Toru Kawamoto

BENEFITS OF ADJUVANT RADIOTHERAPY AFTER RADICAL RESECTION OF LOCALLY ADVANCED MAIN HEPATIC DUCT CARCINOMA

PURPOSE The objective of this study was to determine the benefits of adjuvant radiotherapy after radical resection of locally advanced main hepatic duct carcinoma (Klatskin tumor). METHODS AND MATERIALS We conducted a retrospective review of 63 patients who underwent surgical resection of Stage IVA Klatskin tumor. Of the 63 patients, 47 had microscopic tumor residue (RT1). Twenty-eight of the 47 patients with RT1 were treated by adjuvant radiotherapy and the remaining 19 patients were treated exclusively by surgical resection. Seventeen of the 28 patients with RT1 were treated by both intraoperative radiotherapy (IORT) and postoperative radiotherapy (PORT); of the remaining 11 patients with RT1, 6 underwent resection and IORT, and 5 underwent resection and PORT. RESULTS The major complication and 30-day operative death rates were significantly lower in the radiation group (9.5% and 0.0%, respectively) than in the resection alone group (28.5% and 9.5%, respectively). Of the eight 5-year survivors with RT1, 6 had adjuvant radiotherapy and the remaining 2 had resection alone. Adjuvant radiotherapy for patients with RT1 yielded significantly (p = 0.0141) higher 5-year survival rates (33.9%) than in the resection alone group (13.5 %). The best 5-year survival rate (39.2 %) was found in patients who underwent a combination of IORT and PORT after resection. The local-regional control rate was significantly higher in the adjuvant radiation group than in the resection alone group (79.2% vs. 31.2%). CONCLUSION Our data clearly suggest the improved prognosis of patients with locally advanced Klatskin tumor by integrated adjuvant radiotherapy with IORT and PORT to complete gross tumor resection with acceptable treatment mortality and morbidity.

Hepatoid adenocarcinoma of the stomach

Although gastric cancer occurs frequently in Japan, few cases of hepatoid adenocarcinoma, a cancer with an extremely poor prognosis, have been reported. Here, we describe a 67-year-old Japanese man referred to our hospital with suspected gastric cancer. Gastrointestinal fiberscopy revealed an elevated lesion with a central depression on the lesser curvature, extending from the antrum to the body of the stomach. On the preoperative examinations, abdominal computed tomography scan, magnetic resonance imaging, and abdominal ultrasonography revealed multiple metastases to the liver and no cirrhotic change. The serum level of alpha-fetoprotein (AFP) was markedly elevated (10,084 ng/ml). After a diagnosis of AFP-producing gastric cancer with multiple liver metastases was made, total gastrectomy, without liver resection, was performed. Microscopically, the tumor showed two main histological features. The main part of the tumor resembled moderately differentiated hepatocellular carcinoma, and the rest showed fetal-type adenocarcinoma. Some parts of the hepatoma-like lesion showed periodic acid-Schiff (PAS)-positive granules. Furthermore, the tumor showed diffuse immunohistochemical positivity for AFP, alpha-1 antitrypsin, and alpha-1 antichymotrypsin. According to these histopathological findings, the tumor was diagnosed as hepatoid adenocarcinoma of the stomach. Although anastomotic leakage occurred postoperatively and the liver metastases have increased in size, the patient remains alive 11 months after the operation. Because of the poor prognosis for this histological type of tumor, accurate diagnosis of hepatoid adenocarcinoma is important, and long-term follow-up is required. We describe this rare case of hepatoid adenocarcinoma of the stomach, and review the literature concerning the clinicopathological aspects.

