[A Case of Synchronous Solitary Splenic Metastasis of Sigmoid Colon Cancer Treated with Laparoscopic Resection].

An 82-year-old woman presented to our hospital with chief complaints of lower abdominal pain and nausea. Contrast- enhanced CT showed ileus of sigmoid colon cancer and a solitary splenic tumor. A metallic stent was placed for the primary lesion. FDG-PET showed high FDG accumulation in the solitary splenic tumor, and synchronous solitary splenic metastasis was diagnosed. Laparoscopic sigmoid colectomy and laparoscopic splenectomy were performed without changing the intraoperative position or port arrangement. Postoperative progress was favorable. The patient was discharged 9 days after surgery, and no sign of recurrence has been observed to date, at 4 months after surgery. Solitary splenic metastasis of colorectal cancer is extremely rare. This is the first case report of synchronous solitary splenic metastasis of colorectal cancer treated with laparoscopic resection in Japan. This procedure is considered effective and minimally invasive. We review and discuss the Japanese literature on this rare disease.

Loss of ARID1A induces a stemness gene ALDH1A1 expression with histone acetylation in the malignant subtype of cholangiocarcinoma.

Genomic analyses have recently discovered the malignant subtype of human intrahepatic cholangiocarcinoma (ICC) characterized by frequent mutations of chromatin remodeling gene ARID1A; however, the biological and molecular functions still remain obscure. We here examined the clinical and biological significances of ARID1A deficiency in human ICC. Immunohistochemical analysis demonstrated that the loss of ARID1A was an independent prognostic factor for overall survival of ICC patients (P = 0.023). We established ARID1A-knockout (KO) cells by using the CRISPR/Cas9 system from two human cholangiocarcinoma cell lines. ARID1A-KO cells exhibited significantly enhanced migration, invasion, and sphere formation activity. Microarray analysis revealed that ALDH1A1, a stemness gene, was the most significantly elevated genes in ARID1A-KO cells. In addition, ALDH enzymatic activity as a hallmark of cancer stem cells was markedly high in the KO cells. ARID1A and histone deacetylase 1 were directly recruited to the ALDH1A1 promoter region in cholangiocarcinoma cells with undetectable ALDH1A1 expression by chromatin immunoprecipitation assay. The histone H3K27 acetylation level at the ALDH1A1 promoter region was increased in cells when ARID1A was disrupted (P < 0.01). Clinically, inverse correlation between ARID1A and ALDH1A1 expression was also identified in primary ICC (P = 0.018), and ARID1A-negative and ALDH1A1-positve ICCs showed worse prognosis than only ARID1A-negative cases (P = 0.002). In conclusion, ARID1A may function as a tumor suppressor in ICC through transcriptional downregulation of ALDH1A1 expression with decreasing histone H3K27 acetylation. Our studies provide the basis for the development of new epigenetic approaches to ARID1A-negative ICC. Immunohistochemical loss of ARID1A is an independent prognostic factor in intrahepatic cholangiocarcinoma patients. ARID1A recruits HDAC1 to the promoter region of ALDH1A1, a stemness gene, and epigenetically suppresses ALDH1A1 expression with decreasing histone H3K27 acetylation in cholangiocarcinoma cells.

Downregulated Pancreatic Beta Cell Genes Indicate Poor Prognosis in Patients With Pancreatic Neuroendocrine Neoplasms.

