ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Malignant melanoma arising in the head and neck mucosa is a rare entity with incidence ranging from 2% to 10%. Because of the lack of data, the biological behaviour of these lesions still remains unpredictable and outcome dismal. We carried out a literature review for cases of mucosal melanoma of the head and neck reported from India and performed a pooled analysis on the available data. A total of 60 cases of head and neck melanomas were reported, of which 46 were in men. Palate and alveolus were the commonest sites. A total of 29 (48.3%) patients had regional node metastasis at presentation while five (12%) had distant metastasis. Three-year overall survival of 27.7% was observed. However, the disease-free survival rates at 3, 5 and 6 years were 39.4%, 39.4% and 13.1%, respectively. Metastasis at presentation and use of adjuvant radiotherapy were found to be the only significant predictors of survival. Malignant mucosal melanoma has aggressive biological behaviour and poor outcome. Radical surgery and adjuvant radiotherapy may provide a better local control and may help in improving survival.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The aim was to estimate the cancer mortality explained by tobacco smoking and alcohol risk drinking. The methods included (1) smoking rates from the largest population survey and alcohol drinking data from the German National Health Survey, and (2) vital statistics from Germany. The tobacco- and alcohol-related data were analysed using formulas for the estimation of attributable fractions. The results show that 19.7% of all malignant neoplasm deaths are explained by tobacco smoking alone, a further 0.2% by alcohol consumption alone and a further 5.6% by tobacco smoking and alcohol drinking. It is concluded that this overlap in the two substance use behaviours has to be taken into account when considering attributable mortality data.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

We investigated "the "chemopreventive potential of lycopene against gastric carcinogenesis induced in male Wistar rats byN-methyl-N′-nitro-N-nitrosoguanidine (MNNG) and saturated sodium chloride (S-NaCl). Administration of lycopene inhibited MNNG+S-NaCl-induced gastric carcinogenesis as revealed by the absence of carcinomas. Lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathioneS-transferase (GST) and glutathione reductase (GR) were used to monitor the chemopreventive potential of lycopene. The extent of lipid peroxidation was significantly lower, whereas GSH, GPx, GST and GR were markedly enhanced in the gastric mucosa of tumour-bearing animals. Our data suggest that lycopene may exert its inhibitory effects by modulating the oxidant and antioxidant status in the gastric mucosa.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

This study assessed the influence of active and passive smoking on the risk of stomach cancer by subsite. Mailed questionnaires were used to obtain information on 1171 newly diagnosed histologically confirmed stomach cancer cases and 2207 population controls between 1994 and 1997 in eight Canadian provinces. Data were collected on socio-economic status, lifestyle and passive smoking status. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived by logistic regression. Compared with those who had never smoked, there was strongly increased risk for ex- and current smokers among subjects with cardial stomach cancer. For men with cardial cancer, the adjusted ORs were 1.9 (95% CI 1.2–3.0) and 2.6 (95% CI 1.6–4.3) for ex-smokers and current smokers, respectively, with a similar pattern among women. Among men, the adjusted ORs were lower for subsites of stomach cancer other than cardia. These findings suggest that active and passive smoking may play an important role in the development of cardial stomach cancer.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

A previous investigation demonstrated the anticarcinogenicity of acetaminophen (APAP) against colon carcinogenesis in rats induced by 3,2′-dimethyl-4-aminobiphenyl (DMAB). DMAB was selected as a structurally related surrogate for heterocyclic amines, formed during cooking of protein, which are believed to be involved in human colon cancer. The objective of the present study was to ascertain whether the early initiating effects of this colon carcinogen are inhibited by APAP. Six groups of male F344 rats were treated over a 6-week period as follows: (1) vehicle (corn oil) for 6 weeks; (2) APAP in the diet at 1000 ppm daily for 6 weeks; (3) 50 mg/kg DMAB by gavage once a week for the last 4 weeks; (4) 5 mg/kg DMAB as for (3); (5) 1000 ppm APAP for 6 weeks and 50 mg/kg DMAB for the last 4 weeks; and (6) 1000 ppm APAP and 5 mg/kg DMAB as for (5). Colonic tissue was within normal limits in the control and APAP groups. In the APAP only group, apical enterocytic hypertrophy and hyperaemia over the entire surface epithelium was present. In the high-dose DMAB group, in the lower third of the crypts, foci of enlarged glands with hypertrophic cells exhibiting karyomegaly and anisokaryosis (FHE) of 3+ degree of severity were evident in 100% of the animals. Also, there were increases in periglandular fibrocytes, matrix and mononuclear cells (PF). In the low-dose DMAB group both FHE and PF changes with the same degree of severity were reduced. In rats given the low dose of DMAB plus APAP, FHE and PF with the same degree of severity (3+) was absent. Both DMAB exposures increased significantly the replicating fraction of colonic enterocytes in an exposure-related fashion and the replicating fractions were significantly reduced by APAP. In32P-postlabelling of colon, liver and urinary bladder DNA, high-dose DMAB produced 2–6 distinct dose-related spots reflecting DNA adducts. These spots were reduced or were no longer detectable in all three tissues when APAP was given 2 weeks before and during DMAB exposure. Using immunohistochemical detection of DMAB adducts in the colon, a dose-related colour intensity was present for both doses of DMAB. APAP reduced this by 94-fold. Thus, APAP produced a marked protective effect in colonic enterocytes against several parameters of neoplastic development by the carcinogen.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Differences regarding signs and symptoms between nodular melanoma (NM) and superficial spreading melanoma (SSM) with a tumour thickness ≤2.00 mm were studied. Reasons for seeking medical attention were also investigated. Semi-structured interviews were conducted with 22 patients with NM diagnosed between 1994 and 1999 and 32 patients with SSM, matched to the NM patients with respect to age at diagnosis, gender and tumour thickness. NM were smaller in diameter, and 5 of 6 patients reporting a diameter <5 mm had NM. NM were more often new lesions than SSM, which more often had developed from pre-existing naevi. In most cases (61%), the melanoma was first detected by the patient and in 17% it was detected by the patient in combination with a family member. The most important reasons to seek medical attention were a change in the lesion or a symptom (65%), followed by encouragement from others to seek medical attention. Twenty-four patients (44%) had no symptoms of melanoma prior to diagnosis. Our results have important implications for prevention. It should be emphasized in public education that melanomas may have a diameter <6 mm and that family members have an important role in detection of melanoma and in motivating medical advice.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Chemoprevention is a rapidly growing area of oncology that is identifying agents with a potentially preventive role in cancer. In this study, it was our goal to compare the chemopreventive effects of vitamin E plus selenium, and melatonin. Forty female mice were divided into four equal groups. The first group served as control. The second group had i.p. injections of 7,12-dimethylbenz[a]anthracene (DMBA) (20 mg/kg body weight) in corn oil for 21 days. The third group had the same procedure of DMBA injections as the second group and received vitamin E+selenium (90 μg+1.8 μg/day), simultaneously. The fourth group had DMBA injections and melatonin (4.2 mg/kg body weight), simultaneously. DMBA alone caused significant inhibition of hepatic glutathione peroxidase (GSHPx), catalase (CAT), and superoxide dismutase (SOD) in the second group. In the third group, vitamin E+selenium restored DMBA-induced GSHPx inhibition significantly whereas CAT and SOD inhibition remained essentially unchanged. In the fourth group, melatonin not only significantly decreased DMBA-induced GSHPx inhibition but also fully reversed CAT and SOD inhibitions caused by DMBA. We speculate that melatonin alone provides better chemoprevention against DMBA-induced oxidative stress than the vitamin E+selenium combination.

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2002

数据来源: OVID