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51.
G207, a conditionally replicating herpes vector, efficiently kills human bladder cancer cells in vitro. To evaluate the therapeutic potential of G207, we have established three in vivo models similar to the clinical situation. In vivo, G207 was intraneoplastically, intravesically, or intravenously inoculated in nude mice. Intraneoplastic inoculation into subcutaneous tumor caused significant tumor growth inhibition. Intravesical inoculation of G207 also caused decreased tumor growth in an orthotopic human bladder cancer model. Furthermore, multiple intravenous inoculation markedly inhibited subcutaneous tumor growth. These results suggest that intravesical therapy with G207 is effective for localized bladder tumor, especially for carcinoma in situ (CIS), and intravenous therapy with G207 is promising for invasive or metastasized bladder tumor.  相似文献   
52.
The pancreatic endocrine tumors are uncommon neoplasms and are classified into non-functional and functional tumors. According to whether the secreted hormones are originated from pancreatic islet cells or not, the tumors are also classified into normotopic and ectopic tumors. Except for insulinoma, more than 60% of them reveal malignant behavior. The presence of endocrine tumor is diagnosed when patients develop a hormone-specific symptom, and the location of tumors are usually diagnosed by a combination of ultrasonography, computed tomography, magnetic resonance imaging and selective angiography. A somatostatin receptor scintigraphy is promising. Nevertheless, these examinations occasionally failed to precisely locate the tumors especially when they are very small and/or multiple. For such cases, both portal venous sampling and arterial provocation test are helpful.  相似文献   
53.
The medullary microenvironment of the thymus plays a crucial role in the establishment of self-tolerance through the deletion of self-reactive thymocytes and the generation of regulatory T cells. Crosstalk or bidirectional signal exchanges between developing thymocytes and medullary thymic epithelial cells (mTECs) contribute to the formation of the thymic medulla. Recent studies have identified the molecules that mediate thymic crosstalk. Tumor necrosis factor superfamily cytokines, including RANKL, CD40L, and lymphotoxin, produced by positively selected thymocytes and lymphoid tissue inducer cells promote the proliferation and differentiation of mTECs. In return, CCR7 ligand chemokines produced by mTECs facilitate the migration of positively selected thymocytes to the medulla. The cytokine crosstalk between developing thymocytes and mTECs nurtures the formation of the thymic medulla and thereby regulates the establishment of self-tolerance.  相似文献   
54.
Background  The effect of obesity on gastrectomy in patients with gastric cancer is controversial. The degree of abdominal fat increases the technical difficulty of abdominal surgery. This study examined the effect of visceral fat on total gastrectomy and risk factors associated with the formation of pancreatic fistula. Methods  Between February 2001 and April 2007, 191 patients with gastric cancer underwent total gastrectomy. The visceral fat area (VFA) was calculated from computed tomography (CT) scans taken at the level of the umbilicus using FatScan Software. Patients were divided into high- (≥100 cm2, n = 52) and low-VFA groups (<100 cm2, n = 139), and also into high- (≥25 kg/m2, n = 47) and low-BMI groups (<25 kg/m2, n = 144). Results  Blood loss and incidence of pancreatic fistula were significantly higher in the high- than low-VFA group. However, only blood loss was significantly different between the high- and low-BMI groups. VFA, blood loss, and splenectomy were identified as significant risk factors for pancreatic fistula formation on univariate analysis, and multivariate logistic regression analysis of these factors identified VFA (p = 0.0001) and splenectomy (p = 0.0014) as significant predictors of pancreatic fistula. Conclusions  VFA is a better indicator for pancreatic fistula formation after total gastrectomy than is BMI. Lymph node dissection must be performed carefully, especially in patients with visceral fat accumulation during total gastrectomy with splenectomy.  相似文献   
55.
Intraductal papillary-mucinous carcinoma (IPMC) is a recently recognized pancreatic tumor and this is the first report to present two patients with IPMC complicating tumor thrombi in the portal vein. Two women, a 74- and a 55-year-old, each revealed a round, cystic and well-demarcated tumor of the pancreas in an abdominal computed tomography (CT). However, the inner lumen of the splenic and portal veins was insufficiently stained during iv-infusion of the contrast medium, suggesting the presence of tumor thrombi. Owing to this information, the presence of tumor thrombus was investigated and correctly identified during laparotomy, and it was completely removable together with the primary pancreatic tumor. The resected tumors showed expansive growth because mucin and tumor tissues rose up when they were cut. Microscopically, the tumor was diagnosed as adenocarcinoma without ovarian-like stroma, and the final diagnosis of branch type of IPMC was made for the two patients. However, within one postoperative year, both patients developed liver metastasis. Although IPMC is known as having a lower potential for metastasis or invasion, the tumor thrombi can form when it reveals an expansive growth suggesting a high inner pressure. In addition, a higher possibility for subsequent liver metastasis should be anticipated after the tumor forms a thrombus in the portal vein.  相似文献   
56.
