Analysis of Plasma Circulating Tumor DNA in Borderline Resectable Pancreatic Cancer Treated with Neoadjuvant Modified FOLFIRINOX: Clinical Relevance of DNA Damage Repair Gene Alteration Detection / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#There are no reliable biomarkers to guide treatment for patients with borderline resectable pancreatic cancer (BRPC) in the neoadjuvant setting. We used plasma circulating tumor DNA (ctDNA) sequencing to search biomarkers for patients with BRPC receiving neoadjuvant mFOLFIRINOX in our phase 2 clinical trial (NCT02749136). @*Materials and Methods@#Among the 44 patients enrolled in the trial, patients with plasma ctDNA sequencing at baseline or post-operation were included in this analysis. Plasma cell-free DNA isolation and sequencing were performed using the Guardant 360 assay. Detection of genomic alterations, including DNA damage repair (DDR) genes, were examined for correlations with survival. @*Results@#Among the 44 patients, 28 patients had ctDNA sequencing data qualified for the analysis and were included in this study. Among the 25 patients with baseline plasma ctDNA data, 10 patients (40%) had alterations of DDR genes detected at baseline, inclu-ding ATM, BRCA1, BRCA2 and MLH1, and showed significantly better progression-free survival than those without such DDR gene alterations detected (median, 26.6 vs. 13.5 months; log-rank p=0.004). Patients with somatic KRAS mutations detected at baseline (n=6) had significantly worse overall survival (median, 8.5 months vs. not applicable; log-rank p=0.003) than those without. Among 13 patients with post-operative plasma ctDNA data, eight patients (61.5%) had detectable somatic alterations. @*Conclusion@#Detection of DDR gene mutations from plasma ctDNA at baseline was associated with better survival outcomes of pati-ents with borderline resectable pancreatic ductal adenocarcinoma treated with neoadjuvant mFOLFIRINOX and may be a prognostic biomarker.

Survival Benefit of Adjuvant Chemotherapy in Patients with Pancreatic Ductal Adenocarcinoma Who Underwent Surgery Following Neoadjuvant FOLFIRINOX / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The benefit of adjuvant chemotherapy following curative-intent surgery in pancreatic ductal adenocarcinoma (PDAC) patients who had received neoadjuvant FOLFIRINOX is unclear. This study aimed to assess the survival benefit of adjuvant chemotherapy in this patient population. @*Materials and Methods@#This retrospective study included 218 patients with localized non-metastatic PDAC who received neoadjuvant FOLFIRINOX and underwent curative-intent surgery (R0 or R1) between January 2017 and December 2020. The association of adjuvant chemotherapy with disease-free survival (DFS) and overall survival (OS) was evaluated in overall patients and in the propensity score matched (PSM) cohort. Subgroup analysis was conducted according to the pathology-proven lymph node status. @*Results@#Adjuvant chemotherapy was administered to 149 patients (68.3%). In the overall cohort, the adjuvant chemotherapy group had significantly improved DFS and OS compared to the observation group (DFS: median, 13.8 months [95% confidence interval (CI), 11.0 to 19.1] vs. 8.2 months [95% CI, 6.5 to 12.0]; p < 0.001; and OS: median, 38.0 months [95% CI, 32.2 to not assessable] vs. 25.7 months [95% CI, 18.3 to not assessable]; p=0.005). In the PSM cohort of 57 matched pairs of patients, DFS and OS were better in the adjuvant chemotherapy group than in the observation group (p < 0.001 and p=0.038, respectively). In the multivariate analysis, adjuvant chemotherapy was a significant favorable prognostic factor (vs. observation; DFS: hazard ratio [HR], 0.51 [95% CI, 0.36 to 0.71; p < 0.001]; OS: HR, 0.45 [95% CI, 0.29 to 0.71; p < 0.001]). @*Conclusion@#Among PDAC patients who underwent surgery following neoadjuvant FOLFIRINOX, adjuvant chemotherapy may be associated with improved survival. Randomized studies should be conducted to validate this finding.

