Outcome of robot-assisted surgery for stage IA endometrial cancer compared to open and laparoscopic surgeries: a retrospective study at a single institution.

Few studies have compared the efficacy of robot-assisted, laparoscopic, and open surgeries for endometrial cancer. When considering the position of robotic surgery in Japan, it was necessary to determine whether it was effective or not. We aimed to compare the efficacy and safety of these three types of surgeries for early-stage endometrial cancer. In total, 175 patients with endometrial cancer of preoperative stage IA, who had undergone laparotomic (n = 80), laparoscopic (n = 40), or robot-assisted (n = 55) modified radical hysterectomy at our hospital from 2010 to 2022, were included; surgical outcomes, perioperative complications, and prognoses were compared. Total operative and console times for robot-assisted surgery between patients who did or did not undergo pelvic lymphadenectomy were assessed. The robot-assisted group had the shortest total operative time. The estimated blood loss was lower in the laparoscopic and robot-assisted groups than in the laparotomy group. In advanced postoperative stage IA cases, there were no differences in progression-free and overall survival among the three groups. In the robot-assisted group, the operative time decreased as the number of operations increased; the learning curve was reached after 10 cases each of patients with and without pelvic lymphadenectomy. The frequency of perioperative complications of Clavien-Dindo classification Grade 1 or higher was the lowest in the robot-assisted group (p = 0.02). There were no complications of Clavien-Dindo classification Grade 2 or higher in the robot-assisted group. Robot-assisted surgery for stage IA endometrial cancer, a minimally invasive procedure, has fewer operative times and complications than those of laparoscopic and open surgeries in a single institution in Japan.

Malignant Pericardial Tamponade Secondary to Ovarian Clear Cell Carcinoma.

Malignant pericardial effusion is an uncommon metastatic manifestation of ovarian carcinoma. Few cases of ovarian serous carcinoma have been previously reported. Ovarian clear cell carcinoma is the second most common histologic subtype in East Asian countries and is a relatively rare in Western countries. Here, we report the case of cardiac tamponade secondary to Ovarian clear cell carcinoma. A 46-year-old woman with recurrent Ovarian clear cell carcinoma presented with worsening cough, palpitations, and shortness of breath during chemotherapy. Chest radiography and computed tomography confirmed a pleural effusion with cardiac tamponade. The patient underwent pericardial fenestration and drainage for cardiac tamponade. Pericardial fluid cytology showed malignant cells forming papillary and ball-like clusters with irregular stacking. The cells had a mirror ball-like appearance and collagenous stroma, in which a homogenous hyaline core was observed in the center of most tumor cell clusters. Based on these findings, a diagnosis of Ovarian clear cell carcinoma metastasis was made. She received palliative care and died 5 months after the operation without recurrent cardiac tamponade. This case suggests that cytological findings from pericardial effusion are useful in diagnosing Ovarian clear cell carcinoma metastasis.

A genome-wide association study identifies 2 susceptibility Loci for Crohn's disease in a Japanese population.

BACKGROUND & AIMS: Crohn's disease is an inflammatory bowel disease induced by multiple genetic and environmental factors. Genome-wide association studies have identified genetic factors that affect the risk for Crohn's disease in European populations, but information from other ethnic groups is scarce. We therefore investigated genetic factors associated with Crohn's disease in the Japanese population. METHODS: We performed a genome-wide association study with 372 individuals with Crohn's disease (cases) and 3389 controls, all from the Japanese population. To confirm identified associations, we performed a replication study with an independent panel of 1151 Crohn's disease cases and 15,800 controls. We also performed an association analysis using genome-wide genotype imputation in the discovery cohort. RESULTS: We confirmed associations of Crohn's disease with variants in MHC (rs7765379, P = 2.11 × 10(-59)), TNFSF15 (rs6478106, P = 3.87 × 10(-45)), and STAT3 (rs9891119, P = 2.24 × 10(-14)). We identified 2 new susceptibility loci: on chromosome 4p14 (rs1487630, P = 2.40 × 10(-11); odds ratio, 1.33), and in the SLC25A15-ELF1-WBP4 region on 13q14 (rs7329174 in ELF1, P = 5.12 × 10(-9); odds ratio, 1.27). CONCLUSIONS: In a genome-wide association study, we identified 2 new susceptibility loci for Crohn's disease in a Japanese population. These findings could increase our understanding of the pathogenesis of Crohn's disease.

