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41.
TNM: evolution and relation to other prognostic factors 总被引:6,自引:0,他引:6
Sobin LH 《Seminars in surgical oncology》2003,21(1):3-7
The TNM Classification describes the anatomic extent of cancer. TNM's ability to separately classify the individual tumor (T), node (N), and metastasis (M) elements and then group them into stages differs from other cancer staging classifications (e.g., Dukes), which are only concerned with summarized groups. The objectives of the TNM Classification are to aid the clinician in the planning of treatment, give some indication of prognosis, assist in the evaluation of the results of treatment, and facilitate the exchange of information. During the past 50 years, the TNM system has evolved under the influence of advances in diagnosis and treatment. Radiographic imaging (e.g., endoscopic ultrasound for the depth of invasion of esophageal and rectal tumors) has improved the accuracy of the clinical T, N, and M classifications. Advances in treatment have necessitated more detail in some T4 categories. Developments in multimodality therapy have increased the importance of the "y" symbol and the R (residual tumor) classification. New surgical techniques have resulted in the elaboration of the sentinel node (sn) symbol. The use of immunohistochemistry has resulted in the classification of isolated tumor cells and their distinction from micrometastasis. The most important challenge facing users of the TNM Classification is how it should interface with the large number of non-anatomic prognostic factors that are currently in use or under study. As non-anatomic prognostic factors become widely used, the TNM system provides an inviting foundation upon which to build a prognostic classification; however, this carries a risk that the system will be overwhelmed by a variety of prognostic data. An anatomic extent-of-disease classification is needed to aid practitioners in selecting the initial therapeutic approach, stratifying patients for therapeutic studies, evaluating non-anatomic prognostic factors at specific anatomic stages, comparing the weight of non-anatomic factors with extent of disease, and communicating the extent of disease data in a uniform manner. Methods are needed to express the overall prognosis without losing the vital anatomic content of TNM. These methods should be able to integrate multiple prognostic factors, including TNM, while permitting the TNM system to remain intact and distinct. This article discusses examples of such approaches. 相似文献
42.
Marin D Amaya K Casciano R Puder KL Casciano J Chang S Snyder EH Cheng I Cuccia AJ 《International psychogeriatrics / IPA》2003,15(4):385-398
BACKGROUND: Alzheimer's disease (AD) places a significant burden on health care systems worldwide. As new treatments are developed, their cost-effectiveness is often assessed to help health care professionals make informed decisions. In addition to the more common practice of assessing direct medical costs, indirect costs, including time spent in caregiving, should be evaluated. METHODS: This study examined the potential effects of the dual cholinesterase inhibitor rivastigmine (Exelon) on caregivers of patients with AD. Results from two 26-week, placebo-controlled trials have demonstrated the clinically relevant and statistically significant efficacy of rivastigmine (6-12 mg/day) compared to placebo, on cognition, activities of daily living, and global functioning. By delaying progression of AD, significant savings in caregiver burden are anticipated, as measured by time spent caregiving and its related costs. Data collected in a prospective, observational study of AD patients and their caregivers were used to establish the relationship between disease severity (based on Mini-Mental State Examination [MMSE] score) and time spent caregiving (according to the 5-item Caregivers Activity Survey score). A significant correlation was observed between the two scores (N = 43, r = -.56, p < .0001), demonstrating that more time for supervision from caregivers is required as the disease progresses. This finding was used to estimate the reduced caregiver burden resulting from the delay in disease progression that was demonstrated with use of rivastigmine. RESULTS: Over a 2-year period, the reduction in time spent in caregiving reached 691 hours for caregivers of patients with mild AD (MMSE score 21-30), resulting in a total savings of approximately 11,253 dollars. Treatment of patients with moderately severe AD was also evaluated. The trend was similar but the impact was less, suggesting an economic benefit to early therapy. CONCLUSION: Early diagnosis and a pharmacologic intervention that allows the patients to remain at home longer by delaying disease progression would have a beneficial impact on patients, caregivers, and payers, and should therefore be encouraged through initiatives designed to identify and treat patients early in the course of disease. 相似文献
43.