Diagnostic model for pancreatic cancer using a multi-biomarker panel

Purpose@#Diagnostic biomarkers of pancreatic ductal adenocarcinoma (PDAC) have been used for early detection to reduce its dismal survival rate. However, clinically feasible biomarkers are still rare. Therefore, in this study, we developed an automated multi-marker enzyme-linked immunosorbent assay (ELISA) kit using 3 biomarkers (leucine-rich alpha-2-glycoprotein [LRG1], transthyretin [TTR], and CA 19-9) that were previously discovered and proposed a diagnostic model for PDAC based on this kit for clinical usage. @*Methods@#Individual LRG1, TTR, and CA 19-9 panels were combined into a single automated ELISA panel and tested on 728 plasma samples, including PDAC (n = 381) and normal samples (n = 347). The consistency between individual panels of 3 biomarkers and the automated multi-panel ELISA kit were accessed by correlation. The diagnostic model was developed using logistic regression according to the automated ELISA kit to predict the risk of pancreatic cancer (high-, intermediate-, and low-risk groups). @*Results@#The Pearson correlation coefficient of predicted values between the triple-marker automated ELISA panel and the former individual ELISA was 0.865. The proposed model provided reliable prediction results with a positive predictive value of 92.05%, negative predictive value of 90.69%, specificity of 90.69%, and sensitivity of 92.05%, which all simultaneously exceed 90% cutoff value. @*Conclusion@#This diagnostic model based on the triple ELISA kit showed better diagnostic performance than previous markers for PDAC. In the future, it needs external validation to be used in the clinic.

Adjuvant Chemotherapy for Resected Ampulla of Vater Carcinoma: Retrospective Analysis of 646 Patients / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. @*Materials and Methods@#Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. @*Results@#The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). @*Conclusion@#AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Adjuvant Chemotherapy for Resected Ampulla of Vater Carcinoma: Retrospective Analysis of 646 Patients / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. @*Materials and Methods@#Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. @*Results@#The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). @*Conclusion@#AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Prognostic factors predicting survival rate over 10 years of patients with intrahepatic cholangiocarcinoma after hepatic resection

PURPOSE: Hepatic resection is considered as the optimal treatment for intrahepatic cholangiocarcinoma (IHCC); however, the survival rate after resection is low and the analysis of long-term (≥10 years) survivors is rare. This study aims to analyze the clinicopathological factors affecting the long-term survival of patients with IHCC.METHODS: Between January 2003 and December 2012, a single-institution cohort of 429 patients who underwent hepatic resection for IHCC were reviewed retrospectively. Surgical results, recurrence, and survival rates were investigated, and multivariate analyses were performed to identify prognostic factors.RESULTS: The overall 1- , 3- , 5- and 10-year survival rates of patients were 76.5%, 44.1%, 33.3%, and 25.1%, respectively. Multivariate analysis showed that the serum CA 19-9 level (≥38 U/mL) (P < 0.001), lymph node (LN) metastasis (P = 0.001), and lymphovascular invasion (LVI) (P = 0.012) were independent factors associated with overall survival. In particular, CA 19-9 level and histologic type were determined to be independent factors affecting survival for more than 10 years.CONCLUSION: CA 19-9 (≥38 U/mL), LN metastasis, and LVI were identified as independent risk factors for survival after resection of IHCC. CA 19-9 (<38 U/mL) and histologic type were independent factors predicting survival for more than 10 years.

Lymph node size and its association with nodal metastasis in ductal adenocarcinoma of the pancreas

Background@#Although lymph node metastasis is a poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC), our understanding of lymph node size in association with PDAC is limited. Increased nodal size in preoperative imaging has been used to detect node metastasis. We evaluated whether lymph node size can be used as a surrogate preoperative marker of lymph node metastasis. @*Methods@#We assessed nodal size and compared it to the nodal metastatic status of 200 patients with surgically resected PDAC. The size of all lymph nodes and metastatic nodal foci were measured along the long and short axis, and the relationships between nodal size and metastatic status were compared at six cutoff points. @*Results@#A total of 4,525 lymph nodes were examined, 9.1% of which were metastatic. The mean size of the metastatic nodes (long axis, 6.9±5.0 mm; short axis, 4.3±3.1 mm) was significantly larger than that of the non-metastatic nodes (long axis, 5.0±4.0 mm; short axis, 3.0±2.0 mm; all p<.001). Using a 10 mm cutoff, the sensitivity, specificity, positive predictive value, overall accuracy, and area under curve was 24.8%, 88.0%, 17.1%, 82.3%, and 0.60 for the long axis and 7.0%, 99.0%, 40.3%, 90.6%, and 0.61 for the short axis, respectively. @*Conclusions@#The metastatic nodes are larger than the non-metastatic nodes in PDAC patients. However, the difference in nodal size was too small to be identified with preoperative imaging. The performance of preoperative radiologic imaging to predict lymph nodal metastasis was not good. Therefore, nodal size cannot be used a surrogate preoperative marker of lymph node metastasis.