OBJECTIVE: To predict metachronous liver metastasis after pancreatectomy for pancreatic neuroendocrine neoplasms (Pan-NENs). SUMMARY OF BACKGROUND DATA: Liver metastasis determines the prognosis of patients with Pan-NENs, but no index exists in the WHO 2017 classification for this prediction. METHODS: Between April 2014 and March 2018, resected primary tumors from 20 patients with or without simultaneous liver metastasis were examined using genome-wide gene expression analysis. For validation analysis, resected primary tumors from 62 patients without simultaneous liver metastasis were examined for PAX6 expression. RESULTS: Gene expression profiling revealed pancreatic beta cell genes (NES, -2.0; P < 0.001) as the most downregulated set in patients with simultaneous liver metastasis. In the test study, PAX6 was the most valuable index for liver metastasis (log FC, -3.683; P = 0.0096). Multivariate analysis identified PAX6 expression (hazard ratio, 0.2; P = 0.03) as an independent risk factor for metachronous liver metastasis-free survival (mLM-FS). The 5-year mLM-FS of patients with high versus low PAX6 expression was significantly better (95% vs 66%, respectively; P < 0.0001). The 5-year overall survival rate of was also better than in those with high versus low PAX6 expression (100% vs 87%, respectively). Patients with low PAX 6 expression were significantly younger and leaner, had a higher Ki-67 index (P = 0.01, 0.007, 0.008, respectively), and showed a higher mitotic rate than patients with high PAX6 expression. CONCLUSIONS: Downregulated pancreatic beta cell genes involving PAX6 in primary tumors may predict mLM and poor overall survival after primary tumor resection in Pan-NEN patients.

Position of the Pancreas Division Line and Postoperative Outcomes After Distal Pancreatectomy.

BACKGROUND: In distal pancreatectomy (DP), the position of the pancreas division line (PDL) changes depending on the location or nature of the tumor. Here, we investigated the relationship between PDL and postoperative complications after DP. METHODS: We retrospectively analyzed data of 140 patients who underwent DP at Tokyo Medical and Dental University Hospital between January 2011 and September 2018. PDL was defined as the distance from the left margin of the portal vein to the edge of the pancreatic stump on the coronal plane of computed tomography. RESULTS: The mean PDL was 15.1 (range 0-74.3) mm. PDL was significantly longer in patients with portal venous system thrombosis (PVST) than in those without PVST (47.6 vs. 0 mm, p < 0.001). The PDLlong (≥ 20 mm) group underwent surgery with a significantly shorter duration (253 vs. 294 min, p < 0.001) and experienced a lower volume of blood loss (20 vs. 256.5 mL, p < 0.001) than the PDLshort (< 20 mm) group. Six months after surgery, the increase in HbA1c level was significantly higher in the PDLshort group than in the PDLlong group (0.5 vs. 0.35%, p = 0.041). Except for PVST, there was no significant difference in postoperative complications between the two groups. CONCLUSIONS: In DP, pancreas resection with a longer PDL resulted in a significantly shorter duration of surgery, lower estimated blood loss, and superior glucose tolerance than that with a shorter PDL.

Loss of KDM6A characterizes a poor prognostic subtype of human pancreatic cancer and potentiates HDAC inhibitor lethality.

Although genomic analysis have recently discovered the malignant subtype of human pancreatic ductal adenocarcinoma (PDAC) characterized by frequent mutations of histone demethylase KDM6A, the biological and molecular roles still remain obscure. We herein elucidated the clinical and biological impacts of KDM6A deficiency on human PDAC and identified the therapeutic potential by pathological and molecular evaluation. Immunohistochemical analysis suggested that loss of KDM6A in cancerous tissues was an independent prognostic factor for both recurrence-free and overall survival in the 103 tumor specimens surgically resected from patients with PDAC. We established KDM6A knocked out cells by using the CRISPR/Cas9 system and KDM6A-expressed cells by doxycycline-inducible system from each two human PDAC cell lines, respectively. KDM6A knockout enhanced aggressive traits of human PDAC cell lines, whereas KDM6A overexpression suppressed them. Microarray analysis revealed reduced expression of 22 genes including five well-known tumor suppressors, such as CDKN1A, and ChIP-PCR analysis displayed depleted enrichment of histone H3 lysine 27 acetylation (H3K27ac) at the promoter regions of the five candidates. The epigenetic alterations were induced by the impaired recruitment of histone acetyltransferase p300, which cooperatively interacted with KDM6A. Consistent with these results, the KDM6A knockout cells demonstrated higher vulnerability to histone deacetylase (HDAC) inhibitors through the reactivation of CDKN1A in vitro and in vivo than the KDM6A wild-type. In conclusion, KDM6A exhibited essential roles in human PDAC as a tumor suppressor and KDM6A deficiency could be a promising biomarker for unfavorable outcome in PDAC patients and a potential surrogate marker for response to HDAC inhibitors.

