3441. Breast cancer and hormonal contraceptives: collaborative reanalysis of individual data on 53 297 women with breast cancer and 100 239 women without breast cancer from 54 epidemiological studies.
BACKGROUND The Collaborative Group on Hormonal Factors in Breast Cancer has brought together and reanalysed the worldwide epidemiological evidence on the relation between breast cancer risk and use of hormonal contraceptives. METHODS Individual data on 53 297 women with breast cancer and 100 239 women without breast cancer from 54 studies conducted in 25 countries were collected, checked, and analysed centrally. Estimates of the relative risk for breast cancer were obtained by a modification of the Mantel-Haenszel method. All analyses were stratified by study, age at diagnosis, parity, and, where appropriate, the age a woman was when her first child was born, and the age she was when her risk of conception ceased. FINDINGS The results provide strong evidence for two main conclusions. First, while women are taking combined oral contraceptives and in the 10 years after stopping there is a small increase in the relative risk of having breast cancer diagnosed (relative risk [95 percent CI] in current users 1.24 [1.15-1.33], 2p<0.00001; 1-4 years after stopping 1.16 [1.08-1.23], 2p=0.00001; 5-9 years after stopping 1.07 [1.02-1.13], 2p=0.009). Second, there is no significant excess risk of having breast cancer diagnosed 10 or more years after stopping use (relative risk 1.01 [0.96-1.05], NS). The cancers diagnosed in women who had used combined oral contraceptives were less advanced clinically than those diagnosed in women who had never used these contraceptives for ever-users compared with never-users, the relative risk for tumours that had spread beyond the breast compared with localised tumours was 0.88 (0.81-0.95; 2p=0.002). There was no pronounced variation in the results for recency of use between women with different background risks of breast cancer, including women from different countries and ethnic groups, women with different reproductive histories, and those with or without a family history of breast cancer. The studies included in this collaboration represent about 90 percent of the epidemiological information on the topic, and what is known about the other studies suggests that their omission has not materially affected the main conclusions. Other features of hormonal contraceptive use such as duration of use, age at first use, and the dose and type of hormone within the contraceptives had little additional effect on breast cancer risk, once recency of use had been taken into account. Women who began use before age 20 had higher relative risks of having breast cancer diagnosed while they were using combined oral contraceptives and in the 5 years after stopping than women who began use at older ages, but the higher relative risks apply at ages when breast cancer is rare and, for a given duration of use, earlier use does not result in more cancers being diagnosed than use beginning at older ages. Because breast cancer incidence rises steeply with age, the estimated excess number of cancers diagnosed in the period between starting use and 10 years after stopping increases with age at last use: for example, among 10 000 women from Europe or North America who used oral contraceptives from age 16 to 19, from age 20 to 24, and from age 25 to 29, respectively, the estimated excess number of cancers diagnosed up to 10 years after stopping use is 0.5 (95 percent CI 0.3-0.7), 1.5 (0.7-2.3), and 4.7 (2.7-6.7). Up to 20 years after cessation of use the difference between ever-users and never-users is not so much in the total number of cancers diagnosed, but in their clinical presentation, with the breast cancers diagnosed in ever-users being less advanced clinically than those diagnosed in never-users. The relation observed between breast cancer risk and hormone exposure is unusual, and it is not possible to infer from these data whether it is due to an earlier diagnosis of breast cancer in ever-users, the biological effects of hormonal contraceptives, or a combination of reasons...
3442. Abortion and fertility regulation.
To achieve their desired fertility, women use a combination of contraception and abortion, and some societies also place constraints on marriage and sexual activity. The degree to which these means are adopted varies considerably, but for the foreseeable future abortion will remain an important element of fertility regulation. Globally, complications of unsafe abortion affect hundreds of thousands of women each year, and account for as many as 100,000 deaths annually (about two in ten maternal deaths), mainly in poor countries, where abortion typically remains illegal. Access to safe abortion is both essential and technically feasible and should be provided in combination with good quality family planning services.
3443. Syringomyelia as a cause of body hypertrophy.
Among 26 patients with communicating syringomyelia who came to our out-patient clinic from April, 1989, to March, 1995, three (11.5%) had hypertrophy in limbs, hands, or feet. One had crossed hypertrophy. We considered the possibility that syringomyelia caused body hypertrophy.
3445. Systemic sclerosis: current pathogenetic concepts and future prospects for targeted therapy.
来源: Lancet. 1996年347卷9013期1453-8页
Although there is no cure for systemic sclerosis, the disease is certainly treatable. And the more that is understood of its pathogenesis, the better the prospects for treatment. Excessive collagen deposition in the skin and viscera is responsible for the morbidity and mortality. The immune system plays a critical role in setting up the fibrotic process, but impaired regulation of collagen gene expression probably underlies the persistence of fibrosis. The development of effective antifibrotic drugs, in particular agents that inhibit transcription factors involved in the activation of type I collagen genes, is likely to be the way forward for treatment of the later stages of diffuse systemic sclerosis, with immunomodulatory therapy for the earlier stages.
3446. The war on cancer.
25 years ago, then President Nixon "declared" War on Cancer. In this personal commentary, the war is reviewed. There have been obvious triumphs, for instance in cure of acute lymphocytic leukaemia and other childhood cancers, Hodgkin's disease, and testicular cancer. However, substantial advances in molecular oncology have yet to impinge on mortality statistics. Too many adults still die from common epithelial cancers. Failure to appreciate that local invasion and distant metastasis rather then cell proliferation itself are lethal, obsession with cure of advanced disease rather than prevention of early disease, and neglect of the need to arrest preneoplastic lesions may all have served to make victory elusive.
3449. Adjuvant chemotherapy plus tamoxifen compared with tamoxifen alone for postmenopausal breast cancer: meta-analysis of quality-adjusted survival.
作者: R D Gelber.;B F Cole.;A Goldhirsch.;C Rose.;B Fisher.;C K Osborne.;F Boccardo.;R Gray.;N H Gordon.;N O Bengtsson.;P Sevelda.
来源: Lancet. 1996年347卷9008期1066-71页
Adjuvant tamoxifen for early breast cancer provides an improvement in relapse-free (RFS) and overall survival (OS), especially for older women. We carried out a meta-analysis to find out whether the benefit of adding chemotherapy to tamoxifen outweighs its costs in terms of toxic effects for postmenopausal patients.
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