Urgent colonoscopy is not necessary in case of colonic diverticular bleeding without extravasation on contrast-enhanced computed tomography.

BACKGROUND AND AIMS: Acute lower gastrointestinal bleeding (ALGIB) increase with age and the administration of antiplatelet drugs. Colonic diverticular bleeding (CDB) is the most common cause of ALGIB, and endoscopic hemostasis is an effective treatment for massive CDB. But in patients without extravasation on contrast-enhanced computed tomography (CECT), the efficacy of urgent colonoscopy (UCS) is controversial from the point of the clinical course, including rebleeding rate. We aimed to establish a potential strategy including UCS for CDB patients without extravasation on CECT. PATIENTS AND METHODS: Patients from two centers treated for CDB without extravasation on CECT between July 2014 and July 2019 were retrospectively identified (n = 282). Seventy-four underwent UCS, and 208 received conservative management. We conducted two analyses. The first analysis investigates the risk factors of rebleeding rate within 5 days after administration (very early rebleeding), and no UCS (NUCS) was not the independent factor of the very early rebleeding. The second analysis is whether UCS positively influenced the clinical course after hospitalization. RESULTS: The prevalence of very early rebleeding and early rebleeding (6-30 days from admission), patients requiring blood transfusion within 0-5 days and 6-30 days post-admission, and duration of hospitalization were examined as clinical course factors between UCS and NUCS group. There was no significant difference between the UCS and non-UCS groups in the clinical course factors. UCS for the CDB patients without extravasation was not improved rebleeding rate and clinical course. CONCLUSIONS: UCS is not necessary in case ofCDB patient without extravasation on CECT.

Relationships between body mass index and constipation, gastroesophageal reflux disease, stool forms based on the Bristol Stool Form Scale, and education level: results from an internet survey in Japan.

Detailed evaluations of body mass index (BMI) and stool form based on the Bristol Stool Form Scale (BSFS) in individuals with constipation, gastroesophageal reflux disease (GERD), and concomitant constipation and GERD have not been performed in Japan. This study was an internet survey conducted to examine the relationships between BMI and constipation, GERD, stool forms based on the BSFS, and education level. This internet-based survey recruited participants from general public survey panels. 10,000 individuals meeting the eligibility criteria were enrolled. Questions included demographics, medical data, and assessments based on validated measures for constipation and GERD. BMI was significantly lower in males with versus without constipation. BMI was significantly higher with GERD both males and females. Mean BMI increased from the BSFS-1/2 group through the BSFS-3/4/5 to the BSFS-6/7 groups in both sexes. BMI was highest in individuals with a maximum education level of junior high school and second highest in individuals completing high school. This is the first real-world survey that closely examines the relationship between BMI and stool forms of individuals in Japan. When the BMI increased, stool forms varied from hard to watery in Japanese people. BMI was related with education level in Japan. (Trial registration: UMIN000039688).

A case report of contrast-enhanced harmonic ultrasonography for the diagnosis of an esophageal duplication cyst.

A 54-year-old man was referred to our hospital because of a suspected esophageal submucosal tumor on upper gastrointestinal radiography. Contrast-enhanced computed tomography showed a 52 mm homogeneous mass attached to the lower thoracic esophagus. Esophagogastroduodenoscopy revealed a 50 mm submucosal tumor in the lower esophagus, and endoscopic ultrasonography (EUS) showed a continuous hypoechoic lesion in the esophageal muscularis propria. Contrast-enhanced harmonic EUS revealed a non-echogenic area. T1 and T2 magnetic resonance imaging revealed a high-signal lesion. Based on imaging studies, an esophageal duplication cyst was diagnosed. Although asymptomatic, the patient underwent video-assisted thoracic surgery because of the possibility of rupture and the appearance of symptoms due to a future infection or enlargement, although this was not noted before. In our case, the esophageal duplication cyst appeared as a hypoechoic mass, requiring differentiation from submucosal tumor other than the cyst. Histologically, the cyst was covered by two layers of muscle covered by the chorioepithelial columnar epithelium. EUS fine-needle aspiration is effective in diagnosing submucosal tumor but also carries the risk of infection. Contrast-enhanced ultrasonography was used in this case to observe the interior and reach a preoperative diagnosis. Contrast-enhanced harmonic EUS appears to be effective in examining the interior of submucosal tumor lesions noninvasively.