Fatty Acid Binding Protein 4 (FABP4) Overexpression in Intratumoral Hepatic Stellate Cells within Hepatocellular Carcinoma with Metabolic Risk Factors.

Metabolic syndrome is a newly identified risk factor for hepatocellular carcinoma (HCC); however, tumor-specific biomarkers still remain unclear. We performed cross-species analysis to compare gene signatures of HCC from human patients and melanocortin 4 receptor-knockout mice, which develop HCC with obesity, insulin resistance, and dyslipidemia. Unsupervised hierarchical clustering and principle component analysis of 746 differentially expressed orthologous genes classified HCC of 152 human patients and melanocortin 4 receptor-knockout mice into two distinct subgroups, one of which included mouse HCC and was causatively associated with metabolic risk factors. Nine genes commonly overexpressed in human and mouse metabolic disease-associated HCC were identified; fatty acid binding protein 4 (FABP4) was remarkably enriched in intratumoral activated hepatic stellate cells (HSCs). Subclones constitutively expressing FABP4 were established from a human HSC cell line in which expression levels of inflammatory chemokines, including IL-1A and IL-6, were up-regulated through NF-κB nuclear translocation, resulting in recruitment of macrophages. An immunohistochemical validation study of 106 additional human HCC samples indicated that FABP4-positive HSCs were distributed in tumors of 38 cases, and the FABP4-high group consisted of patients with nonviral and nonalcoholic HCC (P = 0.027) and with multiple metabolic risk factors (P < 0.001) compared with the FABP4-low group. Thus, FABP4 overexpression in HSCs may contribute to hepatocarcinogenesis in patients with metabolic risk factors by modulation of inflammatory pathways.

Orotate phosphoribosyltransferase as a predictor of benefit from S-1 adjuvant chemotherapy for cholangiocarcinoma patients.

BACKGROUND AND AIM: To improve the prognosis of cholangiocarcinoma, we investigated potential biomarkers that may enable the selection of patients for whom postoperative adjuvant chemotherapy is likely effective. METHODS: The cohort of this retrospective study included 170 surgically resected cholangiocarcinoma patients, 26 with gemcitabine adjuvant chemotherapy (GEM group), 36 with S-1 adjuvant chemotherapy (S-1 group), and 103 receiving no adjuvant chemotherapy (NC group). Propensity score matching was performed to adjust patient backgrounds; 36 patients from the NC group then were selected. Immunohistochemistry of orotate phosphoribosyltransferase (OPRT) and human equilibrative nucleoside transporter 1 (hENT1) was performed to determine the correlation between their expression and disease-free survival (DFS). RESULTS: After matching, the backgrounds of these three groups were unbiased. No significant improvement of DFS by adjuvant chemotherapy was observed in the whole cohort. However, among the high-OPRT-expression patients, DFS of GEM, S-1, and NC groups at 5 years was 28.8%, 53.8%, and 25.5%, respectively. The DFS of the S-1 group was significantly longer than that of the NC group (P = 0.034). On the other hand, no significant differences in DFS were observed among the low OPRT expression patients. hENT1 expression was shown to have no predictive value. Multivariate analysis of the high-OPRT-expression patients demonstrated that S-1 adjuvant chemotherapy can reduce tumor recurrence (HR, 0.303; P = 0.013). CONCLUSION: Cholangiocarcinoma patients with high OPRT expression would benefit from postoperative adjuvant S-1 therapy, which increases the DFS. Assessment of OPRT expression may contribute to the optimization of adjuvant chemotherapy for cholangiocarcinoma.

The Clinical Implications of Peripancreatic Fluid Collection After Distal Pancreatectomy.