Dynamics of claudins expression in colitis and colitis-associated cancer in rat.

Claudins comprise a multigene family of 24 species and have been shown to constitute the backbone of tight junction strands in simple epithelial cells and to be directly involved in their barrier functions. Apical-most tight junction protein complexes (TJs) are implicated in inflammatory bowel disease (IBD) pathophysiology. Except for claudin-8, TJs explored in this study (including ZO-1, claudin-1, -2, -3, -7, -12, and -15) were found to be expressed in rat colonic tissues. ZO-1 and claudin-7 were ubiquitously expressed in all study groups. As depicted in Fig. 1b, expressions of claudin-2, -12, and -15 significantly diminished after combined treatment with dextran sulfate sodium (DSS) and busulfan (BU) (lane 5), compared with either agent alone (lanes 2 and 4). Despite the lack of significance, there appeared to be a subtle dose-dependent decrease with DSS treatment (lanes 2 and 3). In contrast to these results obtained from DSS colitis, expression of claudin-1 was significantly downregulated, while expression of claudin-15 was upregulated in colitis-associated cancer tissues in the azoxymethane (AOM)/DSS model (Fig. 2b). It is very intriguing that claudins' expression dynamics were mutually exclusive between colitis and colitis-associated cancer in rats. However, the biological significance of disease-specific claudin expression profiles will remain elusive until the specific expression and function of each claudin in a tissue- and cell-type relationship are comprehensively clarified. Currently, the physiologic consequences of the diversity of TJ barrier function resulting from multiple combinations of claudins are only beginning to be recognized. Full unraveling of these complexities could inspire a new paradigm of inflammation and cancer, and eventually translate to clinical practice on IBD.

[A case of hepatocellular carcinoma diagnosed based on the result of a bone biopsy, in which the primary hepatocellular carcinoma was identified in the liver 14 months after the initial diagnosis].

A 64-year-old man complained of pain in his left humerus. A histopathological examination of biopsy specimens taken from the lesion revealed a hepatocellular carcinoma. No primary hepatic lesion was revealed in a subsequent examination performed at this time. Enhanced computed tomography examination of the abdomen 14 months later, showed a nodular lesion, approximately 15 mm in diameter, therefore a partial hepatectomy was performed. The lesion was histopathologically diagnosed as a moderately-poorly differentiated hepatocellular carcinoma. The inability to identify the primary hepatocellular carcinoma is quite rare, and the present case may be the first report of the discovery of the primary hepatocellular cancer after the diagnosis of a secondary lesion.

Myogenic lineage differentiated mesenchymal stem cells enhance recovery from dextran sulfate sodium-induced colitis in the rat.

BACKGROUND: Although mounting evidence implicates mesenchymal stem cells (MSCs) in intestinal tissue repair, uncertainty remains concerning the distribution, function, and fate of repopulating MSCs in recipient colonic tissues. Therefore, we investigated the role of transplanted MSCs in the repair phase of DSS colitis. METHODS: LacZ-labeled rat MSCs were transplanted into rats with colitis induced by 4% DSS on day 2. Regular water replaced the DSS solution on day 6. Therapeutic effect was evaluated on day 9 by clinicopathologic and growth factor/cytokine expression profiles. We analyzed the Notch signaling pathway by Western blotting and characterized immunofluorescence of lacZ-labeled MSCs with confocal laser microscopy. In vivo differentiation of MSC was confirmed by transmission electron microscopy (TEM). RESULTS: Recovery of colitis was modestly but significantly promoted by MSC transplantation due to proceeding cell cycle and inhibiting apoptosis in the epithelia. Tgfa mRNA expression increased significantly, while Notch signaling was inhibited in the colonic tissues with MSC transplantation. ß-Galactosidase-positive cells, which expressed α-SMA, desmin, and vimentin, were infrequently detected in the lamina propria stroma. DSS exposure in vitro proved to be the most potent inducer for α-SMA in MSCs where TEM demonstrated myogenic lineage differentiation. CONCLUSIONS: We found that MSCs transplantation modestly promoted the repair of DSS colitis. The donor-derived MSCs were likely reprogrammed to differentiate to myogenic lineage cells by cues from the micro milieu. Further characterization of these cells is warranted as a basis for applying cell-based therapy for inflammatory bowel disease.

