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Masaki Kitajima

Publications and source records attributed to Masaki Kitajima.

At least 37 records · Page 2Linked to original sources
PubMed2006

Gallbladder carcinoma with osteoclast-like giant cells.

Extraskeletal tumors containing multinucleated, osteoclast-like giant cells (OGCs) are uncommon. These neoplasms are most frequently reported in the breast and pancreas. Recently, some authors have suggested that carcinomas containing OGCs may represent a distinct clinicopathological entity with a more favorable prognosis. Occurrence in the gallbladder is extremely rare, with only one previous case. We report here on an additional case of gallbladder carcinoma with an infiltrate of OGCs. A 72-year-old woman presented with postprandial abdominal pain and was found to have a mass in the body of the gallbladder with direct liver invasion. Histological examination showed an adenosquamous carcinoma with an infiltrate of benign OGCs. Immunohistochemical analysis demonstrated that the giant cells were of histiocytic origin. The patient survived for 6 years without evidence of recurrence. This case adds to a small body of literature on gallbladder carcinoma with OGCs. Further studies are required to clearly define the prognostic significance of these giant cells in gallbladder cancer and the differences between adenosquamous carcinoma with OGCs and other gallbladder carcinomas (such as adenocarcinoma and squamous cell carcinoma) with those cells.

Aged↗
PubMed2006

A solid pseudopapillary tumor arising from the greater omentum followed by multiple metastases with increasing malignant potential.

Solid pseudopapillary tumor is a rare, indolent neoplasm almost exclusively seen in the pancreas. We describe an unusual case of solid pseudopapillary tumor arising in the greater omentum of a 45-year-old man with subsequent multiple liver metastases and peritoneal dissemination. The patient underwent a total of ten laparotomies and died of unresectable disease 8 years after the initial presentation. Microscopically, the primary tumor and the relapsed tumors consistently exhibited identical growth patterns, which were characterized by solid sheets intermingling with pseudopapillary arrangements of uniformly small cells. Immunohistochemical staining was diffusely positive for vimentin and focally positive for alpha-1-antitrypsin. These features were compatible with those of conventional pancreatic solid pseudopapillary tumors. We also performed quantitative evaluation of Ki-67 immunoreactivity and mitotic figures, which indicated malignant transformation of this extremely rare tumor. This is the first detailed report of solid pseudopapillary tumor arising outside the pancreas complicated by repetitive liver metastases and peritoneal carcinomatosis, suggesting the existence of a more lethal subgroup of tumors.

Biomarkers, Tumor↗
PubMed2006

Metastatic gastric cancer from malignant fibrous histiocytoma: report of a case.

Metastatic gastric cancer originating from malignant fibrous histiocytoma (MFH) is rare. To our knowledge, only nine other cases have been reported. We report the case of a 75-year-old man who underwent a distal gastrectomy for advanced gastric carcinoma, 2 years after resection of an MFH from the left side of his back. We based our preliminary diagnosis of primary advanced gastric carcinoma on the results of a preoperative biopsy specimen, which suggested either poorly differentiated adenocarcinoma or nonepithelial cell-originating malignant disease-like lymphoma. The resected stomach contained a large ulcerative tumor in the antral section, which was positive for Kp-1 and S-100 by immunohistochemical staining, confirming a pathological diagnosis of metastatic MFH of the stomach. He died of recurrence in the mediastinal space 16 months after the gastrectomy. Our analysis of this and previous cases suggests that resection may be inappropriate for patients with gastric metastasis of MFH because of the extremely high malignant potential of this tumor.

Aged↗
PubMed2006

Inflammatory pseudotumor of the liver masquerading as hepatocellular carcinoma after a hepatitis B virus infection: Report of a case.

We report a rare case of hepatic inflammatory pseudotumor (IPT) after a hepatitis B virus (HBV) infection. Early contrast enhancement on computed tomography (CT) with a washout phenomenon at the delayed phase, and depleted Kupffer cell function on superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) suggested hepatocellular carcinoma (HCC). However, the lack of a tumor capsule, absence of liver cirrhosis, and normal serum levels of alpha-fetoprotein and PIVKA-II (protein induced by vitamin K absence; descarboxyprothrombin) contradicted this diagnosis. We excised the tumor to exclude malignancy, and the histopathological diagnosis was IPT. Recent evidence suggests that this entity has changed from an extremely rare pathology to an established disease. Thus, IPT should be considered in the differential diagnosis of a liver mass with an infectious-inflammatory antecedent. Although surgery is not mandatory, surgical removal is recommended if there is a possibility of malignancy. Further investigations are warranted to elucidate the mechanisms of IPT developing after an HBV infection.