Hedgehog Promotes Neovascularization in Pancreatic Cancers by Regulating Ang-1 and IGF-1 Expression in Bone-Marrow Derived Pro-Angiogenic Cells

Background The hedgehog (Hh) pathway has been implicated in the pathogenesis of cancer including pancreatic ductal adenocarcinoma (PDAC). Recent studies have suggested that the oncogenic function of Hh in PDAC involves signaling in the stromal cells rather than cell autonomous effects on the tumor cells. However, the origin and nature of the stromal cell type(s) that are responsive to Hh signaling remained unknown. Since Hh signaling plays a crucial role during embryonic and postnatal vasculogenesis, we speculated that Hh ligand may act on tumor vasculature specifically focusing on bone marrow (BM)-derived cells. Methodology/Principal Findings Cyclopamine was utilized to inhibit the Hh pathway in human PDAC cell lines and their xenografts. BM transplants, co-culture systems of tumor cells and BM-derived pro-angiogenic cells (BMPCs) were employed to assess the role of tumor-derived Hh in regulating the BM compartment and the contribution of BM-derived cells to angiogenesis in PDAC. Cyclopamine administration attenuated Hh signaling in the stroma rather than in the cancer cells as reflected by decreased expression of full length Gli2 protein and Gli1 mRNA specifically in the compartment. Cyclopamine inhibited the growth of PDAC xenografts in association with regression of the tumor vasculature and reduced homing of BM-derived cells to the tumor. Host-derived Ang-1 and IGF-1 mRNA levels were downregulated by cyclopamine in the tumor xenografts. In vitro co-culture and matrigel plug assays demonstrated that PDAC cell-derived Shh induced Ang-1 and IGF-1 production in BMPCs, resulting in their enhanced migration and capillary morphogenesis activity. Conclusions/Significance We identified the BMPCs as alternative stromal targets of Hh-ligand in PDAC suggesting that the tumor vasculature is an attractive therapeutic target of Hh blockade. Our data is consistent with the emerging concept that BM-derived cells make important contributions to epithelial tumorigenesis.

Wisteria floribunda Agglutinin-Positive Mucin 1 Is a Sensitive Biliary Marker for Human Cholangiocarcinoma

Cholangiocarcinoma (CC) is an aggressive malignant tumor for which useful markers are not presently available for early and precise diagnosis. The aim of this study was therefore to identify a high‐performance diagnostic marker with a special focus on glyco‐alteration of glycoproteins. In the course of study, we found that Wisteria floribunda agglutinin (WFA) is the best probe to differentiate intrahepatic cholangiocarcinoma (ICC) lesions from normal bile duct epithelia (BDE) (P < 0.0001). The subsequent histochemical study confirmed ICC‐specific WFA staining on 165 tissue specimens. On the other hand, the WFA staining was shown to be closely associated with that of MY.1E12 established previously against sialylated mucin 1 (MUC1) by double‐staining experiments. Moreover, glyco‐alteration of MUC1 could be verified by western blotting of WFA‐captured bile samples from patients with CC patients. Thus, we attempted to construct an enzyme‐linked immunosorbent assay system for more convenient CC diagnosis, where WFA‐coated plates, the specific monoclonal antibody MY.1E12, and the bile specimens from CC including ICC (n = 30) and benign diseases (n = 38) were combined. As a result, CC was clearly distinguished from benign diseases with statistical scores (sensitivity = 90.0%, specificity = 76.3%, and area under the curve = 0.85). As a particular note, the obtained sensitivity is the highest score among those having been so far reported. Conclusion: Our approach focusing significant glyco‐alteration of a particular glycoprotein yielded a novel diagnostic system for CC with satisfactory clinical scores. HEPATOLOGY 2010

Enteral Vitamin B12 Supplements Reverse Postgastrectomy B12 Deficiency

ObjectiveTo examine the development of chemical and clinical vitamin B12 deficiency after total gastrectomy, and to evaluate the efficacy of supplemental oral B12 administration. Summary Background DataPostgastrectomy anemia is due to deficiencies of iron and vitamin B12, and parenteral B12 administration is the only appropriate treatment. However, no guidelines exist for the prophylactic use of B12 in patients who undergo total gastrectomy, the clinical presentation of B12 deficiency in this context has not been defined, and the question of whether oral B12 administration can be used to prevent and treat B12 deficiency has not been examined. MethodsSerum B12 concentrations were measured in 31 patients who had undergone total gastrectomy. Symptoms related to B12 deficiency were surveyed in detail. Serum B12 concentrations were measured every 6 months after total gastrectomy in 10 patients. Thirty one patients received supplemental B12: 18 patients orally and 13 by intramuscular injection. ResultsThe B12 concentration dropped below the lower limit of normal (200 pg/mL) for the first time in two patients at 1 year, in four patients at 2 years, in three patients at 3 years, and in one patient at 4 years. Seventy-eight percent of patients reported some symptoms related to B12 deficiency. The serum B12 concentration in patients who received supplemental B12 orally increased rapidly and all symptoms resolved with oral therapy alone. ConclusionsB12 deficiency can develop as early as 1 year after total gastrectomy and causes symptoms. Because enteral B12 treatment increases the serum B12 concentration and leads to rapid resolution of symptoms, it should be prescribed routinely to patients undergoing total gastrectomy.