Involvement of the tubulin tyrosine ligase-like family member 4 polyglutamylase in PELP1 polyglutamylation and chromatin remodeling in pancreatic cancer cells.

Polyglutamylation is a new class of posttranslational modification in which glutamate side chains are formed in proteins, although its biological significance is not well known. Through our genome-wide gene expression profile analyses of pancreatic ductal adenocarcinoma (PDAC) cells, we identified the overexpression of tubulin tyrosine ligase-like family member 4 (TTLL4) in PDAC cells. Subsequent reverse transcription-PCR and Northern blot analyses confirmed its upregulation in several PDACs. TTLL4 belongs to the TTLL family which was reported to have polyglutamylase activity. Knockdown of TTLL4 by short hairpin RNA in PDAC cells attenuated the growth of PDAC cells and exogenous introduction of TTLL4 enhanced cell growth. We also found that TTLL4 expression was correlated with polyglutamylation levels of a glutamate stretch region of the proline, glutamate, and leucine-rich protein 1 (PELP1) that was shown to interact with various proteins such as histone H3, and was involved in several signaling pathways through its function as a scaffold protein. PELP1 polyglutamylation could influence its interaction with histone H3 and affect histone H3 acetylation. We also identified the interaction of PELP1 with LAS1L and SENP3, components of the MLL1-WDR5 supercomplex involving chromatin remodeling. Our findings imply that TTLL4 could play important roles in pancreatic carcinogenesis through its polyglutamylase activity and subsequent coordination of chromatin remodeling, and might be a good molecular candidate for the development of new therapeutic strategies for pancreatic cancer.

A genome-wide association study identifies three new susceptibility loci for ulcerative colitis in the Japanese population.

Ulcerative colitis is one of the principal forms of inflammatory bowel disease with complex manifestations. Although previous studies have indicated that there is a genetic contribution to the pathogenesis of ulcerative colitis, the genes influencing susceptibility to the disease have not been fully determined. To identify genetic factors conferring risk of ulcerative colitis, here we conducted a two-stage genome-wide association study and subsequent replication study using 1,384 Japanese individuals with ulcerative colitis and 3,057 control subjects. In addition to the expected strong association with the major histocompatibility complex (MHC) region, we identified three new susceptibility loci: the immunoglobulin receptor gene FCGR2A (rs1801274, P = 1.56 x 10(-12)), a locus on chromosome 13q12 (rs17085007, P = 6.64 x 10(-8)) and the glycoprotein gene SLC26A3 (rs2108225, P = 9.50 x 10(-8)). rs1801274 is a nonsynonymous SNP of FCGR2A that is reported to have a critical effect on receptor binding affinity for IgG and to be associated with other autoimmune diseases. Our findings provide insight into the molecular pathogenesis of ulcerative colitis.

Genetic variants in surfactant, pulmonary-associated protein D (SFTPD) and Japanese susceptibility to ulcerative colitis.

BACKGROUND: Identifying culprit genes for a complex trait in a homogeneous population such as the Japanese remains challenging. We aimed to use previous achievements of genome-wide association studies to identify precise susceptibility loci for inflammatory bowel disease in Japanese people and to simultaneously investigate the replication of recently identified susceptibility loci. METHODS: An unrelated Japanese population of 174 Crohn's disease patients, 296 ulcerative colitis (UC) patients, and 394 healthy controls was consecutively enrolled in this study. Genotype and haplotype analyses focusing on susceptibility to inflammatory bowel disease were performed using 7 single nucleotide polymorphisms (SNPs) including 5 HapMap tag SNPs within surfactant, pulmonary-associated protein D (SFTPD) along with the 2 Caucasian susceptibility loci. We performed fine-scale mapping of trait-associated loci with the extension of a shattered coalescent process in a Bayesian framework. Epistasis on disease phenotypes was statistically explored with the interaction dendrogram. RESULTS: A minor allele G of rs911887 reached statistical significance for susceptibility to UC. The 2-allele haplotype GG comprising rs911887 and rs2243639 (Ala160Thr) within SFTPD was significantly associated with susceptibility to UC. A posterior density plot shows that trait-associated variants in the vicinity of rs911887 are likely to exist. An association between NKX2-3 and UC susceptibility was replicated and diverse evidence of epistasis in Japan was suggested. CONCLUSIONS: This preliminary study suggests that SFTPD is both a susceptibility gene and a disease-modifying gene for UC in Japanese. Replication of the causality and functional analyses of SFTPD is urgently warranted.