A case of ulcerative colitis-related postoperative enteritis treated with granulocyte and monocyte apheresis.

A 46-year-old man, receiving continuous steroid therapy for refractory ulcerative colitis with an insufficient response to anti-tumor necrosis factor-α therapy, presented with left buttock pain. He was diagnosed with steroidal left femoral head necrosis, and total proctocolectomy with permanent ileostomy was performed. At 6 months postoperatively, the patient developed general fatigue, abdominal pain, and severe ileostomy diarrhea. Computed tomography revealed continuous intestinal edema from the descending duodenal leg to the upper jejunum. Gastrointestinal endoscopy revealed deep ulcers, coarse mucosa, and duodenal erosion. Based on clinical progress, findings, and pathology, the patient was diagnosed with ulcerative colitis-related postoperative enteritis. Although 5-aminosalicylic acid treatment was initiated, his symptoms persisted, bloody diarrhea from colostomy was observed. Subsequently, granulocyte and monocyte apheresis treatment was added. Symptoms and endoscopic findings improved with granulocyte and monocyte apheresis. Azathioprine was introduced as maintenance therapy, and no sign of recurrence was observed. Although ulcerative colitis-related postoperative enteritis has no definitive treatment, granulocyte and monocyte apheresis may be considered for initial treatment.

Small-Intestinal Metastasis from Lung Carcinoma.

A 62-year-old man was referred to our hospital because of abdominal pain. Computed tomography revealed an approximately 7-cm-diameter tumor in the left abdomen with metastatic lymph nodes, an approximately 1-cm-diameter round tumor in contact with the subclavian artery in the apical lobe of the right lung, and mediastinal lymph node enlargement in contact with the superior vena cava. Esophagogastroduodenoscopy and colonoscopy revealed no abnormalities. Double-balloon endoscopy revealed a whole circumferential ulcer in the jejunum approximately 20 cm from the ligament of Treitz. Biopsy analysis of an ulcer specimen revealed a poorly differentiated carcinoma. Immunohistochemical staining of the specimen showed that it was positive for thyroid transcription factor 1 and cytokeratin 7 and negative for cytokeratin 20, GATA-binding protein 3, caudal-type homeobox protein 2, and paired box 8. Positron emission tomography revealed positive findings in the small-intestinal tumor, nearby mesenteric lymph nodes, lymph nodes around the abdominal aorta, lung tumor, and mediastinal lymph node in the apical lobe of the right lung. Accordingly, the patient was diagnosed as having a lung carcinoma with small-intestinal metastasis (T1b, N3, M1c; cStage IVB). Pathological examination helped distinguish the primary small-intestinal tumor from the metastatic small-intestinal tumor and detect the tumor origin.

Gastric Plexiform Fibromyxoma Resected Using Nonexposed Endoscopic Wall-Inversion Surgery: A Case Report.

Gastric plexiform fibromyxoma is extremely rare. In our case, upper gastrointestinal endoscopy of a 41-year-old woman patient revealed a 1-cm submucosal tumor (SMT) in the greater curvature of the lower body of the stomach. On contrast-enhanced computed tomography, the tumor was hypervascular in the arterial phase with continuous enhancement in the post-venous phase. On endoscopic ultrasonography, it had a low echo pattern. The preoperative diagnosis was a gastric SMT with a rich vasculature; however because the biosy specimen did not contain tumor tissue, a malignant tumor could not be excluded. The patient underwent nonexposed endoscopic wall-inversion surgery (NEWS), and the tumor was completely resected. Immunohistochemical examination revealed that the tumor was positive for D2-40 and α-smooth muscle actin, but negative for c-kit, discovered on gastrointestinal stromal tumor-1, desmin, S100, Melan-A, signal transducer and activator of transcription 6, insulinoma-associated protein 1, CXCL13, ETS transcription factor, follicular dendritic cell, anaplastic lymphoma kinase, human melanoma black, h-caldesmon, and CD1a, 10, 21, 23, 31, 34, 68, and 163. Approximately, 1-2% of the tumor cell nuclei were Ki-67-positive. Finally, we diagnosed the tumor as a plexiform fibromyxoma. In conclusion, NEWS is an effective method for the treatment of SMTs with a diameter of <3 cm.

Phase II Prospective Study of Trastuzumab in Combination with S-1 and Oxaliplatin (SOX100) Therapy for HER2-Positive Advanced Gastric Cancer.

