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41.
Gastric adenocarcinoma is the second leading cause of cancer death worldwide. In Western series, survival rates vary widely and are generally lower than those reported from Eastern series. We performed a retrospective analysis of cases operated on at the Johns Hopkins Hospital over the past 18 years and collected data on demographics, tumor characteristics, pathologic stage, treatment methods, complications, survival time, and other relevant factors. Survival according to stage of disease, Lauren tumor type, tumorlocation,time period, andadministration of adjuvant therapy wasanalyzed, andresultswerecompared with those of other Western series. During this period, 436 patients with gastric adenocarcinoma underwent resection. We have shown a statistically significant association between survival and margin status, stage of disease, and Lauren tumor type. Overall 5-year survival was 26%, and 5-year survival after R0 resection was 33%. No significant difference was detected between survival and tumor location, time period of treatment, or administration of adjuvant therapy. Analysis of various Western series reveals major differences between the cohorts under study, such as stage of disease, extent of resection, tumor type, and tumor location. Many of the reported differences among Western series may be due to cohort differences, such as stage of disease, extent of resection, tumor type, and tumor location.  相似文献   
42.
A 60-year-old Japanese man was hospitalized because of urinary leakage from the anus on October 3, 1994. Retrograde urethrography detected a fistula between the bulbous urethra and the rectum. Urethrocystoscopy revealed a tumor on the urethrorectal fistula. Tumor biopsy showed a well differentiated adenocarcinoma. Cystourethrectomy with fistulectomy, and ileal conduit urinary diversion were performed. Pathological examination revealed primary adenocarcinoma in the fistula with invasion to the prostatic urethra and bladder wall. The patient showed no evidence of a recurrence as of August, 1996.  相似文献   
43.
目的 探讨血小板衍生生长因子 (PDGF)在肺鳞癌和肺腺癌中的表达及意义。方法 应用免疫组织化学技术观察了PDGF -A链和PDGF -B链在 42例肺鳞癌和 1 5例肺腺癌中的表达 ,并测定了它们在肺非特异性炎症组织中的表达。结果 PDGF -A链和PDGF -B链的表达主要定位于肿瘤细胞胞浆、血管内皮细胞及平滑肌细胞 ,炎症组织的肺泡上皮细胞及血管平滑肌细胞少量表达。PDGF -A链和PDGF -B链在肺鳞癌及肺腺癌中均有显著表达 ;PDGF的过度表达与肿瘤细胞的分化程度无关。结论 PDGF -A链和PDGF -B链的过度表达与肺鳞癌和肺腺癌有关 ;PDGF -A链和PDGF -B链的生物学特征可能有所不同 ,PDGF -B链与肿瘤微血管增生的关系可能更密切  相似文献   
44.
Early gastric cancer manifested as brain metastasis: Report of a case   总被引:1,自引:0,他引:1  
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis.  相似文献   
45.
应用流式细胞计对30例宫颈腺癌和混合癌细胞的DNA指数和细胞增殖周期各时相细胞分布比例进行分析,结果显示非整倍体肿瘤29例,占96.7%.流式细胞计在诊断恶性肿瘤方面是有价值的。细胞增殖周期比DNA指数对预后的估价更有意义.乳头型腺癌、分化I级的肿瘤,S+G2M比率最低,5年生存率最高.  相似文献   
46.
Purpose: A comprehensive pharmacokinetic study of leucovorin (5-formyltetrahydrofolate, 5-HCO-FH4) and its metabolites was conducted in plasma, liver and implanted tumor tissue from mice maintained on a low folic acid diet. While it has been previously demonstrated that the antitumor activity of fluorouracil (FU) can be potentiated by 5-HCO-FH4, the optimum time for administration of FU after 5-HCO-FH4, to maximally elevate the active folate metabolite methylenetetrahydrofolate in tumor has not been established. Human plasma studies have defined the pharmacokinetics of circulating 5-HCO-FH4 and its metabolites, but comparison with human tumor accumulation has not been practicable because of sampling difficulties. As an alternative, a mouse model system, based on low dietary folic acid, was used to evaluate plasma, liver and implanted tumor reduced folates after administration of 5-HCO-FH4.Methods: Plasma and tissue samples were collected from folate-deplete mice over a 12-h period after intraperitoneal administration of 90 mg/kg [R, S ] 5-HCO-FH4. Reduced folates were evaluated using a ternary complex assay. Results: The time at which max‐imal accumulation of parent compound and all metabolites, except 5-methyltetrahydrofolate (5-CH3FH4), occurred in tumor was the same as in plasma. Alternatively, peak liver accumulation was delayed relative to plasma for all folates except 5-CH3FH4. Conclusions: The results suggest that mouse plasma accumulation of reduced folates, with the exception of 5-CH3FH4, can predict tumor accumulation. Hence, evaluation of human plasma folate accumulation may potentially provide a means to improve the timing of the administration of FU relative to 5-HCO-FH4 to achieve a superior therapeutic outcome. Received: 24 July 1996 / Accepted: 29 October 1996  相似文献   
47.