Prognostic Predictability of American Joint Committee on Cancer 8th Staging System for Perihilar Cholangiocarcinoma: Limited Improvement Compared with the 7th Staging System / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study was conducted to evaluate the prognostic values of the 7th and 8th American Joint Committee on Cancer (AJCC) staging systems for patients with resected perihilar cholangiocarcinoma (PHCC). @*Materials and Methods@#A total of 348 patients who underwent major hepatectomy for PHCC between 2008 and 2015 were identified from a single center. Overall survival (OS) was estimated using the Kaplan-Meier method and compared across stage groups with the log-rank test. The concordance index was used to evaluate the prognostic predictability of the 8th AJCC staging system compared with that of the 7th. @*Results@#In the 8th edition, the stratification of each group of T classification improved compared to that in the 7th, as the survival rate of T4 decreased (T2, 31.2%; T3, 13.9%; T4, 15.1%; T1- T2, p=0.260; T2-T3, p=0.001; T3-T4, p=0.996). Both editions showed significant survival differences between each N category, except between N1 and N2 (p=0.063) in 7th edition. Differences of point estimates between the 8th and 7th T and N classification and overall stages were +0.028, +0.006, and +0.039, respectively (T, p=0.005; N, p=0.115; overall stage, p=0.005). In multivariable analysis, posthepatectomy liver failure, T category, N category, distant metastasis, histologic differentiation, intraoperative transfusion, and resection margin status were associated with OS. @*Conclusion@#The prognostic predictability of 8th AJCC staging for PHCC improved slightly, with statistical significance, compared to the 7th edition, but its overall performance is still unsatisfactory.

Efficacy and Safety of Pembrolizumab in Patients with RefractoryAdvanced Biliary Tract Cancer: Tumor Proportion Score as a PotentialBiomarker for Response / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The current standard chemotherapy for advanced biliary tract cancer (BTC) has limited benefit,and novel therapies need to be investigated. @*Materials and Methods@#In this prospective cohort study, programmed death ligand-1 (PD-L1)–positive BTC patientswho progressed on first-line gemcitabine plus cisplatin were enrolled. Pembrolizumab 200mg was administered intravenously every 3 weeks. @*Results@#Between May 2018 and February 2019, 40 patients were enrolled. Pembrolizumab wasgiven as second-line (47.5%) or  third-line therapy (52.5%). The objective response ratewas 10% and 12.5% by Response Evaluation Criteria in Solid Tumor (RECIST) v1.1 andimmune-modified RECIST (imRECIST) and median duration of response was 6.3 months.Among patients with progressive disease as best response, one patient (1/20, 5.0%)achieved complete response subsequently. The median progression-free survival (PFS) andoverall survival (OS) were 1.5 months (95% confidence interval [CI], 0.0 to 3.0) and 4.3months (95% CI, 3.5 to 5.1), respectively, and objective response per imRECIST was significantlyassociated with PFS (p < 0.001) and OS (p=0.001). Tumor proportion score  50%was significantly associated with higher response rates including the response after pseudoprogression(vs. < 50%; 37.5% vs. 6.5%; p=0.049). @*Conclusion@#Pembrolizumab showed modest anti-tumor activity in heavily pretreated PD-L1–positiveBTC patients. In patients who showed objective response, durable response could beachieved.