PURPOSE: The standard first-line treatment for human epidermal growth factor receptor type 2 (HER2)-positive advanced gastric cancer (AGC) is trastuzumab in combination with cisplatin and fluoropyrimidines. We evaluated the efficacy and safety of S-1 and oxaliplatin (100 mg/m2) (SOX100) combined with trastuzumab, a monoclonal antibody against HER2 for HER2-positive AGC. METHODS: In this single-arm, multicenter phase II study, patients with HER2-positive AGC received S-1 (80-120 mg per day) orally on days 1-14, oxaliplatin (100 mg/m2) intravenously on day 1, and trastuzumab (8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks) intravenously. The primary end point was 1-year survival rate. The secondary end points included overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and safety. RESULTS: A total of 25 patients from six centers were enrolled from December 2015 to March 2020. In the 25 patients evaluable for analysis, the 1-year survival rate was 70.8% [90% confidence interval (CI) = 55.5-86.1%], whereas the median OS, PFS, and ORR were 17.8 (95% CI 10.5-22.9) months, 7.6 (95% CI 5.0-10.9) months, and 75.0% (95% CI 53.3-90.2), respectively. Major grade 3/4 adverse events included anorexia (20%), anemia (16%), peripheral sensory neuropathy (16%), and diarrhea (15%). CONCLUSION: SOX100 combined with trastuzumab was effective with a favorable safety profile in patients with HER2-positive AGC.

The association among enterobacterial flora, dietary factors, and prognosis in patients with ulcerative colitis.

The role of enterobacterial flora in the onset and progression of inflammatory bowel diseases is a topic of considerable interest. Here, we assessed the association among enterobacterial flora, dietary factors, and ulcerative colitis (UC) progression. Forty-six patients with UC who were diagnosed as being in remission were enrolled. We collected each patient's stool sample one or two days before diagnostic colonoscopy. After colonoscopy, we observed the patients for one year and then retrospectively divided them into two groups: remission (n = 39) and relapse (n = 7) groups, depending on whether the relapse occurred during the follow-up period, and analyzed the relationship among patient characteristics, dietary factors, enterobacterial flora, and UC relapse. Overall, there were no significant differences in bacterial community populations between the remission and relapse groups, except that the order Lactobacillales was detected at a significantly higher rate in the relapse than in the remission group (100% vs 71.4%, p<0.05). Vitamin C intake was significantly higher in the remission than in the relapse group (p<0.05). Although there were no obvious differences in enterobacterial flora between the remission and relapse groups, there was a relationship among enterobacterial flora, diet, and UC progression. Given that the enterobacterial flora was only analyzed at the initiation of the study, we conclude that in future analyses, enterobacterial flora should be sampled at numerous time points to examine its role in UC progression. Further long-term longitudinal studies examining enterobacterial flora, dietary factors, and UC progression are also required.

Endoscopic resection of gangliocytic paraganglioma of the duodenum: a case report.

Duodenal gangliocytic paragangliomas are extremely rare. A 79-year-old woman underwent gastrointestinal endoscopy for screening prior to resection of gallbladder carcinoma. Gastrointestinal endoscopy revealed a 5-mm submucosal tumor in the second portion of the duodenum. Contrast-enhanced computed tomography revealed no tumor or metastasis. Endoscopic ultrasonography revealed low echo pattern of the tumor. Histopathological examination of the biopsy specimen revealed proliferation of three types of cells (epithelioid cells, spindle cells, and ganglion cells). Immunohistochemical examination revealed that the tumor was positive for S-100 and synaptophysin. The preoperative diagnosis was gangliocytic paraganglioma. The tumor was completely resected by endoscopic mucosal resection (EMR). In conclusion, an early stage of gangliocytic paraganglioma of the duodenum could be resected using EMR.

Gastric schwannoma with high accumulation on fluorodeoxyglucose-positron emission tomography resected by non-exposed endoscopic wall-inversion surgery.