OBJECTIVES: Pancreatic fistula after distal pancreatectomy (DP) remains an unsolved problem, and postoperative CT imaging often demonstrates fluid collection (FC) around the pancreatic remnant. This study sought to clarify the clinical implications of FC. METHODS: This study enrolled 146 patients who underwent DP. FC was defined as a cyst-like lesion ≥ 10 mm in diameter on CT imaging at postoperative day (POD) 7. FC size, irregularity of FC margin, and air bubbles in FC were investigated. In addition, clinical data were retrospectively collected, and useful predictive factors for postoperative pancreatic fistula (POPF) were analyzed. RESULTS: Clinically relevant POPF was observed in 26 patients (17.8%), and FC was detected in 136 patients (94.4%). Multivariate analysis identified FC size and drain amylase levels on POD3 as significant risk factors for POPF. Cutoff values were determined by ROC analyses, and the levels of the FC size and drain amylase on POD3 were determined as 41 mm and 1026 IU/L, respectively. The sensitivity and specificity of FC diameters > 41 mm were 76.9% and 75.0%, respectively, while those of drain amylase levels > 1026 IU on POD3 were 73.1% and 75.8%, respectively. CONCLUSIONS: While treating some FCs after DP was necessary for the management of POPF, others did not require any intervention since most of them spontaneously disappeared. FC size and drain amylase levels on POD3 were found to be significantly associated with POPF and could potentially help to determine appropriate treatment.

ARID2 modulates DNA damage response in human hepatocellular carcinoma cells.

BACKGROUND & AIMS: Recent genomic studies have identified frequent mutations of AT-rich interactive domain 2 (ARID2) in hepatocellular carcinoma (HCC), but it is not still understood how ARID2 exhibits tumor suppressor activities. METHODS: We established the ARID2 knockout human HCC cell lines by using CRISPR/Cas9 system, and investigated the gene expression profiles and biological functions. RESULTS: Bioinformatic analysis indicated that UV-response genes were negatively regulated in the ARID2 knockout cells, and they were sensitized to UV irradiation. ARID2 depletion attenuated nucleotide excision repair (NER) of DNA damage sites introduced by exposure to UV as well as chemical compounds known as carcinogens for HCC, benzo[a]pyrene and FeCl3, since xeroderma pigmentosum complementation group G (XPG) could not accumulate without ARID2. By using large-scale public data sets, we validated that ARID2 knockout could lead to similar molecular changes between in vitro and in vivo settings. A higher number of somatic mutations in the ARID2-mutated subtypes than that in the ARID2 wild-type across various types of cancers including HCC was observed. CONCLUSIONS: We provide evidence that ARID2 knockout could contribute to disruption of NER process through inhibiting the recruitment of XPG, resulting in susceptibility to carcinogens and potential hypermutation. These findings have implications for therapeutic targets in cancers harboring ARID2 mutations. LAY SUMMARY: Recent genomic studies have identified frequent mutations of ARID2, a component of the SWItch/Sucrose Non-Fermentable (SWI/SNF) complex, in hepatocellular carcinoma, but it is not still understood how ARID2 exhibits tumor suppressor activities. In current study, we provided evidence that ARID2 knockout could contribute to disruption of DNA repair process, resulting in susceptibility to carcinogens and potential hypermutation. These findings have far-reaching implications for therapeutic targets in cancers harboring ARID2 mutations.

Novel Aurora/vascular endothelial growth factor receptor dual kinase inhibitor as treatment for hepatocellular carcinoma.

We previously identified Aurora B kinase as the only independent factor predictive of the aggressive recurrence of hepatocellular carcinoma (HCC). In this preclinical study, JNJ-28841072, a novel Aurora/vascular endothelial growth factor receptor dual kinase inhibitor, was evaluated for treatment of HCC. In vitro and in vivo effects of JNJ-28841072 were analyzed using human HCC cell cultures and xenograft models. An orthotopic liver xenograft model was used for the pharmacobiological effects on Aurora kinase and vascularization in hepatic tumors. JNJ-28841072 suppressed in vitro phosphorylation of histone H3 with induction of cell polyploidy and death in a dose-dependent manner (IC50  = 0.8-1.2 µM). In s.c. human HCC xenografts, remarkable inhibition of tumor growth was observed after JNJ-28841072 treatment (P = 0.0005). In orthotopic liver xenografts, the treatment with JNJ-28841072 significantly suppressed in vivo phosphorylation of histone H3 (P = 0.0008), vessel formation (P = 0.018), normoxic area (P = 0.0001), and hepatoma growth (P = 0.038). Our preclinical studies indicate that JNJ-28841072 is a promising novel therapeutic approach for the treatment of HCC. It might be worthy of evaluation in further studies.

