 53). Median survival for patients submitted to resection was 37.4 months versus 11.6 months for patients undergoing biopsy only (p = 0.006; median followup for surviving patients, 15.6 months). Actuarial 3-year survival was 55% versus 21%, respectively. Factors predictive of poor survival after resection included vascular invasion (p = 0.0007), histologically positive margin (p = 0.009), or multiple tumors (p = 0.003). After resection, 20 of 33 patients (61%) recurred at a median of 12.4 months. Sites of recurrence included the liver (14), retroperitoneal or hilar nodes (4), lung (4), and bone (2). The median disease-free survival was 19.4 months, with a 3-year disease-free survival rate of 22%. Factors predictive of recurrence were multiple tumors (p = 0.0002), tumor size (p = 0.001), and vascular invasion (p = 0.01). About two-thirds of patients who appeared resectable on preoperative imaging were amenable to curative resection at the time of operation. Although complete resection improved survival, recurrence was common. The majority of recurrences were local or regional, which may help guide future adjuvant therapy strategies.

Malignancies of the biliary tree, particularly the extrahepatic bile ducts, remain difficult clinical problems. Because experience with these uncommon tumors has been limited to a small number of centers, meaningful clinical trials have been difficult to perform. Complete resection remains the most effective therapy, but is usually possible in the minority of patients. Palliating the effects of biliary obstruction is thus often the primary therapeutic goal. Chemotherapy and radiation therapy have not been proven to reduce the incidence of recurrence after resection nor to improve survival in patients with unresectable disease. This review focuses on cholangiocarcinoma of the extrahepatic bile ducts.

Background: The indications for preoperative biliary stenting in patients with obstructive jaundice are controversial. We evaluated the effect of preoperative biliary stenting on bacterobilia and infectious complications following surgical treatment of proximal cholangiocarcinoma., Design: A retrospective review was performed of all patients undergoing surgical treatment of proximal cholangiocarcinoma., Setting: A metropolitan cancer surgery service., Patients and Methods: Seventy-one patients underwent palliative biliary bypass or curative resection of proximal cholangiocarcinoma from March 1, 1991, to April 1, 1997, and were entered into a prospective database. Forty-one patients underwent preoperative biliary intubation and stent placement. We analyzed patient, nutritional, laboratory, and operating room factors. Statistical evaluation was performed using Student t test and chi2 analysis., Main Outcome Measure: Data were recorded for a history of cholangitis, operative time, amount of blood loss, incidence of intraoperative bacterobilia, proportion of patients with postoperative infectious and noninfectious complications, and length of hospital stay., Results: All patients (n = 14) with a history of preoperative cholangitis had been subjected to previous endoscopic retrograde cholangiopancreatography and/or percutaneous transhepatic biliary drainage. Groups were equivalent for risk for comorbidity, proportion undergoing curative vs palliative procedures, time spent in the operating room, and amount of blood loss. Patients with stents had a significantly lower bilirubin level (P = .005). Patients with stents had a significantly increased risk for bacterobilia (P = .001) and infectious complications (P = .03). Bacterobilia was present in 11 (100%) of 11 patients undergoing endoscopic stenting and in 15 (65%) of 23 patients undergoing percutaneous stenting. There was no increased risk for noninfectious complications, length of hospital stay, or mortality in patients with stents. In 10 (59%) of 17 patients with postoperative infectious complications and positive findings of intraoperative bile culture, the organism was synonymous., Conclusions: Preoperative biliary stenting in proximal cholangiocarcinoma increases the incidence of contaminated bile and postoperative infectious complications. Endoscopic stents frequently do not relieve jaundice in high biliary obstruction and are rarely indicated, especially in light of their high contamination rate.