Angiography↗
PubMed2006

Sentinel lymph node mapping with GI cancer.

Precise evaluation of lymph node status is one of the most important factors in determining clinical outcome in treating gastro-intestinal (GI) cancer. Sentinel lymph node (SLN) mapping clearly has become highly feasible and accurate in staging GI cancer. The lunchtime symposium focused on the present status of SLN mapping for GI cancer. Dr. Kitigawa proposed a new strategy using sentinel node biopsy for esophageal cancer patients with clinically early stage disease. Dr. Uenosono reported on whether the SLN concept is applicable for gastric cancer through his analysis of more than 180 patients with cT1-2, N0 tumors. The detection rate was 95%, the false negative rate of lymph node metastasis including micro-metastasis was 4%, and accuracy was 99% in gastric cancer patients with cT1N0. Dr. Bilchik recommended the best technique for identifying SLNs in colorectal cancer: a combination of radiotracer and blue dye method, emphasizing that this technique will become increasingly popular because of the SLN concept, with improvement in staging accuracy. He stressed that this novel procedure offers the potential for significant upstaging of GI cancer. Dr. Saha emphasized that SLN mapping for colorectal cancer is highly successful and accurate in predicting the presence or absence of nodal disease with a relatively low incidence of skip metastases. It provided the "right nodes" to the pathologists for detailed analysis for appropriate staging and treatment with adjuvant chemotherapy. Although more evidence from large-scale multicenter clinical trials is required, SLN mapping may be very useful for individualizing multi-modal treatment for esophageal cancer and might be widely acceptable even for GI cancer.

Antineoplastic Agents↗
PubMed2006

Can endoscopic ultrasonography differentiate nonneoplastic from neoplastic gallbladder polyps?

The present study aimed to clarify the endoscopic ultrasonography (EUS) features of nonneoplastic (cholesterol polyps and adenomyomatosis) and neoplastic (adenoma and adenocarcinoma) gallbladder polyps and to evaluate the effectiveness and limitation of EUS in the differential diagnosis of these lesions. We retrospectively compared EUS images with histologic findings in 29 surgical cases with gallbladder polyps with a diameter of 10 to 20 mm. Those cases were indicated for surgery based on the findings of a sessile appearance, a solitary lesion, low echogenicity, and/or a lobulated surface. Six of 10 cholesterol polyps were atypically seen as partially or completely hypoechoic due to predominant proliferation of glandular epithelia. Nine of 10 cholesterol polyps demonstrated an aggregation of hyperechoic spots, which represented multiple granules of cholesterosis. All adenomyomatoses (n = 10) showed multiple microcysts, which corresponded to proliferated Rokitansky-Aschoff sinuses. However, three of nine neoplastic lesions (three adenomas and six adenocarcinomas) showed one of these signs due to concomitant cholesterosis (n = 2) or proliferated Rokitansky-Aschoff sinuses (n = 1). In conclusion, 69% (20/29) of gallbladder polyps larger than 10 mm that were preoperatively suspected of malignancy were nonneoplastic. An aggregation of hyperechoic spots and multiple microcysts are considered to be important predictive factors for cholesterol polyps and adenomyomatosis, respectively. However, we should caution that these findings can also occur in neoplastic polyps when they contain a concomitant nonneoplastic component (cholesterosis or proliferated Rokitansky-Aschoff sinuses).

Adenocarcinoma↗
PubMed2006

Successful liver transplantation across the ABO incompatibility barrier in 6 cases of biliary atresia.