Predictors of early recurrence following a curative resection in patients with a carcinoma of the ampulla of Vater

Purpose@#Ampulla of Vater (AoV) carcinoma has a relatively good prognosis. The 5-year recurrence rate for AoV is still around 40%–50% however, and most recurrences occur in the early period. The aim of this study was to identify predictors of an early recurrence in AoV patients following a curative resection. @*Methods@#The clinicopathological data for 501 consecutive patients that underwent a resection for AoV in our institute between January 2000 and December 2015 were retrospectively reviewed. The characteristics of any recurrences and early recurrence patients were analyzed accordingly. Early recurrence was defined as occurring within one year of resection. @*Results@#There were 170 diagnosed recurrences in our study population, 57.1% of whom were men, with a mean age of 60.1 years (range, 30–94 years). Almost all of the study patients underwent a pancreaticoduodenectomy, and 9% underwent minimally invasive surgery. Of the 170 recurrent cases, 107 were diagnosed with an early recurrence and had 1-, 3-, and 5-year overall survival rates of 77.7%, 18.4%, 10.5%, respectively. The factors that significantly influenced early recurrences, determined by multivariate analysis, lymphovascular invasion (LVI), lymph node ratio (LNR), and poor differentiation were found to be independent determinants of a recurrence within 1 year. @*Conclusion@#An early recurrence in AoV patients is ultimately lethal even though this cancer has a good prognosis. LVI, LNR, and poor differentiation are powerful predictors of an early recurrence in AoV. Hence, intensive surveillance and new therapeutic strategies should be considered for AoV patients with these predictors following a curative resection.

Coexisting Mucinous Cystic Neoplasm of the Pancreas and Type 1 Autoimmune Pancreatitis

Type 1 autoimmune pancreatitis (AIP1) is an IgG4-related systemic disease that mimics tumors. We report a rare case of AIP1 accompanied by mucinous cystic neoplasm (MCN). A pancreatic lesion was incidentally detected in a woman in her 60s. After 6 years of follow-up, the lesion abruptly increased in size. Computed tomography showed a 3.5 cm unilocular cyst in the tail of the pancreas and distal pancreatectomy was performed. On microscopic examination, the cyst was lined by mucinous and non-mucinous epithelial cells with mild cytologic atypia. The surrounding stroma comprised ovarian-type spindle cells with progesterone receptor positivity. The pericystic pancreas exhibited multifocal lymphoid follicles, lymphoplasmacytic infiltrations, obliterative phlebitis, and storiform fibrosis. IgG4-positive plasma cell infiltration (215 cells high-power field) and the IgG4/IgG ratio (57%) were increased. Cases of MCN coexisting with AIP1 are extremely rare; only two such cases have been reported in the English-language literature. This third case featured low-grade MCN with AIP1.

Validation of the 8th AJCC Cancer Staging System for Pancreas Neuroendocrine Tumors Using Korean Nationwide Surgery Database / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic neuroendocrine tumor (PNET) included several significant changes. We aim to evaluate this staging system compared to the 7th edition AJCC staging system and European Neuroendocrine Tumors Society (ENETS) system. MATERIALS AND METHODS: We used Korean nationwide surgery database (2000-2014). Of 972 patients who had undergone surgery for PNET, excluding patients diagnosed with ENETS/World Health Organization 2010 grade 3 (G3), only 472 patients with accurate stage were included. RESULTS: Poor discrimination in overall survival rate (OSR) was noted between AJCC 8th stage III and IV (p=0.180). The disease-free survival (DFS) curves of 8th AJCC classification were well separated between all stages. Compared with stage I, the hazard ratio of II, III, and IV was 3.808, 13.928, and 30.618, respectively (p=0.007, p < 0.001, and p < 0.001). The curves of OSR and DFS of certain prognostic group in AJCC 7th and ENETS overlapped. In ENETS staging system, no significant difference in DFS between stage IIB versus IIIA (p=0.909) and IIIA versus IIIB (p=0.291). In multivariable analysis, lymphovascular invasion (p=0.002), perineural invasion (p=0.003), and grade (p < 0.001) were identified as independent prognostic factors for DFS. CONCLUSION: This is the first large-scale validation of the AJCC 8th edition staging system for PNET. The revised 8th system provides better discrimination compared to that of the 7th edition and ENETS TNM system. This supports the clinical use of the system.