Gastric schwannoma is a relatively rare tumor arising from Auerbach plexus in the muscle layer of the gastric wall, and constitutes 0.1% to 0.2% of all gastric tumors and 5% of benign non-epithelium-related gastric tumors. We report the case of a 49-year-old woman in whom upper gastrointestinal endoscopy revealed an approximately 2-cm submucosal tumor on the anterior wall of the fornix of the stomach. Contrast-enhanced computed tomography revealed a homogeneously enhanced lesion (~ 17 mm) in the upper third of the stomach as well as a lesion (~ 25 mm) on the left kidney that was strongly enhanced in the early phase. An 18F-fluorodeoxyglucose positron emission tomography scan revealed high accumulation that is characteristic of gastric tumors. The possibility of malignancy was not completely excluded, and the gastric tumor was resected by non-exposed endoscopic wall-inversion surgery. The patient was discharged with a good prognosis 5 days after surgery. In conclusion, non-exposed endoscopic wall-inversion surgery is a minimally invasive and effective method for resecting small gastric submucosal tumors (diameters < 3 cm) for which preoperative diagnosis is difficult.

Endoscopic Resection of a Pedunculated Cavernous Hemangioma of the Sigmoid Colon: A Case Report.

Hemangiomas are common benign tumors that usually occur on the head and neck in children. However, colonic hemangiomas are rare in clinical practice. Approximately 80% of colonic hemangiomas are of the cavernous type, and morphologically, ≥80% of colonic hemangiomas are sessile and semi-pedunculated. Notably, pedunculated colonic hemangiomas are rare. A 69-year-old woman presented with hematochezia and underwent colonoscopy, which revealed a soft pedunculated submucosal tumor (SMT) measuring 1.5 cm in diameter, in the sigmoid colon. The surface of the SMT resembled the surrounding normal colonic mucosa with regard to color and appearance, with multiple red patches. Narrow-band imaging revealed a few telangiectasias on the surface of the SMT. The lesion could not be definitively diagnosed based on endoscopic findings. Therefore, for more accurate diagnosis, the SMT was removed by snare polypectomy with electrocautery after clipping the basal portion of the tumor stalk for prophylactic hemostasis. Histopathological examination of the specimen revealed a cavernous hemangioma with a negative resection margin. We report a case of a pedunculated cavernous hemangioma of the sigmoid colon removed by snare polypectomy with electrocautery after clipping the basal portion of the tumor stalk for prophylactic hemostasis.

[Mucosa-associated lymphoid tissue lymphoma of the appendix concomitant with appendicitis:a case report].

An 82-year-old man with abdominal pain was admitted to our hospital. Laboratory tests revealed the following:white blood cells, 14300/µl;serum hemoglobin level, 12.9g/dl;serum C-reactive protein level, 0.38mg/dl;and negative anti-Helicobacter pylori immunoglobulin G test. Abdominal computed tomography revealed a tumor in the appendix along with multiple swollen lymph nodes. Colonoscopy revealed a submucosal tumor (SMT) of approximately 30mm in diameter with central ulceration. However, a tumor tissue specimen could not be obtained for biopsy;thus, the tumor could not be diagnosed. In esophagogastroduodenoscopy, abnormalities or gastric mucosal atrophy was not observed. A rapid urease test yielded negative results. Hence, endoscopic ultrasound-guided fine needle aspiration for the SMT was recommended;however, the patient preferred to undergo a definitive surgery to establish exact diagnosis. Therefore, right hemicolectomy and lymph node dissection (D3) were performed. Histopathologically, the resected tumor specimen showed atypical lymphocytes. Additionally, immunohistochemical evaluation demonstrated positive staining of the tumor cells for CD20 and BCL2 and negative staining for CD34, CD4, CD10, and BCL6. The tumor was finally diagnosed as a stage II2 mucosa-associated lymphoid tissue lymphoma (Lugano classification). Postoperatively, the patient received chemotherapy with four cycles of rituximab based on his age and activities of daily living.

Esophageal Leiomyosarcoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration Biopsy and Cured with Surgical Resection.

Esophageal leiomyosarcomas are rare. We herein present the case of an 82-year-old patient who underwent upper gastrointestinal endoscopy, which revealed a submucosal tumor of 30 mm in diameter that was in contact with the esophagus. Endoscopic ultrasound-guided fine needle aspiration biopsy was performed and the histopathological findings indicated esophageal leiomyosarcoma. Surgical resection was performed. On histopathological examination, the tumor was found to consist of spindle cells with deep chromatin nuclei. The tumor was finally diagnosed as esophageal leiomyosarcoma. We were able to diagnose early-stage esophageal leiomyosarcoma using endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA). EUS-FNA is mostly recommended as a diagnostic tool for esophageal submucosal tumors.

A Small Bowel Ulcer due to Clopidogrel with Cytomegalovirus Enteritis Diagnosed by Capsule and Double-Balloon Endoscopy.