BACKGROUND: The problem of ABO-incompatible liver transplantation still remains unsolved in older children. In this article, we report on our experience of 6 successful ABO-incompatible liver transplantations in patients with biliary atresia. MATERIAL AND METHODS: Six patients (ABO incompatibility type A-->O:1 case, B-->O:2 cases, A-->B:3 cases) were enrolled in this study; 3 patients were aged approximately 1 year and the other 3 ranged in age from 9 to 24 years at the time of transplantation. Each patient received perioperative plasma exchange, until the anti-donor blood-type antibody titers became less than 1:16, and also systemic multidrug immunosuppressive therapy (cyclophosphamide, prednisolone, and tacrolimus). We applied the protocol of intraportal infusion therapy (local administration of prostaglandin E(1), steroid, and gabexate mesilate via a portal vein catheter), splenectomy, and rituximab administration for the older group. RESULTS: Both the patient and graft survival rates remain at 100%, with the follow-up period of the patients ranging from 12 and 123 months. Acute cellular rejection occurred in 2 cases, and both were steroid sensitive. There was no incidence of humoral rejection. Although all cases developed viral infection, all recovered uneventfully with the administration of antiviral agents. CONCLUSION: ABO-incompatible liver transplantation can be performed with a low risk of humoral rejection or late biliary complications using this combined antirejection strategy, even in older children.

ABO Blood-Group System↗
PubMed2006

Reconstructive surgery for segmental arterial mediolysis involving both the internal carotid artery and visceral arteries.

Segmental arterial mediolysis (SAM) is a rare, nonatherosclerotic, noninflammatory arteriopathy. A 52-year-old man with sudden hemiparesis of the right side was found to have an aneurysm of the left internal carotid artery and concomitant multiple aneurysms of the extrahepatic, celiac, and superior mesenteric arteries. Reconstructive operations using autologous vein graft were performed to treat the aneurysms. The histopathology analyses of resected arterial and aneurysmal specimens showed characteristics consistent with SAM. To our knowledge, a successfully treated case of SAM affecting both the carotid artery and visceral arteries has not previously been described.

Aneurysm↗
PubMed2006

Large renal artery aneurysm in Takayasu arteritis.

Takayasu arteritis (TA), a primary arteritis of unknown cause, commonly affects the aorta and its main branches. Most patients with TA have stenotic or occlusive changes; aneurysmal degeneration is relatively rare, and renal artery aneurysms are extremely rare. We observed a fusiform, 7-cm renal artery aneurysm in a 57-year-old man with TA who had been followed up for 17 years. The patient underwent nephrectomy and resection of the aneurysm. Histologic examinations of resected specimens of the lesion showed characteristics typical of TA.

Aneurysm↗
PubMed2006

Gastroesophageal carcinoma: individualized surgical therapy.

During the twentieth century, surgical management of gastroesophageal carcinoma was developed by an establishment of standard procedures with lymph node dissection according to the metastatic distribution. The "fear" of invisible micrometastasis caused surgeons to perform more aggressive resection with lymphadenectomy to control the disease locally. Although several promising results of extensive lymph node dissection have been reported, the prognostic benefits of extensive surgery have not been proven by prospective randomized trials. A novel technology to detect micrometastasis without extensive surgical resection is required to gastroesophageal carcinoma. The lymphatic mapping technique is one of the attractive candidates for a novel tool to approach this issue.

Esophageal Neoplasms↗
PubMed2006

Operative indications for relatively small (2-5 cm) gastrointestinal stromal tumor of the stomach based on analysis of 60 operated cases.

BACKGROUND: Removal of the primary lesion with a clear operative margin is the standard treatment for gastrointestinal stromal tumor (GIST) of the stomach. However, there are few reports on the operative indications for relatively small GIST. METHODS: Clinicopathologic features and survival data of all 60 patients with GIST of the stomach treated at Keio University Hospital from 1993 to 2004 were analyzed. Laparoscopic wedge resection was used as the primary procedure for tumors between 2 to 5 cm. Tumors larger than 5 cm were resected by laparotomy or laparoscopy-assisted operation. RESULTS: Thirty-five lesions (58.3%) were resected by laparoscopic wedge resection, 3 by laparoscopic operation with a small skin incision and 22 by conventional open procedures. The mean size of the tumors was 42.5 mm, with a range of 18 to 150 mm and a median value of 35.5 mm. All operative margins were clear, but 1 patient had liver metastases at the time of resection of the primary lesion. The median follow-up period was 53 months and the 5-year disease-free survival rate (DFS) was 96.1%. No local recurrence or distant metastasis was encountered in patients with tumors smaller than 4 cm. A statistically significant correlation was observed between tumor size and mitotic count in this cohort (P = .010). Tumors from the intermediate- (n = 14) and high-risk (n = 10) groups as classified by the Risk Assessment Classification showed significantly worse DFS than the low-risk and very low risk group (n = 35) (89.9% vs 100% in 5-year DFS, P = .045). Even among tumors smaller than 3 cm, 2 of 14 cases (14.3%) were classified into the intermediate-risk group. CONCLUSIONS: Although a prospective randomized trial remains to be performed, this study provides additional evidence suggesting that the early removal of GIST, at 5 cm or less in size, provides better DFS than later removal of the tumor at a larger size.