Prognosis of Pancreatic Cancer Patients with Synchronous or Metachronous Malignancies from Other Organs Is Better than Those with Pancreatic Cancer Only / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Pancreatic cancer associated double primary tumors are rare and their clinicopathologic characteristics are not well elucidated. MATERIALS AND METHODS: Clinicopathologic factors of 1,352 primary pancreatic cancers with or without associated double primary tumors were evaluated. RESULTS: Of resected primary pancreatic cancers, 113 (8.4%) had associated double primary tumors, including 26 stomach, 25 colorectal, 18 lung, and 13 thyroid cancers. The median interval between the diagnoses of pancreatic cancer and associated double primary tumors was 0.5 months. Overall survival (OS) of pancreatic cancer patients with associated double primary tumors was longer than those with pancreatic cancer only (median, 23.1 months vs. 17.0 months; p=0.002). Patients whose pancreatic cancers were resected before the diagnosis of metachronous tumors had a better OS than patients whose pancreatic cancer resected after the diagnosis of metachronous tumors (48.9 months and 13.5 months, p=0.001) or those whose pancreatic cancers were resected synchronously with non-pancreas tumors (19.1 months, p=0.043). The OS of pancreatic cancer patients with stomach (33.9 months, p=0.032) and thyroid (117.8 months, p=0.049) cancers was significantly better than those with pancreas cancer only (17.0 months). CONCLUSION: About 8% of resected pancreatic cancers had associated double primary tumors, and those from the colorectum, stomach, lung, and thyroid were common. Patients whose pancreatic cancer was resected before the diagnosis of metachronous tumors had better OS than those resected after the diagnosis of metachronous tumors or those resected synchronously.

Transduodenal ampullectomy for ampullary tumors - single center experience of consecutive 26 patients

PURPOSE: Transduodenal ampullectomy (TDA) has been reported in a limited number of cases and in a small number of case series. The aim of this study was to analyze perioperative and long-term oncological outcomes of patients with ampullary tumors who underwent TDA in a single large-volume center. METHODS: Through a retrospective review of data from 2004 to 2016, we identified 26 patients who underwent TDA at Asan Medical Center. RESULTS: Eleven of 26 patients underwent TDA for T1 and carcinoma in situ (high-grade dysplasia) cancer; these patients are still alive without recurrence. A major in-hospital complication (3.8%) occurred in 1 case, but there was no case of 90-day mortality. In addition, none of the patients was diagnosed as having newly developed diabetes mellitus after TDA. No significant differences were found between open and laparoscopic-TDA in terms of operation time, painkiller use, and hospital stay. CONCLUSION: TDA is a feasible and effective surgical procedure for the treatment of selected patients with ampullary tumors. It is an alternative treatment option in cases of ampullary tumors not amenable to endoscopic papillectomy or pancreaticoduodenectomy.

In Vivo Observation of Endothelial Cell-Assisted Vascularization in Pancreatic Cancer Xenograft Engineering

In this study, for better understanding of patient-derived xenograft (PDX) generation, angiogenic characteristics during PDX cancerous tissue generation was investigated with different initial cell seeding conditions in the hydrogel. We monitored the angiogenic changes during the formation of in vivo cancer cell line xenografts induced by endothelial cells. Our in vivo cancer tissue formation system was designed with the assistance of tissue engineering technology to mimic patient-derived xenograft formation. Endothelial cells and MIA PaCa-2 pancreatic carcinoma cells were encapsulated in fibrin gel at different mixing configurations and subcutaneously implanted into nude mice. To investigate the effect of the initial cancerous cell distribution in the fibrin gel, MIA PaCa-2 cells were encapsulated as a homogeneous cell distribution or as a cell aggregate, with endothelial cells homogeneously distributed in the fibrin gel. Histological observation of the explanted tissues after different implantation periods revealed three different stages: isolated vascular tubes, leaky blood vessels, and mature cancerous tissue formation. The in vivo engineered cancerous tissues had leaky blood vessels with low expression of the vascular tight junction marker CD31. Under our experimental conditions, complex cancer-like tissue formation was most successful when tumorous cells and endothelial cells were homogeneously mixed in the fibrin gel. The present study implies that tumorous xenograft tissue formation can be achieved with a low number of initial cells and that effective vascularization conditions can be attained with a limited volume of patient-derived cancer tissue. Endothelial cell-assisted vascularization can be a potent choice for the effective development of vascularized cancerous tissues for studying patient-derived xenografts, cancer angiogenesis, cancer metastasis, and anticancer drugs.