Development of an all-in-one technology for glycan profiling targeting formalin-embedded tissue sections

An ultra-sensitive method for glycan analysis targeting small tissue sections (1.5mm in diameter) is described as an application of a recently-established lectin microarray technology. The developed system achieved a high level of detection of a tissue section consisting of approximately 500 cells for differential profiling, where both N- and O-glycans attached to a pool of glycoproteins are subjected to multiplex analysis with 43 lectins. By using an optimized protocol for differential glycan analysis, sections of adenocarcinoma (n=28) and normal epithelia (n=12) of the colon were analyzed in an all-in-one manner. As a result, Wisteria floribunda agglutinin (WFA) was found to clearly differentiate cancerous from normal epithelia with P<0.0001. The obtained results correlated well with the subsequent histochemical study using biotinylated WFA. Thus, the developed technology proved to be valid for expanding the lectin microarray applications to tissue-based glycomics, and hence, should accelerate a discovery phase of glycan-related biomarkers.

Therapeutic Effect of Rapamycin on Gallbladder Cancer in a Transgenic Mouse Model

The macrolide fungicide rapamycin has shown significant antiproliferative action toward a variety of tumor types. In this study, we used BK5.erbB2 transgenic mice as an animal model to examine the therapeutic effect of rapamycin as a potential treatment for gallbladder cancer. Homozygous BK5.erbB2 mice overexpressing the wild-type rat erbB2 gene in basal epithelial cells of the gallbladder have an approximately 70% incidence of gallbladder adenocarcinoma by 2 to 3 months of age. Groups of mice ( approximately 2-3 months of age) were treated with rapamycin by i.p. injection (once daily for 14 days) and then sacrificed 24 h after the last treatment. Rapamycin significantly reduced the incidence and severity of gallbladder carcinoma in BK5.erbB2 mice in a dose-dependent manner. Tumors responsive to treatment exhibited a higher number of apoptotic cells. Furthermore, rapamycin treatment led to decreased levels of phosphorylated p70 S6 kinase (Thr(389)) in gallbladder tissue as assessed by both Western blot and immunofluorescence analyses. Finally, immunofluorescence staining revealed elevated phosphorylated Akt (Ser(473)) and phosphorylated mammalian target of rapamycin (mTOR; Ser(2448)) in human gallbladder cancer compared with normal gallbladder tissue. Based on our results using a novel genetically engineered mouse model and the fact that the Akt/mTOR pathway is activated in human gallbladder cancer, rapamycin and related drugs may be effective therapeutic agents for the treatment of human gallbladder cancer.

Solitary schwannoma of the colon: report of two cases.

Abstract Some patients with gastrointestinal schwannoma (GIS) have been previously reported in the literature. However, GIS of the colon is quite rare. In addition, it is sometimes difficult to differentiate neurogenic tumors from other soft tissue tumors. We herein describe two cases of schwannoma of the colon, while also reviewing the relevant Japanese literature. The first case, a 73-year-old woman underwent a sigmoidectomy with lymph node dissection following the diagnosis of submucosal tumor. In the second case, a submucosal tumor was located in the cecum of a 44-year-old man. An endoscopic tumor resection was performed in the second case. The resected tumors measured 3.6 and 1.0 cm in maximal diameter, respectively. Microscopically, the tumors consisted predominantly of spindle-shaped cells that proliferated in an interlaced fashion. Mitosis was rarely seen in these tumors. Immunohistochemically, the tumor cells were strongly positive for S-100 protein, weakly positive for glial fibrillary acidic protein, and negative for CD34, α-smooth-muscle actin, and cytokeratin (CAM 5.2) in both cases. The tumors in the two cases were both diagnosed to be benign schwannoma of the colon. In general, schwannoma of the gastrointestinal tract is considered to be benign and should therefore be distinguished from other spindle-cell tumors or malignancies. Once diagnosed as schwannoma, extensive surgery should be avoided. Actually, such patients tend to show a good postoperative course with no evidence of recurrence.