We report the first case of small bowel ulcers due to clopidogrel in a 74-year-old man. He presented with diarrhea and melena after having been taking low-dose aspirin (LDA) and clopidogrel. There was no evidence of bleeding in the stomach, duodenum, or colon. Capsule endoscopy showed multiple ulcers and erosions in the small intestine. Double-balloon endoscopy revealed multiple ulcers throughout the ileum. Examination of the biopsy specimen showed cytomegalovirus infection. His LDA was discontinued and he was prescribed ganciclovir. However, the small bowel ulcers were aggravated. Therefore, clopidogrel was discontinued. The small bowel ulcers subsequently healed completely, forming scars.

Serum-Derived Hyaluronan-Associated Protein Is a Novel Biomarker for Inflammatory Bowel Diseases.

BACKGROUND/AIMS: We evaluated the role of serum-derived hyaluronan-associated protein (SHAP) in inflammatory bowel disease (IBD) pathogenesis and its potential as a novel IBD biomarker. METHODS: We studied the SHAP expression in a mouse model of colitis and in human intestinal samples of IBD and compared serum concentrations with normal controls. RESULTS: SHAP was expressed in the connective tissue derived from inflamed regions of the intestine. In mice, serum levels of SHAP-hyaluronic acid (SHAP-HA) were positively correlated with the histological damage of the colon (r = 0.566, p < 0.001). Serum concentration of SHAP-HA complex was significantly higher in patients with active ulcerative colitis than in those in remission, and this value was positively correlated with the erythrocyte sedimentation rate, serum level of tumor necrosis factor (TNF)-α, and endoscopic damage (r = 0.568, p < 0.001; r = 0.521, p < 0.001, and r = 0.641, p < 0.001). In patients with Crohn's disease, the serum SHAP-HA level correlated only with TNF-α (r = 0.630, p = 0.002). CONCLUSION: SHAP is a novel IBD biomarker that is related to disease activity in certain types of colitis, and it may affect disease pathogenesis. Future studies are needed to evaluate the therapeutic potential of this complex.

Antiviral and Antitumor Activity of Licorice Root Extracts.

BACKGROUND: In the search for anti-viral and antitumor substances from natural resources, antiviral and antitumor activities of licorice root extract and purified ingredients were investigated. MATERIALS AND METHODS: Viability of cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Antiviral activity was quantified by the selectivity index, defined as the ratio of the 50% cytotoxic concentration (CC50) to the 50% effective concentration against human immunodeficiency virus (HIV) or herpes simplex virus (HSV)-infected cells (EC50). The tumor specificity was calculated by the ratio of CC50 against human normal oral cells to that against human oral squamous cell carcinoma cell lines. Licorice flavonoids and lower molecular polyphenols were subjected to quantitative structure-activity relationship analysis. RESULTS: Alkaline extract of licorice root had higher anti-HIV activity than did water extracts, confirming our previous reports. On the other hand, water extract, especially the flavonoid-rich fraction, had higher anti-HSV activity than did the alkaline extract. The flavonoid-rich fraction was more cytotoxic against human oral squamous cell carcinoma cell lines compared to normal oral cells, suggesting their tumor-specific cytotoxicity. CONCLUSION: The present study suggests that water and alkaline extracts of licorice root exert different mechanisms of actions against these two viruses. Physicochemical properties, rather than the category of compounds, may be important in determining their anti-HSV activity.

A phase II prospective study of the trastuzumab combined with 5-weekly S-1 and CDDP therapy for HER2-positive advanced gastric cancer.

BACKGROUND: We evaluated the efficacy and safety of 5-weekly S-1 and cisplatin combined with trastuzumab, a monoclonal antibody against human epidermal growth factor receptor type 2 (HER2) for HER2-positive advanced gastric cancer (AGC). METHODS: This phase II study treatment consisted of S-1 (80-120 mg per day) orally on day 1-21, cisplatin (60 mg/m(2)) intravenously on day 8, and trastuzumab (8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks) intravenously. The primary end point was 1-year survival rate. The secondary end points included overall survival, progression-free survival (PFS), response rate (RR), and safety. RESULTS: A total 22 patients from seven centers were enrolled. In the 20 patients evaluable for analysis, the 1-year survival rate was 70 % (95 % confidence interval (CI) 49.9-90.1 %), and median survival time, PFS, and RR were 15.3, 7.5 months and 41.2 %, respectively. Major grade 3/4 adverse events were neutropenia (30 %), anorexia (30 %), leukopenia (25 %), fatigue (20 %), and anemia (15 %). CONCLUSIONS: Five-weekly S-1 and cisplatin combined with trastuzumab showed effective with favorable safety profile in patients with HER2-positive AGC.