Tung KH Goodman MT Wu AH McDuffie K Wilkens LR Kolonel LN Nomura AM Terada KY Carney ME Sobin LH 《American journal of epidemiology》2003,158(7):629-638
Associations of reproductive factors with ovarian cancer may differ by histologic type. Data from a multiethnic, population-based, case-control study, conducted in Hawaii and Los Angeles, California, between 1993 and 1999, were used to assess this hypothesis. A structured questionnaire was administered to 558 histologically confirmed epithelial ovarian cancer cases and 607 population controls. Factors suppressing ovulation, including pregnancy and oral contraceptive use, were inversely associated with the risk of all histologic types. Nonmucinous but not mucinous tumors were significantly associated with menstruation years (odds ratio = 1.5 for the highest vs. the lowest quartile) and lifetime ovulatory cycles (odds ratio = 2.8 for the highest vs. the lowest quartile). Duration of breastfeeding (odds ratio = 0.4 for the highest vs. the lowest quartile) was significantly and inversely related to nonmucinous tumors but not to mucinous tumors. Among all tumor types, endometrioid tumors were the most strongly related to pregnancy and tubal ligation, while clear cell tumors were the only type that was associated with noncontraceptive hormone use. The risk factors were similar for borderline and invasive tumors, except for age at diagnosis. Mucinous tumors, both borderline and invasive, were more common in Asian women than in Caucasian and other women. Our data suggest that histologic types of epithelial ovarian cancer are etiologically distinct. 相似文献
44.
45.
复方葆春袋泡茶质量标准研究 总被引:3,自引:0,他引:3
目的:制订复方葆春袋泡茶质量标准。方法:双波长薄层扫描法测定了五味子乙素的量,对淫羊藿,五味子,女贞子进行了薄层色谱鉴别。结果;加样回收率平均为97.15%(RSD=1.2%,n=5),标准曲线r=0.9991,重复性RSD=1.4%(n=6)精密度RSD=2.3%(n=6),结论,方法稳定,可靠,可作为该制剂的质量控制方法之一。 相似文献
46.
K-ras and p53 mutations in the pathogenesis of classical and goblet cell carcinoids of the appendix. 总被引:8,自引:0,他引:8
BACKGROUND: Mutations in the K-ras oncogene and the p53 tumor suppressor gene are present in approximately 50% of colonic adenocarcinomas. Goblet cell carcinoids (GCCs) are uncommon neoplasms of the appendix that appear to be intermediate between carcinoid tumors and adenocarcinomas, both histologically and biologically. The current study was undertaken to examine the role of p53 and K-ras mutations in the pathogenesis of GCCs and typical carcinoids (TCs) of the appendix. METHODS: Archival materials from 22 GCCs and 18 TCs were analyzed. K-ras mutations in codons 12, 13, and 61 were studied by a polymerase chain reaction (PCR) based designed restriction fragment length polymorphism method using mismatched nested primers. Mutations in exons 5-8 of the p53 tumor suppressor gene were analyzed in 16 GCCs and 18 TCs by PCR and single-strand conformational polymorphism followed by direct sequencing. Immunostains for p53 and chromogranin were performed in all cases. RESULTS: K-ras mutations and nuclear accumulation of p53 by immunohistochemistry were not detected in any of the GCCs or TCs. p53 mutations were found in 4 of 16 GCCs (25%) and 8 of 18 TCs (44%). Immunoreactivity for chromogranin was seen in the vast majority of GCCs and TCs. CONCLUSIONS: p53 mutations appear to play a role in the pathogenesis of some GCCs and in approximately 50% of TCs of the appendix, whereas mutations in the K-ras oncogene do not appear to be important in the development of these tumors. The minimal cytologic atypia, low incidence of metastases, and lack of K-ras mutations in goblet cell appendiceal neoplasms suggest that they are variants of carcinoid tumors. Our findings lend support to the recommendation that the therapeutic guidelines applied to TCs of the appendix should be the same for GCCs. 相似文献
47.
Vestibular hair cell pathology in the Shaker-2 mouse 总被引:2,自引:0,他引:2
The circling-waltzing behaviour of the Shaker-2 mouse is suggested, at least in part, to be of peripheral origin. In this hereditary inner ear disease, degeneration of hair cells type I has been observed showing specific pathologic features: rod-shaped inclusion bodies and sensory hair fusion. Later, the hair cells type I are expelled into the endolymphatic space. A large number of sensory cells type II are morphologically normal. The failure of earlier investigators to demonstrate pathological changes in the sensory epithelia of this animal is likely to be due to the use of light microscopical methods only. 相似文献
48.
0引言食管静脉曲张破裂出血是肝硬变的严重并发症之一.近年研究表明,血清LN水平与食管静脉曲张关系密切.我们分析了108例肝炎肝硬变病例,就LN水平与食管静脉曲张程度的关系做一分析.回对象和方法1.l对象选择肝炎肝硬变连续住院患者108(男gi,女17)例,年龄43.75岁士16.92岁,慢性肝炎患者62(男sl,女11)例,年龄38.20岁士13.20岁,均测定血清1。N水平,并行电子胃镜检查.诊断标准均符合1995-05月北京第五届全国传染病和寄生虫病学术会议修订的病毒性肝炎诊断标准.1.2方法采用放射免疫法测定I。N水平;用电子胃镜确定食… 相似文献
49.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献
50.