Contrast-enhanced intraoperative ultrasonography for vascular imaging of hepatocellular carcinoma: clinical and biological significance.

UNLABELLED: Abnormal tumor vascularity is one of the typical features of hepatocellular carcinoma (HCC). In this study, the significance of contrast-enhanced intraoperative ultrasonography (CEIOUS) images of HCC vasculature was evaluated by clinicopathological and gene expression analyses. We enrolled 82 patients who underwent curative hepatic resection for HCC with CEIOUS. Clinicopathological and gene expression analyses were performed according to CEIOUS vasculature patterns. CEIOUS images of HCC vasculatures were classified as reticular HCC or thunderbolt HCC. Thunderbolt HCC was significantly correlated with higher alpha-fetoprotein levels, tumor size, histological differentiation, portal vein invasion, and tumor-node-metastasis stage, and these patients demonstrated a significantly poorer prognosis for both recurrence-free survival (P = 0.0193) and overall survival (P = 0.0362) compared with patients who had reticular HCC. Gene expression analysis revealed that a rereplication inhibitor geminin was significantly overexpressed in thunderbolt HCCs (P = 0.00326). In vitro knockdown of geminin gene reduced significantly the proliferation of human HCC cells. Immunohistochemical analysis confirmed overexpression of geminin protein in thunderbolt HCC (P < 0.0001). Multivariate analysis revealed geminin expression to be an independent factor in predicting poor survival in HCC patients (P = 0.0170). CONCLUSION: CEIOUS vascular patterns were distinctly identifiable by gene expression profiling associated with cellular proliferation of HCC and were significantly related to HCC progression and poor prognosis. These findings might be clinically useful as a determinant factor in the postoperative treatment of HCC.

High resectability of colorectal liver metastases with aggressive chemotherapy in the era of molecular target-based agents.

BACKGROUND/AIMS: Advances in chemotherapy have expanded the resectability of colorectal liver (CRC) metastases. We studied treatment results in CRC patients with liver metastases in the era of molecular target-based agents. METHODOLOGY: Based on data collected retrospectively, we analyzed the demographics, operative and pathological outcomes, and adjuvant chemotherapy, of 91 consecutive CRC patients with liver metastases treated between January, 2008 and June, 2010. RESULTS: Of the 91 patients, 42 (46.2%) underwent liver resection (group 1), 41 underwent only resection of the primary tumor without hepatectomy (group 2), and 8 underwent palliative surgery (group 3). According to multivariate analysis, resection of liver metastases was significantly influenced by the number of metastases and the existence of extrahepatic metastases. Disease-free survival (DFS) differed significantly between patients who received adjuvant therapy and those treated by surgery alone (p<0.001). The regimen (p=0.01) and duration (p<0.0001) of adjuvant chemotherapy also affected DFS. Overall survival after 1 and 3 years was 97.6% and 94.0%, respectively, in group 1, 71.9% and 30.6% in group 2, and 33.3% and 0% in group 3. CONCLUSIONS: Although the observation period was short, our findings suggest that high resectability and effective chemotherapy will prolong the survival of patients with colorectal liver metastases.

Importin-α1 as a novel prognostic target for hepatocellular carcinoma.