Adult↗
PubMed2006

Treatment of fulminant hepatic failure in rats using a bioartificial liver device containing porcine hepatocytes producing interleukin-1 receptor antagonist.

Fulminant hepatic failure (FHF) is a serious clinical condition that is associated with high mortality. There is evidence that FHF is an inflammatory disease, which is supported clinically by elevated serum levels of cytokines. In an effort to develop hepatocytes with additional functions for use in our bioartificial liver (BAL) device, we focused on interleukin-1 (IL-1) blockade as a therapeutic modality. Primary porcine hepatocytes were isolated from the livers of miniature swine and then transfected with an adenoviral vector encoding human interleukin-1 receptor antagonist (AdIL-1Ra). The transfected hepatocytes secreted human IL-1Ra. These transfected hepatocytes were incorporated into a flat-plate BAL device to evaluate their efficacy in treating D-galactosamine (GalN)- induced FHF in a rat model. After extracorporeal perfusion with the BAL device containing the transfected hepatocytes, there were significant reductions in the plasma levels of hepatic enzymes (aspartate aminotransferase and alanine aminotransferase) and cytokines (IL-1 and IL-6), indicating a beneficial effect. Animal survival was significantly improved in the treated group compared to the control group. These experiments demonstrate that combining inflammatory cytokine blockade with a functional BAL device may be an effective therapeutic option in the treatment of FHF.

Adenoviridae↗
PubMed2006

Increased serum and hepatic tissue levels of interleukin-18 in patients with fulminant hepatic failure.

BACKGROUND: Fulminant hepatic failure is a serious clinical condition associated with a high mortality rate. Interleukin (IL)-18 is a pro-inflammatory cytokine that is associated with several inflammatory diseases. The purpose of the present paper was therefore to investigate whether IL-18 is elevated in patients with fulminant hepatic failure. METHODS: Serum levels of IL-18 were measured in patients with fulminant hepatic failure before and after liver transplantation. Native liver tissue samples were collected and the tissue levels of IL-18 were determined. Liver tissues were stained immunohistochemically with antihuman IL-18 antibody. The serum levels of IL-1beta, IL-6, IL-8, IL-12, interferon-gamma, and tumor necrosis factor-alpha were also determined in patients with fulminant hepatic failure before and after liver transplantation. RESULTS: Elevated levels of IL-18 in serum and hepatic tissue were observed in patients with fulminant hepatic failure. Native liver tissue samples were immunohistochemically positive for IL-18. Interleukin-18 levels were markedly reduced after liver replacement. No other inflammatory cytokines were substantially elevated in patients with fulminant hepatic failure. CONCLUSION: The serum levels of IL-18 levels are elevated much more than those of other cytokines in patients with fulminant hepatic failure.

Case-Control Studies↗
PubMed2006

Antiangiogenic agent SU6668 suppresses the tumor growth of xenografted A-431 cells.

SU6668 is an antiangiogenic agent that acts as a tyrosine kinase inhibitor for the vascular endothelial growth factor (VEGF) receptor. We treated xenografted A-431, a human squamous cell carcinoma cell line, with SU6668 to investigate the efficacy of tumor dormant therapy using angiogenesis inhibitors for patients with squamous cell carcinoma. A-431 cells were transplanted into severe combined immunodeficient (SCID) mice. The treatment group was given SU6668 at a dose of 200 mg/kg orally twice a day for 3 weeks; the control group was given only the vehicle in the same manner and intervals. SU6668 suppressed tumor growth of A-431 cells in the xenograft model. Furthermore, tumor volume and the number of vessels were significantly reduced in the treatment group compared with those of the control. No significant differences in body weight were found between the treatment and control groups, and no toxic reactions occurred during the experiment. We concluded that this agent was safe, efficient and potentially useful for the treatment of patients with squamous cell carcinoma.