Enhancing epithelial engraftment of rat mesenchymal stem cells restores epithelial barrier integrity.

The cellular origin, in vivo function and fate of donor bone marrow-derived cells residing in the recipient intestinal epithelial cells, pericryptal myofibroblasts or endothelial cells remain obscure. Although 'immunoprivileged' mesenchymal stem cells (MSCs) are prime candidates for cell- and gene-based therapy, their precise role in colitis remains largely undetermined. Using a dextran sulphate sodium (DSS) colitis with busulphan (BU)-induced hypoplastic marrow model, we examined the therapeutic effects of MSC transplantation, focusing on the role of MSCs as both cell providers and immunomodulators. Donor-derived MSCs were detected by eGFP immunofluorescence and fluorescence in situ hybridization for Y-chromosome (Y-FISH) analysis. Western blot analysis of apical-most tight junction proteins was performed with antibodies against claudin-2, -7, -8, -12, -13, -15 and ZO-1. Cytokine and cell cycle profiles were analysed by semi-quantitative RT-PCR and flow cytometry. Susceptibility to DSS colitis was significantly increased by co-existing BU-induced bone marrow hypoplasia and this increase was significantly reduced by enhancing epithelial engraftment of MSCs, an effect depending on restoring epithelial barrier integrity rather than inhibiting host immune responses. We provide evidence that implicates MSCs in maintaining epithelial barrier function by reassembling apical-most tight junction proteins, claudins. The therapeutic efficacy of extrinsic MSCs depends on enhancing epithelial engraftment in damaged crypts by busulphan conditioning. Such a role for the MSC-derived intestinal cells in colitis therapy merits further examination and may offer a promising new treatment for inflammatory bowel disease (IBD).

Identification of C2orf18, termed ANT2BP (ANT2-binding protein), as one of the key molecules involved in pancreatic carcinogenesis.

Pancreatic ductal adenocarcinoma (PDAC) shows one of the worst mortality rates among the common malignancies, and the great majority of PDAC patients are diagnosed at an advanced stage where no effective therapy is presently available. Hence, identification of novel molecular targets and development of molecular therapy for PDAC are urgently required. Through our genome-wide gene expression profiles of microdissected PDAC cells, we here identified a novel gene C2orf18 as a molecular target for PDAC treatment. Transcriptional and immunohistochemical analysis validated its overexpression in PDAC cells and limited expression in normal adult organs. Knockdown of C2orf18 by small-interfering RNA in PDAC cell lines resulted in induction of apoptosis and suppression of cancer cell growth, suggesting its essential role in maintaining viability of PDAC cells. We showed that C2orf18 was localized in the mitochondria and it could interact with adenine nucleotide translocase 2 (ANT2), which is involved in maintenance of the mitochondrial membrane potential and energy homeostasis, and was indicated some roles in apoptosis. These findings implicated that C2orf18, termed ANT2-binding protein (ANT2BP), might serve as a candidate molecular target for pancreatic cancer therapy.

Over-expression of cysteine proteinase inhibitor cystatin 6 promotes pancreatic cancer growth.

Pancreatic ductal adenocarcinoma (PDAC) shows the worst mortality among the common malignancies and development of novel therapies for PDAC through identification of good molecular targets is an urgent issue. Among dozens of over-expressing genes identified through our gene-expression profile analysis of PDAC cells, we here report CST6 (Cystatin 6 or E/M) as a candidate of molecular targets for PDAC treatment. Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical analysis confirmed over-expression of CST6 in PDAC cells, but no or limited expression of CST6 was observed in normal pancreas and other vital organs. Knock-down of endogenous CST6 expression by small interfering RNA attenuated PDAC cell growth, suggesting its essential role in maintaining viability of PDAC cells. Concordantly, constitutive expression of CST6 in CST6-null cells promoted their growth in vitro and in vivo. Furthermore, the addition of mature recombinant CST6 in culture medium also promoted cell proliferation in a dose-dependent manner, whereas recombinant CST6 lacking its proteinase-inhibitor domain and its non-glycosylated form did not. Over-expression of CST6 inhibited the intracellular activity of cathepsin B, which is one of the putative substrates of CST6 proteinase inhibitor and can intracellularly function as a pro-apoptotic factor. These findings imply that CST6 is likely to involve in the proliferation and survival of pancreatic cancer probably through its proteinase inhibitory activity, and it is a promising molecular target for development of new therapeutic strategies for PDAC.