BACKGROUND: Perturbations in the nuclear microenvironment, including transport systems, play a critical role in malignant progression, but the nuclear import abnormalities remain unclear in hepatocarcinogenesis. We analyzed the role of importin in hepatocellular carcinoma (HCC). METHODS: Gene expression profiling of the importin family was performed in HCC tissues. The significance of importin protein expression was analyzed in vitro as well as clinicopathologically. RESULTS: According to the microarray profiles, the importin-α1 was dominantly overexpressed in HCC tissues as compared to the adjacent noncancerous tissues. By means of human HCC cell lines, a knockdown of importin-α1 by its siRNA greatly reduced cellular proliferation by 15.2-26.6% (P < 0.005). Immunohistochemical analysis on tissue samples demonstrated cancer-specific overexpression in 36.3% of HCCs. The overexpression of importin-α1 was correlated statistically with high levels of alfa-fetoprotein ( P = 0.0017), the tumor number (P = 0.0116), histological dedifferentiation (P = 0.0054), tumor morphology (P = 0.0433), portal vein invasion (P = 0.0007), hepatic vein invasion (P = 0.0081), Fc (P = 0.0367), Fc-inf (P = 0.0122), and the tumor, node, metastasis stage (P = 0.0026); this resulted in a significantly poorer prognosis in both overall survival (P = 0.0164) and recurrence-free survival (P = 0.0101). Multivariate analysis of recurrence-free survival revealed importin-α1 expression to be a statistically significant factor (P = 0.0361). In addition, early recurrence after curative resection was observed more frequently in the importin-α1-positive group as compared to the negative group (P = 0.0023). The multivariate analysis identified importin-α1 as the only independent predictor of early recurrence after HCC resection (odds ratio = 5.291, P = 0.0191). CONCLUSIONS: Because importin-α1 might be closely associated with HCC progression, further analysis should be pursued to evaluate it as a novel prognostic target.

The selective Aurora B kinase inhibitor AZD1152 as a novel treatment for hepatocellular carcinoma.

BACKGROUND & AIMS: We previously identified that high Aurora B expression was associated with hepatocellular carcinoma (HCC) recurrence due to tumor dissemination. In this preclinical study, a novel inhibitor of Aurora B kinase was evaluated as a treatment for human HCC. METHODS: AZD1152 is a selective inhibitor of Aurora B kinase. Twelve human HCC cell lines were analyzed for Aurora B kinase expression and the in vitro effects of AZD1152. The in vivo effects of AZD1152 were analyzed in a subcutaneous xenograft model and a novel orthotopic liver xenograft model. RESULTS: Aurora B kinase expression varied among the human HCC cell lines and was found to correlate with inhibition of cell proliferation, accumulation of 4N DNA, and the proportion of polyploid cells following administration of AZD1152-hydroxyquinazoline-pyrazol-anilide (AZD1152-HQPA). AZD1152-HQPA suppressed histone H3 phosphorylation and induced cell death in a dose-dependent manner. Growth of subcutaneous human HCC xenografts was inhibited by AZD1152 administration. In an orthotopic hepatoma model, treatment with AZD1152 significantly decelerated tumor growth and increased survival. Pharmacobiological analysis revealed that AZD1152 induced the rapid suppression of phosphohistone H3, followed by cellular apoptosis in the liver tumors but not in the normal tissues of the orthotopic models. CONCLUSIONS: Our preclinical studies indicate that AZD1152 is a promising novel therapeutic approach for the treatment of HCC.

Reticular pattern around superior mesenteric artery in computed tomography imaging predicting poor prognosis of pancreatic head cancer.

BACKGROUND: Some patients with pancreatic ductal adenocarcinoma (PDAC) demonstrate a reticular pattern around the superior mesenteric artery (SMA) in computed tomography scans. This study aimed to clarify the clinical significance of the reticular pattern in pancreatic head cancer. METHODS: A total of 91 patients with pancreatic head cancer, who underwent upfront pancreaticoduodenectomy between 2004 and 2017, were included. Patients without reticular pattern (Non-group, n = 39); with reticular pattern around SMA (Ret-group, n = 39); and with soft tissue contact (Soft-group, n = 13) were compared. RESULTS: Median overall survival (OS) of patients in the Ret-group was significantly worse than that in the Non-group (21.3 vs. 57.0 months; P < 0.001) and equivalent to that in the Soft-group. In the multivariate analysis, reticular pattern and high CA19-9 levels were identified as independent predictors of OS. Microscopically, only fibrotic thickenings were identified corresponding to the reticular pattern areas, and no difference in the frequency of early local recurrence was noted between the Non and Ret-groups. Lymphovascular invasion was significantly different between the two groups; furthermore, early distant recurrence was more frequent in the Ret-group. CONCLUSIONS: The reticular pattern around SMA is an important prognostic factor related to frequent distant recurrence in patients with pancreatic cancer.