Objectives: To determine the resectability rate for hilar cholangiocarcinoma, to analyze reasons for unresectability, and to devise a presurgical clinical T-staging system., Methods: Ninety patients with hilar cholangiocarcinomas seen between March 1, 1991, and April 1, 1997, were evaluated. Accurate patterns of disease progression and therapy were evaluable. Disease was staged in 87 patients using extent of ductal tumor involvement, portal vein compromise, and liver atrophy., Results: In 21 patients, disease was deemed unresectable for cure at presentation. In 39 patients, disease was found to be unresectable at laparotomy, 23 secondary to nodal (N2) or distant metastases. Unresectability was the result of metastases in 52% and of locally advanced disease in 28%. Thirty patients (33%) had resection of all gross disease, and 25 of these (83%) had negative histologic margins. Twenty-two patients underwent partial hepatectomy. The 30-day mortality rate was 7%. Projected survival is greater than 60 months in those with a negative histologic margin, with a median follow-up of 26 months. A presurgical T-staging system allows presurgical selection for therapy, predicts partial hepatectomy, and offers an index of prognosis., Conclusions: In half the patients, unresectability is mainly the result of intraabdominal metastases. Presurgical imaging predicts unresectability based on local extension but is poor for assessing nodal metastases. In one third of patients, disease can be resected for cure with a long median survival. Curative resection depends on negative margins, and hepatic resection is necessary to achieve this. The T-staging system correlates with resectability, the need for hepatectomy, and overall survival.

Background: This study reports the results of hepatic arterial infusion (HAI) with floxuridine (FUDR) and dexamethasone (dex) in patients with unresectable intrahepatic cholangiocarcinoma (ICC) or hepatocellular carcinoma (HCC) and investigates dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) assessment of tumor vascularity as a biomarker of outcome. Patients and methods: Thirty-four unresectable patients (26 ICC and eight HCC) were treated with HAI FUDR/dex.Radiologic dynamic and pharmacokinetic parameters related to tumor perfusion were analyzed and correlated with response and survival. Results: Partial responses were seen in 16 patients (47.1%); time to progression and response duration were 7.4 and 11.9 months, respectively. Median follow-up and median survival were 35 and 29.5 months, respectively; 2-year survival was 67%. DCE-MRI data showed that patients with pretreatment integrated area under the concentration curve of gadolinium contrast over 180 s (AUC 180) >34.2 mM⋅s had a longer median survival than those with AUC 180<34 mM⋅s (35.1 versus 19.1 months, P = 0.002). Decreased volume transfer exchange between the vascular space and extracellular extravascular space (-ΔKtrans) and the corresponding rate constant (-Δkep) on the first posttreatment scan both predicted survival. Conclusions: In patients with unresectable primary liver cancer, HAI therapy can be effective and safe. Pretreatment and early post-treatment changes in tumor perfusion characteristics may predict treatment outcome. [ABSTRACT FROM PUBLISHER]

The article offers information on the surgery for perihilar cholangiocarcinoma. Topics discussed include its risk factors such as sclerosing cholangitis and lifetime cancer; usage of abdominal Computed tomography (CT) and magnetic resonance cholangiopancreatography (MRCP) in the diagnosis; and the issues relating to the increased carbohydrate antigen in patients.

Background: The objective of this study was to derive and validate a prognostic nomogram to predict disease-specific survival (DSS) after a curative intent resection of perihilar cholangiocarcinoma (PHC). Patients and methods: A nomogram was developed from 173 patients treated at Memorial Sloan Kettering Cancer Center (MSKCC), New York, USA. The nomogram was externally validated in 133 patients treated at the Academic Medical Center (AMC), Amsterdam, The Netherlands. Prognostic accuracy was assessed with concordance estimates and calibration, and compared with the American Joint Committee on Cancer (AJCC) staging system. The nomogram will be available as web-based calculator at mskcc.org/nomograms. Results: For all 306 patients, the median overall survival (OS) was 40 months and the median DSS 41 months. Median follow-up for patients alive at last follow-up was 48 months. Lymph node involvement, resection margin status, and tumor differentiation were independent prognostic factors in the derivation cohort (MSKCC). A nomogram with these prognostic factors had a concordance index of 0.73 compared with 0.66 for the AJCC staging system. In the validation cohort (AMC), the concordance index was 0.72, compared with 0.60 for the AJCC staging system. Calibration was good in the derivation cohort; in the validation cohort patients had a better median DSS than predicted by the model. Conclusions: The proposed nomogram to predict DSS after curative intent resection of PHC had a better prognostic accuracy than the AJCC staging system. Calibration was suboptimal because DSS differed between the two institutions. The nomogram can inform patients and physicians, guide shared decision making for adjuvant therapy, and stratify patients in future randomized, controlled trials. [ABSTRACT FROM AUTHOR]