Coexpression of organic anion-transporting polypeptides 1B3 and multidrug-resistant proteins 2 increases the enhancement effect of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid on hepatocellular carcinoma in magnetic resonance imaging.

AIM: We aimed to elucidate the relationship between the contrast enhancement effect of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) on magnetic resonance imaging (MRI) of hepatocellular carcinomas (HCC) and the expressions of hepatocyte transporters (i.e. organic anion-transporting polypeptide [OATP]1B3, multidrug-resistant protein [MRP]2 and MRP3) and to clarify the characteristics of HCC with an MRI high-contrast enhancement effect. METHODS: We retrospectively examined the relationship between the relative enhancement ratio (RER) of HCC, absolute and relative immunohistochemical staining scores of hepatocyte transporters, and histological differentiation of 22 HCC from 21 patients who had undergone preoperative Gd-EOB-DTPA-enhanced MRI. RESULTS: RER had a significant correlation with OATP1B3 expression according to the absolute and relative scores (P = 0.016 vs 0.0006). The RER of HCC with high OATP1B3 and MRP2 expression levels was higher than that of HCC with low OATP1B3 or MRP2 expression levels (P = 0.0003). The RER of HCC with higher OATP1B3 rates was greater than that of HCC with lower OATP1B3 rates (P = 0.0005). HCC histological differentiation showed a significant correlation with OATP1B3 expression and RER (P = 0.023 vs 0.0095). CONCLUSION: We found that coexpression of OATP1B3 and MRP2 influenced the high contrast enhancement of HCC on MRI.

Effect of three fluoride compounds on the growth of oral normal and tumor cells.

AIM: Comparative study of the growth inhibition by different types of fluoride compounds used in dentistry has been limited. We investigated the effects of sodium fluoride (NaF), diammine silver fluoride [Ag(NH3)2F] and 5-fluorouracil (5-FU) on the growth of eleven human normal and tumor cells in total. MATERIALS AND METHODS: Viable cell number was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis induction was evaluated by caspase-3 activation and DNA fragmentation. Fluoride was determined using a fluoride-specific electrode. RESULTS: All compounds had little or no growth stimulating effect (hormesis) on all cells. Ag(NH3)2F exhibited the highest cytotoxicity towards both normal and tumor cells. 5-FU had the selective cytostatic activity towards oral squamous cell carcinoma cell lines, whereas NaF was selectively cytotoxic towards glioblastoma cell lines. None of the compounds induced internucleosomal DNA fragmentation and only 5-FU induced slight activation of caspase-3 in an oral squamous cell carcinoma cell line (HSC-2). Cytotoxicity of fluoride compounds was not reduced by superoxide dismutase and catalase, reducing the possibility of the involvement of reactive oxygen species in the mechanism of action. Approximately 0.01-0.09% initially added NaF was recovered from the cells, whereas the cellular uptake of Ag(NH3)2F and 5-FU was below the detection limit. CONCLUSION: Cytotoxicity of fluoride compounds may not be directly linked to their tumor specificity nor to their apoptosis-inducing activity.

[A case of malignant tumor of the ascending part of duodenum with osteoclast-like giant cells].

Extraskeletal neoplasms with osteoclast-like giant cells are very rare. These tumors are most frequently reported in the breast and pancreas, and but rarely in other sites. We report a case of duodenal malignant tumor with osteoclast-like giant cells. The patient was a 76-year-old man who presented with vomiting. Computed tomography, magnetic resonance imaging, and gastrointestinal endoscopy revealed a giant tumor in the ascending part of duodenum. Biopsy specimens showed an undifferentiated malignant tumor with benign multinucleated giant cells. Immunohistochemical staining indicated that the tumor cells were reactive with vimentin, but not with epithelial markers or the other mesenchymal markers, and the multinucleated giant cells were reactive with CD68. Thus, we diagnosed a malignant tumor of the ascending part of duodenum with osteoclast-like giant cells. To the best of our knowledge, this is the first case of duodenal malignant tumor with osteoclast-like giant cells in Japan.