Does sunitinib have a patient-specific dose without diminishing its antitumor effect on advanced pancreatic neuroendocrine neoplasms?

PURPOSE: Because it is unknown whether adjusting the dose of sunitinib can benefit patients with pancreatic neuroendocrine neoplasms (Pan-NENs), this retrospective study examined maximum tumor shrinkage rates and prognoses in patients with and without low doses of sunitinib administration. METHODS: Eighty-seven patients with metastatic and unresectable neoplasms, treated with sunitinib for > 1 month, were divided into a low-dose (LD) or high-dose (HD) group. The tumor response rates were investigated over time using computed tomography according to the response evaluation criteria in solid tumors criteria. RESULTS: The LD and HD groups included 42 and 45 patients, respectively. There were no differences in baseline characteristics (tumor size, Ki-67 index, mitosis, and differentiation) between the two groups. Progressive disease (PD), stable disease (SD), and partial response (PR) were observed in 16.7, 54.8, and 28.6% of patients in the LD group, respectively, and in 13.3, 60, and 26.7% of patients in the HD group, respectively. There were no differences in tumor shrinkage rates between the two groups (p = 0.87). The 3-year progression-free survival rates for the LD and HD groups were 2.4% and 2.3%, respectively (p = 0.67), and the 3-year overall survival rates were 57.9% and 70.5%, respectively (p = 0.76). The occurrence of adverse events was similar between the two groups (61.9% vs. 60.0%, p > 0.95). CONCLUSIONS: Dose reduction of sunitinib did not alter tumor shrinkage rates or prognoses for patients with advanced Pan-NENs.

Splenic artery as a simple landmark indicating difficulty during laparoscopic distal pancreatectomy.

INTRODUCTION: The use of laparoscopic distal pancreatectomy (LDP) is increasing worldwide. It is important for surgeons to predict preoperatively the difficulty and risks of a surgery. However, very few reports have evaluated the impact of patient or tumor factors on the difficulty of LDP. We aimed to determine the predictors of technical difficulties when performing LDP. METHODS: This study included 34 patients who underwent LDP. Patient information was obtained retrospectively and included age, gender, BMI, primary disease, previous abdominal surgery, previous pancreatitis, tumor size, tumor proximity to the splenic arterial origin, type of splenic artery (SpA), operative time, blood loss, postoperative pancreatic fistula, and length of hospital stay. Univariate and multivariate analyses were performed to determine the predictors of a long operative time. SpA anatomy was classified into two types based on the relationship between its origin and the pancreas. Patients whose SpA origin was upward of the pancreatic parenchyma were classified as SpA type 1, whereas patients whose SpA origin was covered by the pancreatic parenchyma were classified as SpA type 2. RESULTS: Multivariate analysis revealed SpA type 2 to be an independent risk factor for a long operation (odds ratio = 9.925; 95% confidence interval: 1.461-67.412; P = 0.019). SpA type 2 was related to a longer operative time (P < 0.001) and greater intraoperative blood loss (P = 0.001). CONCLUSION: Classification according to SpA type is simple and useful for predicting technical difficulty when performing LDP.

A simple and practical index predicting the prognoses of the patients with well-differentiated pancreatic neuroendocrine neoplasms.

BACKGROUND: The prognostic importance of the neuroendocrine (NE) markers involving neural cell adhesion molecule (NCAM) has been unclear enough to be adopted for WHO classification in patients with pancreatic neuroendocrine neoplasms (Pan-NENs). This study aimed to elucidate whether the three NE markers such as chromogranin A, synaptophysin, and NCAM decide prognoses for patients with well-differentiated tumors. METHODS: Between April 2002 and October 2018, 217 patients were included in this study. Tissue samples from tumors of Pan-NENs were immunochemically stained for the aforementioned NE markers. Diffuse and intense staining was defined as positive, while faint or focal staining and non-staining were considered negative. RESULTS: The median age of patients was 55 years. The median observation period was 1415 days. In multivariate analysis of progression-free survival (PFS), liver metastasis, Ki-67 index, and triple-positive staining of NE markers were risk factors. The 5-year PFS rate of patients with and without triple-positive NE markers was 56.3% and 23.8%, respectively (P < 0.0001). In multivariate analysis of overall survival (OS), R0 resection, Ki-67 index and triple-positive NE markers (hazard ratio 0.4, P = 0.02) were the risk factors. The 5-year OS rate of patients with and without triple-positive NE markers was 88.8% and 66.4%, respectively (P = 0.014). The tumors of patients without triple-positive NE markers were associated with large tumor size, a high mitotic rate and high Ki-67 index. CONCLUSIONS: Triple-positive NE marker staining was a simple and practical indicator of prognoses in patients with well-differentiated Pan-NETs.