Expression of cyclooxygenase-2 in the subserosal layer correlates with postsurgical prognosis of pathological tumor stage 2 carcinoma of the gallbladder.

Postsurgical recurrence at distant sites frequently occurs in pathological tumor stage 2 (pT2) carcinoma of the gallbladder even though the carcinoma is limited to the gallbladder wall. Little is known, however, about the molecular events leading to its development and progression. A large body of evidence suggests that cyclooxygenase‐2 (COX‐2) is up‐regulated in carcinoma tissues and plays roles in promoting cell‐proliferation, growth and metastasis of carcinoma cells. In the present study, immunohistochemistry was performed to determine the expression levels of COX‐2 in the subserosal layer of 33 cases of pT2 gallbladder carcinoma in which curative resections had been performed and to determine the correlations of the expression levels of COX‐2 with mode of recurrence and postsurgical survival. Immunostaining of COX‐2 in the epithelia was recognized in more than 80% of normal epithelia, noncancerous pathological lesions of the gallbladder except for intestinal metaplasia and pT1–4 carcinoma specimens. Intense staining was observed in large percentages of hyperplastic lesions (65%), pT2 carcinoma specimens (76%) and pT3 and pT4 carcinoma specimens (64%) compared to the percentages of normal epithelia and other pathological lesions (0–25%). Intense staining was also observed in the adjacent stroma in pT2 carcinoma specimens (33%) and in those in pT3 and pT4 carcinoma specimens (43%) but only in small percentages of the stroma adjacent to normal epithelia and pathological lesions (0–8%). In situ hybridization confirmed the existence of COX‐2 mRNA in both the cancerous epithelia and adjacent stroma of pT2‐pT4 carcinomas. In 33 cases of pT2 carcinoma, distant recurrence, i.e., liver metastasis, was seen in 3 of 9 cases of pT2 carcinoma (33%, P<0.05) with intense stromal staining in the subserosal layer and in 1 of 24 cases (4%) without intense staining, whereas no significant correlation was found between parameters of pathological malignancies (histological grade, lymphatic permeation, venous permeation and lymph node metastasis) and the intensity of stromal staining in the subserosal layer. The postsurgical survival outcome was significantly poorer in the former than in the latter (p = 0.010). In pT2 gallbladder carcinoma, upregulation of COX‐2 in the stroma adjacent to the cancerous epithelia in the subserosal layer correlates with the aggressiveness of the disease, such as the tendency to form distant recurrences. This phenotype may serve as a unique biological feature associated with the malignant behavior of pT2 gallbladder carcinoma.

MUC4 interacts with ErbB2 in human gallbladder carcinoma : Potential pathobiological implications

Muc4 interacts with erbB2 and potentiates tumourigenesis and/or tumour growth. The expression of MUC4, the interaction of MUC4 with erbB2 and the status of erbB2 signalling in human gallbladder carcinomas were determined in order to gain a better understanding of the pathobiology. The expression levels of MUC4 protein and mRNA were increased in specimens of gallbladder carcinoma. Immunoprecipitation experiments showed an interaction between MUC4 and erbB2. This interaction was associated with the hyperphosphorylation of erbB2, MAPK and Akt and with the overexpression of cyclooxygenase-2. MUC4 was detected on the apical surface of cancerous epithelia and partially co-localised there with erbB2. Transfection experiments showed that MUC4 amplifies cell proliferation in the presence of heregulin through potentiating phosphorylation of erbB2 and its downstream signalling pathways. These findings suggest that MUC4 is up-regulated and interacts with erbB2 in human gallbladder carcinoma, and thereby support the potential implication of MUC4 in erbB2 activation.