Gamma-aminobutyric acid (GABA) stimulates pancreatic cancer growth through overexpressing GABAA receptor pi subunit.

Gamma-aminobutyric acid (GABA) functions primarily as an inhibitory neurotransmitter in the mature central nervous system, and GABA/GABA receptors are also present in nonneural tissues, including cancer, but their precise function in nonneuronal or cancerous cells has thus far been poorly defined. Through the genome-wide cDNA microarray analysis of pancreatic ductal adenocarcinoma (PDAC) cells as well as subsequent reverse transcription-PCR and Northern blot analyses, we identified the overexpression of GABA receptor pi subunit (GABRP) in PDAC cells. We also found the expression of this peripheral type GABAA receptor subunit in few adult human organs. Knockdown of endogenous GABRP expression in PDAC cells by small interfering RNA attenuated PDAC cell growth, suggesting its essential role in PDAC cell viability. Notably, the addition of GABA into the cell culture medium promoted the proliferation of GABRP-expressing PDAC cells, but not GABRP-negative cells, and GABAA receptor antagonists inhibited this growth-promoting effect by GABA. The HEK293 cells constitutively expressing exogenous GABRP revealed the growth-promoting effect of GABA treatment. Furthermore, GABA treatment in GABRP-positive cells increased intracellular Ca2+ levels and activated the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/Erk) cascade. Clinical PDAC tissues contained a higher level of GABA than normal pancreas tissues due to the up-regulation of glutamate decarboxylase 1 expression, suggesting their autocrine/paracrine growth-promoting effect in PDACs. These findings imply that GABA and GABRP could play important roles in PDAC development and progression, and that this pathway can be a promising molecular target for the development of new therapeutic strategies for PDAC.

Oncogenic role of KIAA0101 interacting with proliferating cell nuclear antigen in pancreatic cancer.

To isolate novel diagnostic markers and therapeutic targets for pancreatic cancer, we earlier did expression profile analysis of pancreatic cancer cells using a genome-wide cDNA microarray combined with microdissection. Among dozens of trans-activated genes in pancreatic cancer cells, this study focused on KIAA0101 whose overexpression in pancreatic cancer cells was validated by immunohistochemical analysis. KIAA0101 was previously identified as p15(PAF) [proliferating cell nuclear antigen (PCNA)-associated factor] to bind with PCNA; however, its function remains unknown. To investigate for the biological significance of KIAA0101 overexpression in cancer cells, we knocked down KIAA0101 by small interfering RNA (siRNA) in pancreatic cancer cells and found that the reduced expression by siRNA caused drastic attenuation of their proliferation as well as significant decrease in DNA replication rate. Concordantly, exogenous overexpression of KIAA0101 enhanced cancer cell growth, and NIH3T3 derivative cells expressing KIAA0101 revealed in vivo tumor formation, implying its growth-promoting and oncogenic property. We also showed that the expression of KIAA0101 was regulated tightly by the p53-p21 pathway. To consider the KIAA0101/PCNA interaction as a therapeutic target, we designed the cell-permeable 20-amino-acid dominant-negative peptide and found that it could effectively inhibit the KIAA0101/PCNA interaction and resulted in the significant growth suppression of cancer cells. Our results clearly implicated that suppression of the KIAA0101 and PCNA oncogenic activity, or the inhibition of KIAA0101/PCNA interaction, is likely to be a promising strategy to develop novel cancer therapeutic drugs.

EphA4 receptor, overexpressed in pancreatic ductal adenocarcinoma, promotes cancer cell growth.