57.
BACKGROUND: Two different subtypes of papillary renal cell carcinoma (PRCC) have so far been identified, type-1 with small cells and pale cytoplasm and type-2 with large cells and eosinophilic cytoplasm. It has generally been accepted that type-1 tumors have favorable features in comparison with type-2 tumors, suggesting that these subtypes could be different clinicopathological entities, and, as a result, that the subtypes need to be characterized. Forty cases of PRCCs were reviewed, with special attention to the distinct clinicopathological difference and the response to cytokine therapy. METHODS: Thirty-five cases of PRCC diagnosed between January 1997 and August 2007 were reviewed. PRCCs were classified according to the criteria of Delahunt and Eble. RESULTS: Of these 40 patients, 20 and 20 were diagnosed to be type-1 and type-2 PRCCs, respectively. No lymphatic or vascular invasion or distant metastasis were observed in patients with type-1 PRCC. The nuclear grade in all type-1 PRCCs was low grade. The nuclear grade (P 相似文献   
58.
We report a case of inguinal lymphorrhea cured by Lipiodol lymphangiography. The patient was a 80-year-old female who underwent an abdomino-perineal resection with lateral pelvic lymph node dissection and inguinal lymph node extraction for anal canal cancer. Histologically, the tumor was a poorly differentiated adenocarcinoma and considered to be stage IV (a2, n3 (+), P0, H3, M (-), cur C) in the Japanese classification of colorectal cancer. We recognized a lot of lymph node metastases in dissected lateral pelvic lymph node and inguinal lymph node. By hepatic arterial infusion using 5-FU (1250 mg/body weekly), the liver metastases had a complete response after 15 courses. She noticed a left inguinal lymph node swelling and an elevation of serum CEA level (79.5 ng/mL) was observed. There was no evidence of recurrence except left inguinal lymph nodes. She underwent a left inguinal lymph node dissection. Serous discharge from a surgical site persisted despite of conservative therapy such as compression. She received lymphangiography using 8 mL of Lipiodol from left dorsum of foot. We found three lymph ducts heading to left groin and observed a lot of Lipiodol leakage from ducts. We determined not only the site of leakage but we also confirmed a gradual decrease and a complete stop of lypmphorrhea in 7 days after lymphangiography. Slight lymph edema of left lower extremity appeared but gradually relieved. Lymphangiography using Lipiodol helps determine the site of leakage and may be an effective therapeutic modality for treating refractory lymphorrhea.  相似文献   
59.
Peritoneal washing cytology during surgery was done in 745 patients with colorectal cancer. The positive washing cytology rate was 49/745 (6.6%). The peritoneal recurrence rates were 12/22 (54.5%) and 8/682 (1.3%) among patients with positive and negative peritoneal washing, respectively (p < 0.0001). The 5-year survival rate is 89.4% of the patients with positive cytology and 38.2% with negative cytology. The patients with positive cytology have a significantly lower survival rate than the negative one (p < 0.0001). Eleven patients of the positive cytology received intraperitoneal administration of MMC. Peritoneal dissemination occurred in 3/11 (27.3%) of the MMC treated group and 9/11 (81.8%) in the untreated group (p = 0.030). Our results indicated that intraperitoneal administration of MMC was an effective method of preventing peritoneal dissemination after resection of colorectal cancer.  相似文献   
60.
OBJECTIVE: To treat lumbar foraminal tumors, the chosen operative approach depends on the tumor location and size. Although total facetectomy and the combined intra- and extraspinal canal approach provide a wide operative field, facet fusion is required and the procedure is invasive. We report the successful removal of Eden type IV tumors using only the paraspinal approach without complete facetectomy. PATIENTS AND METHODS: We treated 4 patients with lumbar foraminal tumors. All were Eden type IV (neurofibroma, n=3; schwannoma, n=1) and all were removed via the paraspinal approach without total facetectomy and the intraspinal canal approach. Although total facetectomy was not needed to remove the intraforaminal component, phased foraminal expansion with a SONOPET (m&m Co., Ltd., Tokyo, Japan) device was required in all cases. Intratumoral decompression was performed with probe for tumor and PAL-I and EMG recordings were obtained with direct stimulation of the nerve root. RESULTS: All tumors were completely removed via only the paraspinal approach; neither total facetectomy and fusion, nor the addional intraspinal approach was required. There was no tumor recurrence or lumbar instability during the follow-up period. CONCLUSIONS: To remove the intraforaminal component of Eden type IV tumors, phased expansion of the foramen with a SONOPET and intratumoral decompression with CUSA and PAL-I are required and effective. Using these devices, this less invasive approach is useful for the treatment of patients with lumbar foraminal tumors of Eden type IV.  相似文献   
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