Angiogenesis Inhibitors↗
PubMed2006

[The evolving role of endocrine therapy for breast cancer].

The indirect comparison of LHRH agonist with tamoxifen showed similar efficacy in the adjuvant treatment of premenopausal endocrine-responsive breast cancer patients. Furthermore, LHRH agonist is as effective as cyclophosphamide, methotrexate and 5-fluorouracil chemotherapy. Data concerning combination of LHRH agonist with third-generation aromatase inhibitors are still lacking. Moreover, duration of therapy with LHRH agonist is still a matter of debate. In randomized clinical trials, each of the third-generation aromatase inhibitors (AIs) has demonstrated efficacy in the adjuvant treatment of postmenopausal women with receptor' -positive tumors. Anastrozole has been shown to improve disease-free survival when compared with tamoxifen, letrozole has been shown to further reduce the rate of breast cancer events when given as extended adjuvant therapy in women completing between 4.5 and 6 years of tamoxifen, and exemestane has been shown to improve disease-free survival when substituted for tamoxifen after an initial 2-3 years of adjuvant therapy. Although long-term follow-up for safety and overall survival continues in each of these trials, currently available data suggest that an AI should now be included as part of adjuvant endocrine therapy for the great majority of receptor-positive postmenopausal patients.

Aromatase Inhibitors↗
PubMed2006

Antitumor effect of combination of S-1 and docetaxel on the human breast cancer xenograft transplanted into SCID mice.

In vivo experiments were performed on breast cancer xenografts to examine whether the combination therapy with S-1, an oral dihydrouracil dehydrogenase (DPD) inhibitory fluoropyrimidine, plus docetaxel functions as an additive/synergistic modulator in tumor growth. The human breast cancer xenograft, MDA-MB-435SHM, was inoculated into SCID female mice. The tumor growth and thymidylate synthase (TS)/DPD activity of tumors treated with the agents were investigated. The T/C value (relative mean tumor weight of the treated group/relative tumor weight of the control group) of the group treated with docetaxel, S-1 and combination therapy were 45.3, 63.1 and 29.8%, respectively; suggesting the positive antitumor effects of the combination therapy in particular. In addition, significant down-regulation of DPD activity was also observed in the tumors treated with S-1, docetaxel and their combination. Down-regulation of the DPD activity of the tumors is also considered to be correlated with the antitumor effect of the treated groups, suggesting its influence on the synergistic effect of the combination therapy.

Animals↗
PubMed2006

[A recent trial of chemo-radiation with S-1 against gastric cancer].

A recent development of novel anticancer agents like S-1, CPT-11 or taxanes has improved a therapeutic outcome for advanced gastric cancer, while conventional anticancer agents showed less anticancer effect against gastric cancer. The present main drug in Japan is S-1, which is easily used for outpatient with a high efficacy rate and low toxicity, also shows better effect in combination with other anticancer drugs than S-1 alone. In the present article, we demonstrated significant meaning of additional radiation therapy with anticancer drugs like S-1. With novel anticancer drugs like S-1, we will expose a clinical advantage and appropriateness for chemo-radiation therapy against gastric cancer discussed in the present references according to chemo-radiation therapy. Although chemo-radiation therapy has been recognized as one of the standard therapies for gastric cancer in Western countries, radiation therapy was selected in Japan for palliation therapy of recurrent disease or a terminal cancer to improve patients' QOL. On the other hand, we demonstrated in our trial of chemo-radiation therapy with S-1/low-dose CDDP/radiation (TSLDR), which was applied to initial treatment against highly advanced Stage IV gastric cancer and revealed the usefulness of the regimen in anticancer effect and toxicity. In addition, chemo-radiation therapy including novel anticancer agents like S-1 will be discussed based on various kinds of view points, expecting a better clinical outcome of multimodal therapies against advanced gastric cancer.

Adult↗