Adenoma malignum (AM) is a rare variant of cervical adenocarcinoma with an unfavorable prognosis despite radiation therapy, surgery, or chemotherapy either alone or in combination. Hitherto, however, the effectiveness of hormonal therapy for this condition has not been evaluated. We report on a patient with cervical AM treated with progesterone before surgery. The progesterone therapy resulted in a complete clinical response and partial surgical response. Later on the treatment was changed to tamoxifen because of side effects of the progesterone treatment. The patient is still without evidence of disease 42 months after the start of the hormonal therapy. The progesterone receptor analysis on the biopsy was clearly positive. This is, to our knowledge, the first case of an AM responsive to hormonal treatment. Furthermore, this is the first case of an AM with bone metastases at the time of primary diagnosis.  相似文献   
48.
Summary The combination of tumor necrosis factor (TNF) and etoposide (ETP) was evaluated for potential cytotoxic efficacy against a human renal cell carcinoma xenograft using an in vivo assay employing an athymic mouse host with tumor implanted a the subrenal capsule site. Both antitumor efficacy (relative survival or RTS) and toxicity (weight loss) of TNF and ETP alone and in combination were evaluated. While TNF and ETP alone were mildly inhibitory (RTS 90% and 71%, respectively), the combination caused marked tumor inhibition (45% of controls). Host toxicity encountered with the combination did not exceed the toxicity associated with ETP alone, suggesting that the therapeutic index may have been augmented. It is concluded that enhanced antitumor activity without substantial augmentation of toxicity is observed with this combination, providing a rationale for further evaluation of tumor necrosis factor-based regimens for the treatment of advanced renal carcinoma.Supported by a Merit Review grant, VA Medical Research Service, Durham, NC 27710, USA  相似文献   
49.
Background Gene therapy by adenovirus-mediated wild-type p53 gene transfer has been shown to inhibit lung cancer growth in vitro, in animal models, and in human clinical trials. The antitumor effect of selective cyclooxygenase (COX)-2 inhibitors has been demonstrated in preclinical studies. However, no information is available on the effects of p53 gene therapy combined with selective COX-2 inhibitor on COX-2 gene expression and growth inhibition of human lung cancer cells. Methods We evaluated the effects of recombinant adenovirus-p53 (Adp53) gene therapy combined with selective CADX-2 inhibitor on the proliferation, apoptosis, cell cycle arrest of human lung adenocarcinoma A549 cell line, and the effects of tumor suppressor exogenous wild type p53 on COX-2 gene expression. Results Ad-p53 gene therapy combined with selective COX-2 inhibitor celecoxib shows significant synergistic inhibition effects on the growth of human lung adenocarcinoma A549 cell line. Exogenous p53 gene can suppress COX-2 gene expression. Conclusions Significant synergistic inhibition effects of A549 cell line by the combined Ad-p53 and selective COX-2 inhibitor celecoxib may be achieved by enhancement of growth inhibition, apoptosis induction and suppression of COX-2 gene expression. This study provides first evidence that the administration of p53 gene therapy in combination with COX-2 inhibitors might be a new clinical strategy for the treatment or prevention of NSCLC.  相似文献   
50.
从2105例胃癌癌旁组织中找出微小腺癌31例(〈0.1cm),观察其组织发生的特征,发现胃腺癌的发生有8种形式:①腺颈部干细胞癌变;②表面上皮癌变;③腺上皮癌变;④肠化生上皮癌变;⑤微腺囊癌变;⑥溃疡边缘上皮癌变;⑦扁平腺瘤癌变;⑧贲门交界处柱状上皮癌变。  相似文献   
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