Loss of Progesterone Receptor Expression Is an Early Tumorigenesis Event Associated with Tumor Progression and Shorter Survival in Pancreatic Neuroendocrine Tumor Patients

BACKGROUND: Pancreatic neuroendocrine tumors (PanNETs) are the second most common pancreatic neoplasms and there is no well-elucidated biomarker to stratify their detection and prognosis. Previous studies have reported that progesterone receptor (PR) expression status was associated with poorer survival in PanNET patients. METHODS: To validate previous studies, PR protein expression was assessed in 21 neuroendocrine microadenomas and 277 PanNETs and compared with clinicopathologic factors including patient survival. RESULTS: PR expression was gradually decreased from normal islets (49/49 cases, 100%) to neuroendocrine microadenoma (14/21, 66.6%) to PanNETs (60/277, 21.3%; p < .001). PanNETs with loss of PR expression were associated with increased tumor size (p < .001), World Health Organization grade (p = .001), pT classification (p < .001), perineural invasion (p = .028), lymph node metastasis (p = .004), activation of alternative lengthening of telomeres (p = .005), other peptide hormonal expression (p < .001) and ATRX/DAXX expression (p = .015). PanNET patients with loss of PR expression (5-year survival rate, 64.1%) had significantly poorer recurrence-free survival outcomes than those with intact PR expression (90%) by univariate (p = .012) but not multivariate analyses. Similarly, PanNET patients with PR expression loss (5-year survival rate, 76%) had significantly poorer overall survival by univariate (p = .015) but not multivariate analyses. CONCLUSIONS: Loss of PR expression was noted in neuroendocrine microadenomas and was observed in the majority of PanNETs. This was associated with increased grade, tumor size, and advanced pT and pN classification; and was correlated with decreased patient survival time by univariate but not multivariate analyses. Loss of PR expression can provide additional information on shorter disease-free survival in PanNET patients.

CTHRC1 promotes angiogenesis by recruiting Tie2-expressing monocytes to pancreatic tumors

CTHRC1 (collagen triple-helix repeat-containing 1), a protein secreted during the tissue-repair process, is highly expressed in several malignant tumors, including pancreatic cancer. We recently showed that CTHRC1 has an important role in the progression and metastasis of pancreatic cancer. Although CTHRC1 secretion affects tumor cells, how it promotes tumorigenesis in the context of the microenvironment is largely unknown. Here we identified a novel role of CTHRC1 as a potent endothelial activator that promotes angiogenesis by recruiting bone marrow-derived cells to the tumor microenvironment during tumorigenesis. Recombinant CTHRC1 (rCTHRC1) enhanced endothelial cell (EC) proliferation, migration and capillary-like tube formation, which was consistent with the observed increases in neovascularization in vivo. Moreover, rCTHRC1 upregulated angiopoietin-2 (Ang-2), a Tie2 receptor ligand, through ERK-dependent activation of AP-1 in ECs, resulting in recruitment of Tie2-expressing monocytes (TEMs) to CTHRC1-overexpressing tumor tissues. Treatment with a CTHRC1-neutralizing antibody-abrogated Ang-2 expression in the ECs in vitro. Moreover, administration of a CTHRC1-neutralizing antibody to a xenograft mouse model reduced the tumor burden and infiltration of TEMs in the tumor tissues, indicating that blocking the CTHRC1/Ang-2/TEM axis during angiogenesis inhibits tumorigenesis. Collectively, our findings support the hypothesis that CTHRC1 induction of the Ang-2/Tie2 axis mediates the recruitment of TEMs, which are important for tumorigenesis and can be targeted to achieve effective antitumor responses in pancreatic cancers.

Clinical and Prognostic Significances of Cytokeratin 19 and KIT Expression in Surgically Resectable Pancreatic Neuroendocrine Tumors

