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11.
Colorectal cancer is the commonest malignancy in patients aged 75 years or older. The incidence is likely to rise further over the next two decades as the population ages and survival increases. Robust data on the adherence to guidelines for the elderly and the uptake of treatment in the elderly are limited—particularly with regard to rectal cancer. However, the evidence available suggests that clinical attitudes observed regarding age and cancer treatment are consistent. Older people with colorectal cancer tend to be offered either less intensive treatment or no treatment at all. Population data confirm that treatment rates for surgery, chemotherapy and radiotherapy in patients with colorectal cancer all decline for those over 70 years old, and continue to decline exponentially with increasing age. So should new, more tolerable strategies which may avoid radical surgery be more widely available (short-course preoperative radiotherapy, chemoradiotherapy, transanal excision microsurgery, brachytherapy, contact therapy)? It is not clear if oncologists are always making the most appropriate management decisions. So how do oncologists and surgeons balance chronological age, comorbidity, social isolation and other influences in their clinical decision-making? We need to recognise that this is a difficult issue and will be an increasing issue for multidisciplinary teams.  相似文献   
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Summary Endothelial dysfunction is considered to be the first step in atherogenesis as well as a predictor of adverse cardiovascular events in patients with coronary artery disease (CAD), while endothelial function improvement is associated with improved clinical outcome. Nebivolol is a beta1-adrenoreceptor antagonist with an independent beneficial action on endothelial function, increasing nitric oxide bioavailability. The aim of the present study was to examine the effects of nebivolol on endothelial function in the brachial artery in patients with CAD compared with another selective beta1 adrenergic receptor antagonist, atenolol. Thirty-five patients with stable CAD were randomized to receive either 5 mg nebivolol (n = 17) or 50 mg atenolol (n = 18) daily for 4 weeks. Each patient underwent measurement of endothelial function by means of flow-mediated dilatation (FMD) of the brachial artery before and after 4 weeks of treatment. All vasoactive drugs and cardiovascular risk factors were comparable in the two groups. No significant differences were observed between the two groups at baseline in FMD. In the atenolol group FMD remained unchanged at the end of the 4-week treatment, but in patients treated with nebivolol FMD showed a significant increase by the end of the treatment period (3.9 ± 2.7% vs. 5.6 ± 2.9%, p = 0.047) leading to a significantly higher value compared to patients treated with atenolol (5.6 ± 2.9% vs. 3.4 ± 3.2%, p = 0.041). Beta1 blockade by nebivolol but not atenolol improves endothelial dysfunction in patients with CAD, an effect that might further reduce the risk for cardiovascular events in patients with CAD.  相似文献   
14.
Short-term cigarette smoking is associated with persistent endothelial dysfunction. Data on the reversibility of this effect with per os antioxidants after short-term smoking are lacking. This study examines the effect of orally administered ascorbic acid on cigarette smoking-induced endothelial dysfunction. In the present double-blind, randomized, crossover study, 19 healthy subjects (28.7 +/- 6.8 years, mean +/- SD) were examined by high-resolution ultrasonography of the brachial artery before and 0, 30, 60, 90, and 120 minutes after smoking a cigarette. Flow-mediated dilatation (FMD) was used as a method to examine endothelial function. Measurements were performed on two different days, 2 hours after oral administration of 2 g of ascorbic acid or placebo. FMD was similar for each subject between the two visits at baseline. FMD was significantly decreased after smoking with both placebo and ascorbic acid. However, there was a significant beneficial effect of ascorbic acid on the FMD change over time after smoking. After smoking, the FMD dropped to less than half of the baseline value. Thereafter in the placebo group, FMD increased to 70% of baseline value in 90 minutes, but in the ascorbic acid group the FMD increased to 70% of baseline value in 46 minutes. Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking by shortening its duration.  相似文献   
15.
PURPOSE: To analyze the presentation features and outcome for patients with immunocytoma (IMC) managed at St Bartholomew's Hospital (SBH), London, United Kingdom, between 1972 and 1996. Outcome was compared with that of patients with small lymphocytic lymphoma (SLL)/B-cell chronic lymphocytic leukemia (B-CLL) treated at SBH during the same period. PATIENTS AND METHODS: One hundred twenty-six patients with newly diagnosed IMC were identified. Patients were subclassified (using the Kiel classification) as having lymphoplasmacytoid (n =92), lymphoplasmacytic (n = 24), polymorphous (n = 9), or undetermined (n = 1) IMC. Six patients (5%) had stage I to IIE disease; the rest had advanced disease. Treatment was given according to disease stage. Seven patients were managed expectantly. RESULTS: Eighty-two (69%) of 119 patients responded to treatment, but complete remission was seen in only 15 (13%) of 119. Treatment failed in 29 (24%) of 119 patients. There were three treatment-related deaths; five patients were not assessable for response. When survival of patients with IMC was compared with that of patients with B-CLL/SLL, a significant difference was found (P <. 01); this difference was maintained when only patients in whom the diagnosis was based on lymph node biopsy were considered (P =.01). A comparison of the three IMC subgroups showed that there was a trend (P =.06) toward a difference between B-CLL/SLL and the lymphoplasmacytoid subtype. CONCLUSION: Patients diagnosed with IMC are generally older and present with advanced disease. Conventional therapies usually result in incomplete responses of short duration. Overall, these results support the proposed World Health Organization reclassification of IMC to include lymphoplasmacytoid lymphoma (Kiel classification) as a variant of B-CLL/SLL.  相似文献   
16.
BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) represents a seldom malignancy in most developed countries. Nevertheless, NPC receives an endemic form in concrete racial entities. The aims of this study were to detect the presence of Epstein-Barr virus DNA (EBV-DNA) in peripheral blood of NPC patients, to molecularly define human leukocyte antigens (HLA) DRB1*, DQA1* and DQB1* allele frequencies, and, finally, to determine whether the genetic predisposition of an individual to NPC depends on the liability to EBV infection. PATIENTS AND METHODS: A total of 101 patients of Hellenic origin and nationality, with histologically proven NPC, participated in this study. EBV-DNA detection was also applied in 66 patients with EBV-related malignancies (Hodgkin's [HL] and non-Hodgkin's lymphoma [NHL]) and infectious mononucleosis (IM), as well as in 80 healthy EBV-seropositive controls. RESULTS: 81% of the NPC patients, 77.8% with HL, 72.2% with NHL, and 66.7% with IM were EBV-DNA positive, whereas the EBV genome was detected only in 15% of the healthy controls. These differences were statistically significant in all cases. Analysis of HLA class II antigens showed decreased frequency of the DRB1*07 (p = 0.003), DQA1*0103 (p = 0.002), and DQA1*0201 (p = 0.003) alleles among NPC patients. A significant association between the HLA-DR/DQ alleles and the presence of EBV-DNA in peripheral whole blood was not established. CONCLUSION: Circulating EBV-DNA and specific HLA class II alleles may predispose to or protect from NPC. However, the results of this study suggest that the genetic predisposition of an individual to NPC is independent of the liability to EBV infection.  相似文献   
17.
Estrogens and androgens may play an important role in vascular health in both sexes. The aim of this study was to examine the relation of endogenous sex hormone levels with early markers of atherosclerosis in a cohort of apparently healthy males. 124 males (age 46.25 ± 9.56) attending a preventive medicine program were examined for unrecognised features of the metabolic syndrome. Flow-mediated dilatation (FMD) and intima-media thickness (IMT) of the common carotid artery were evaluated. Obesity parameters were recorded; estradiol, testosterone, SHBG, free testosterone, insulin, as well as glucose and lipid levels were measured. FMD was positively correlated with estradiol (r = 0.201, P = 0.041) and negatively with total cholesterol (r = -0.205, P = 0.022), low density lipoproteins (r = -0.232, P = 0.009), and triglyceride levels (r = -0.179, P = 0.046). In multivariate analysis, the association of FMD with estrogen was independent of BMI and lipid levels. No significant association between FMD and testosterone levels was found. Subjects with an increased mean IMT (> 0.73 mm, i.e., > 3rd tertile) had lower levels of free (P = 0.021) and bioavailable (P = 0.016) testosterone. In multivariate logistic regression analysis, this association was no longer significant when age or cholesterol levels were considered. Endogenous estrogen levels are associated with FMD, independently of age and lipid levels, showing a protective effect in middle-age male subjects. Circulating androgens are associated, although not independently, with structural changes such as the IMT of carotid artery; this effect is possibly influenced by lipid levels and age.  相似文献   
18.
We present a rare case of multiple metastases of a prostatic adenocarcinoma to the urethra. Radical prostatectomy had been performed 13 years before, and during this time he had been frequently treated with transurethral resections of the bladder neck for obstructive urinary symptoms.  相似文献   
19.
Resting ankle-brachial pressure index (ABI) is a noninvasive method to assess the patency of the lower extremity arterial system. This study aimed to examine the relation between ABI and the extent of coronary atherosclerosis, the extracoronary atherosclerosis lesions, and the prognosis of patients referred for elective coronary angiography. One hundred sixty-five consecutive patients underwent coronary angiography, ultrasound imaging for intima-media thickness measurement of carotid and femoral arteries and ABI evaluation; subjects were followed up for 14.5 +/- 2.4 months. With regard to vascular risk factors, only smoking (p = 0.025) and diabetes (p = 0.01) were related to ABI in the multiple regression analysis. ABI was independently and inversely related to carotid bifurcation (p = 0.0002) and common femoral artery intima-media thickness (p = 0.018). ABI was related to the extent of coronary artery disease as measured by number of coronary arteries diseased (analysis of variance, p = 0.04) and Gensini angiographic score (p = 0.01). In the follow-up study ABI < 0.90 was a univariate predictor of cardiovascular events (cardiac death, nonfatal myocardial infarction, unstable angina) and revascularization procedures. The estimated cumulative rate free of cardiovascular events was 90% for ABI > 0.90 and 73% for ABI < 0.90 (p = 0.02). In logistic regression analysis, ABI < 0.90 was an independent predictor for cardiovascular events after adjustment for age, low-density lipoprotein cholesterol, carotid and femoral intima-media thickness, and Gensini score. Further adjustment for the confounding effect of insulin weakened the relation between ABI and cardiovascular events (p = 0.1). In conclusion, ABI is a simple index related to the extent of atherosclerosis in coronary and noncoronary arterial beds, reflecting generalized atherosclerosis. ABI could be useful in assessing the risk for cardiovascular events in patients with coronary artery disease.  相似文献   
20.
This paper presents the largest study in Cyprus evaluating the frequency and distribution of BRCA1/2 mutations in a high risk patient cohort. Deleterious mutations in the BRCA1/2 genes were identified in 68 of the 527 patients tested (13%). It is of interest that a quarter of those tested positive, did not have an extensive family history of breast/ovarian cancer but were diagnosed with early onset breast cancer, ovarian cancer under the age of 60 or triple negative breast cancer. The spectrum of mutations identified in our patient cohort is different compared to other Mediterranean countries. Furthermore, several of the mutations detected are novel and have not been identified in other ethnic populations. This highlights the importance of operating a national reference center for cancer genetic diagnosis which offers services tailored to the needs of the Cypriot population.  相似文献   
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