Comprehensive molecular and immunological characterization of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a heterogeneous disease with various etiological factors, and ranks as the second leading cause of cancer-related mortality worldwide due to multi-focal recurrence. We herein identified three major subtypes of HCC by performing integrative analysis of two omics data sets, and clarified that this classification was closely correlated with clinicopathological factors, immune profiles and recurrence patterns. METHODS: In the test study, 183 tumor specimens surgically resected from HCC patients were collected for unsupervised clustering analysis of gene expression signatures and comparative analysis of gene mutations. These results were validated by using genome, methylome and transcriptome data of 373 HCC patients provided from the Cancer Genome Atlas Network. In addition, omics data were obtained from pairs of primary and recurrent HCC. FINDINGS: Comprehensive molecular evaluation of HCC by multi-platform analysis defined three major subtypes: (1) mitogenic and stem cell-like tumors with chromosomal instability; (2) CTNNB1-mutated tumors displaying immune suppression; and (3) metabolic disease-associated tumors, which included an immunogenic subgroup characterized by macrophage infiltration and favorable prognosis. Although genomic and epigenomic analysis explicitly distinguished between HCC with intrahepatic metastasis (IM) and multi-centric HCC (MC), the phenotypic similarity between the primary and recurrent tumors was not correlated to the IM/MC origin, but to the classification. INTERPRETATION: Identification of these HCC subtypes provides further insights into patient stratification as well as presents opportunities for therapeutic development. FUND: Ministry of Education, Culture, Sports, Science and Technology of Japan (16H02670 and 18K19575), Japan Agency for Medical Research and Development (JP15cm0106064, JP17cm0106518, JP18cm0106540 and JP18fk0210040).

Tumor suppressor functions of DAXX through histone H3.3/H3K9me3 pathway in pancreatic NETs.

Pancreatic neuroendocrine tumors (PanNETs) have considerable malignant potential. Frequent somatic mutations and loss of DAXX protein expression have been found in PanNETs. DAXX is known as a transcriptional repressor; however, molecular functions underlying DAXX loss remain unclear in PanNETs. We evaluated DAXX expression by immunohistochemistry in 44 PanNETs. DAXX-knockdown (KD) and -knockout (KO) PanNET cells were analyzed for in vitro and vivo The target genes were screened by microarray and chromatin immunoprecipitation (ChIP) assays for DAXX, histone H3.3 and H3K9me3 complex. In clinicopathological features, low DAXX expression was significantly correlated with nonfunctional tumors, higher Ki-67 index and WHO grade. Microarray and ChIP assays of DAXX-KD/KO identified 12 genes as the direct targets of DAXX transcriptional repressor. Among them, expression of five genes including STC2 was suppressed by DAXX/H3.3/H3K9me3 pathway. DAXX-KD/KO cells enhanced sphere forming activity, but its effect was suppressed by knockdown of STC2 In xenograft models, tumorigenicity and tumor vessel density were significantly increased in DAXX-KO cells with high expression of STC2. Clinically, higher recurrence rate was recognized in PanNETs with low expression of DAXX and high expression of STC2 than others (P = 0.018). Our data suggest that DAXX plays as a tumor suppressor and DAXX/H3.3 complex suppresses target genes by promoting H3K9me3 in PanNETs. Combination of DAXX loss and its target gene STC2 overexpression might be effective biomarkers and therapeutic candidates.