BACKGROUND: Pancreatic neuroendocrine tumors (PanNETs) are malignant endocrine neoplasms that present diverse clinical behaviors. Therefore, identification of biomarkers of PanNETs is important for stratification of the prognosis of PanNET patients. Recently, cytokeratin 19 (CK19) and KIT expression were reported to have prognostic significance in PanNET patients. METHODS: To identify their prognostic significance, CK19 and KIT protein expression were assessed in 182 surgically resected PanNETs and compared with clinicopathologic factors. RESULTS: Of 182 PanNETs cases, CK19 and KIT expression was noted in 97 (53.3%) and 16 (8.8%) cases, respectively. PanNET patients with CK19 expression had larger tumors (p=.006), higher World Health Organization (WHO) grade (p=.002) and pT classification (p<.001), increased distant metastasis (p=.004), and lymphovascular (p=.012) and perineural (p=.019) invasion. Similarly, those with KIT expression had larger tumors (p=.030), higher WHO grade (p=.001), advanced pT classification (p<.001), distant metastasis (p=.001), and lymphovascular invasion (p=.014). The 5-year survival rate for PanNET patients with KIT expression was significantly lower (62%) than that of patients without KIT expression (77%, p=.011), as determined by univariate but not by multivariate analyses. CONCLUSIONS: CK19 and KIT expression correlate with higher metastatic potential and advanced disease stage, and KIT expression is associated with worse survival in PanNET patients.

Branch duct intraductal papillary mucinous neoplasm of the pancreas: single-center experience with 324 patients who underwent surgical resection

BACKGROUNDS/AIMS: International treatment guidelines for branch duct intraductal papillary mucinous neoplasm (BD-IPMN) of the pancreas have been proposed, for features associated with malignancy and invasiveness. We investigated the clinicopathological characteristics that are predictive of malignancy or invasiveness and disease recurrence. METHODS: A review of 324 patients with resected and pathologically confirmed BD-IPMN, between March 1997 and December 2013, was conducted. RESULTS: There were 144 (44.4%) low grade dysplasia (LGD), 138 (42.6%) intermediate grade dysplasia (IMGD), 17 (5.3%) high grade dysplasia (HGD), and 25 (7.7%) invasive carcinoma (invIPMC) cases. The 5-year survival rates were 98.1% for LGD, 95.3% for IMGD, 100% for HGD, and 71.8% for invIPMC. Through a univariate analysis, the male sex was associated with malignancy, and CA19-9 was related to both malignant and invasive IPMN. The high risk or worrisome features of the international guidelines were associated with both malignant and invasive IPMN: the total bilirubin of the head/uncinate lesion, tumor size, mural nodule, and the size of the main pancreatic duct (MPD). Through a multivariate analysis, the male sex, elevated CA19-9, mural nodule, and dilated MPD diameter were independently correlated with the malignant IPMN. The elevated CA19-9 and dilated MPD diameter were also correlated with invasive carcinoma. The patient age and the initial pathological diagnosis were strongly associated with disease recurrence following surgical resection. CONCLUSIONS: The high risk or worrisome features in the current treatment guidelines for BD-IPMN are confined to the morphological characteristics of the disease. Patient factors and biological features should also be considered in order to develop optimal therapeutic or surveillance strategies.

Prognostic factors associated with early mortality after surgical resection for pancreatic adenocarcinoma

BACKGROUNDS/AIMS: Identifying pancreatic cancer patients at high risk of early mortality following surgical resection for pancreatic cancer is important to make optimal treatment decisions in multidisciplinary setting. The purpose of this study was to identify the factors related to early mortality in patients who underwent pancreatic resection for pancreatic adenocarcinoma. METHODS: We reviewed our institution's experience with all consecutive patients who underwent pancreatectomy for pancreatic adenocarcinoma from January 2000 to December 2010. One thousand patients were eligible for our study. Fifty-three patients who did not meet the study criteria were excluded. Based on 12 months after surgery, patients were divided into early mortality group or the remaining group. We performed logistic regression analysis to identify predictors of early mortality. RESULTS: Among 947 patients who met our study criteria, 302 (31.9%) early mortality (defined as experiencing death within 12 months after surgery) occurred. Multivariate analysis revealed that patient age and surgery time period were statistically significant predictors of early mortality within six months after surgery. Poorly differentiated tumor and adjuvant chemotherapy were statistically significant predictors of early mortality within 12 months after surgery. Total pancreatectomy and lymphovascular invasion were significant (p<0.05) prognostic factors of early mortality within 6 or 12 months after surgery. CONCLUSIONS: We suggest followings to avoid early mortality after pancreatic resection: patients with multiple risk factors related to early mortality after pancreatectomy should be considered for alternative treatment; patient's general condition and surgical technique improvement are important; and adjuvant therapy should be taken into consideration.