To isolate novel diagnostic markers and drug targets for pancreatic ductal adenocarcinoma (PDAC), we previously performed expression profile analysis of PDAC cells using a genome-wide cDNA microarray combined with laser microdissection. Among dozens of up-regulated genes identified in PDAC cells, we herein focused on one tyrosine kinase receptor, Eph receptor A4 (EphA4), as a molecular target for PDAC therapy. Immunohistochemical analysis validated EphA4 overexpression in approximately half of the PDAC tissues. To investigate its biological function in PDAC cells, we knocked down EphA4 expression by siRNA, which drastically attenuated PDAC cell viability. In concordance with the siRNA experiment, PDAC-derivative cells that were designed to constitutively express exogenous EphA4 showed a more rapid growth rate than cells transfected with mock vector, suggesting a growth-promoting effect of EphA4 on PDAC cells. Furthermore, the expression analysis for ephrin ligand family members indicated the coexistence of ephrinA3 ligand in PDAC cells with EphA4 receptor, and knockdown of ephrinA3 by siRNA also attenuated PDAC cell viability. These results suggest that the EphA4-ephrinA3 pathway is likely to be a promising molecular target for pancreatic cancer therapy.

Novel tumor marker REG4 detected in serum of patients with resectable pancreatic cancer and feasibility for antibody therapy targeting REG4.

Pancreatic ductal adenocarcinoma (PDAC) shows the worst mortality rate among common malignancies, with a 5-year survival rate of only 4%, and the majority of PDAC patients are diagnosed at an advanced stage in which no effective therapy is available at present. Although the proportion of curable cases is still not so high, surgical resection of early stage PDAC is the only way to cure the disease. Hence, establishment of a screening strategy to detect early stage PDAC by novel serological markers is required urgently, and development of novel molecular therapies for PDAC treatment is also eagerly expected. We here report overexpression of REG4, a new member of the regenerating islet-derived (REG) family, in PDAC cells on the basis of genome-wide cDNA microarray analysis as well as reverse transcription-polymerase chain reaction and immunohistochemical analysis. We also detected significant elevation of REG4 in the serum of some patients with early-stage PDAC using our enzyme-linked immunosorbent assay system, indicating the possibility of REG4 as a new serological marker of PDAC. Furthermore, we found that knockdown of endogenous REG4 expression in PDAC cell lines with small interfering RNA caused a decrease in cell viability. Concordantly, addition of recombinant REG4 to the culture medium enhanced growth of a PDAC cell line in a dose-dependent manner. A monoclonal antibody against REG4 neutralized its growth-promoting effects and attenuated significantly the growth of PDAC cells. These findings indicate that REG4 is a promising tumor marker to screen early-stage PDAC, and also that neutralization of REG4 by the antibody may offer novel potential tools for the treatment of PDAC.

Overexpressed P-cadherin/CDH3 promotes motility of pancreatic cancer cells by interacting with p120ctn and activating rho-family GTPases.

P-Cadherin/CDH3 belongs to the family of classic cadherins that are engaged in various cellular activities including motility, invasion, and signaling of tumor cells, in addition to cell adhesion. However, the biological roles of P-cadherin itself are not fully characterized. Based on information derived from a previous genome-wide cDNA microarray analysis of microdissected pancreatic ductal adenocarcinoma (PDAC), we focused on P-cadherin as one of the genes most strongly overexpressed in the great majority of PDACs. To investigate the consequences of overexpression of P-cadherin in terms of pancreatic carcinogenesis and tumor progression, we used a P-cadherin-deficient PDAC cell line, Panc-1, to construct a cell line (Panc1-CDH3) that stably overexpressed P-cadherin. Induction of P-cadherin in Panc1-CDH3 increased the motility of the cancer cells, but a blocking antibody against P-cadherin suppressed the motility in vitro. Overexpression of P-cadherin was strongly associated with cytoplasmic accumulation of one of the catenins, p120ctn, and cadherin switching in PDAC cells. Moreover, P-cadherin-dependent activation of cell motility was associated with activation of Rho GTPases, Rac1 and Cdc42, through accumulation of p120ctn in cytoplasm and cadherin switching. These findings suggest that overexpression of P-cadherin is likely to be related to the biological aggressiveness of PDACs; blocking of P-cadherin activity or its associated signaling could be a novel therapeutic approach for treatment of aggressive pancreatic cancers.

Carcinoma of duodenum arising from Brunner's gland.

Primary carcinoma of the duodenum is a rare lesion. In conjunction with the widespread use of panendoscopy, reported cases of carcinoma of the duodenum have recently increased. Although benign hyperplasia of Brunner's gland is well documented, duodenal carcinoma originating in Brunner's gland is extremely rare, and, consequently, there is little data on the morphological or histochemical characteristics. We report here a case of early duodenal carcinoma arising from Brunner's gland, whose origin was proven by mucin immunohistochemistry.