Showing papers by "John F. Forbes published in 1997"
Journal Article•
TL;DR: Current trends are largely due to earlier diagnosis, mammographic screening in developed countries, a decrease in deaths in both the United States and the United Kingdom, and an increasing proportion of deaths in developing countries.
111 citations
TL;DR: The efficacy of tamoxifen appears to be similar to that of ovarian ablation by surgery or irradiation as first-line therapy for premenopausal, ER positive metastatic breast cancer, and is unlikely to be substantially inferior.
Abstract: We performed a meta-analysis of randomized trials comparing tamoxifen to ovarian ablation carried out either by surgery or irradiation as first-line hormonal therapy for pre-menopausal women with metastatic breast cancer. Patients in all trials included were required to have measurable disease and to be currently menstruating or within 1 year of cessation of menses, and to have estrogen receptor (ER) positive or unknown disease (ER negative women were admitted to one of the studies). Individual patient data were obtained from the four studies identified and the results updated to June 1992. A total of 220 eligible patients were enrolled in the four trials. There was no difference in overall response rate between tamoxifen and oophorectomy across the four trials (p = 0.94, Mantel-Haenszel test). The odds reduction for progression was 14% ± 12% and for mortality 6% ± 13% in favour of tamoxifen, results which were not statistically significant (p = 0.32 and 0.72, respectively). Although the design of all four studies included a cross-over to the other therapy, only 54/111 patients receiving ovarian ablation and 34/109 patients receiving tamoxifen as primary therapy actually crossed over to the other arm at the time of disease progression. Response to initial treatment with tamoxifen was predictive of subsequent response to ovarian ablation (p < 0.05), and response to initial therapy with ovarian ablation was predictive of subsequent response to tamoxifen (p < 0.05). Support curves based on log-likelihood ratios revealed that this meta-analysis provides moderate evidence rejecting a 14% advantage for ovarian ablation compared to tamoxifen in terms of odds of disease progression. A 25% advantage for ovarian ablation with respect to odds of death is also rejected with moderate evidence. We conclude that the efficacy of tamoxifen appears to be similar to that of ovarian ablation by surgery or irradiation as first-line therapy for premenopausal, ER positive metastatic breast cancer, and is unlikely to be substantially inferior.
70 citations
Journal Article•
TL;DR: Tamoxifen has a particularly valuable role in developing countries in which the incidence of breast cancer is increasing as the average age of the population increases and in which control is substantially more difficult with mass mammography screening.
63 citations
TL;DR: Surgical procedures which are more extensive than a fine needle aspiration biopsy might be associated with worse prognosis if conducted during the follicular phase of the menstrual cycle, as seen predominantly for high risk breast cancer with low levels or no estrogen receptors in the primary tumor.
40 citations
TL;DR: In this article, the authors evaluated whether adding MPA to tamoxifen (TAM) is superior to the substitution of MPA for TAM among women with advanced breast cancer and disease progressing on TAM.
Abstract: PURPOSETo determine whether a strategy of adding medroxyprogesterone acetate (MPA) to tamoxifen (TAM) is superior to the substitution of MPA for TAM among women with advanced breast cancer and disease progressing on TAM. To assess the patterns or response and subsequent progression in sites and tissues according to prior involvement and treatment.PATIENTS AND METHODSTwo-hundred-fifteen postmenopausal women with advanced breast cancer progressing on TAM after receiving TAM for at least six months were randomized: 109 to add MPA 500 mg/day orally (TAM + MPA), and 106 to stop TAM and to substitute MPA.RESULTSThere were no significant differences between the groups with respect to complete plus partial response rates: TAM + MPA 10%, MPA 9%, median time to progression TAM + MPA 3.0 months, MPA 4.5 months, or median overall survival, TAM + MPA 17.2 months, MPA 18.4 months. In a multivariate model, prognostic factors significant for a shorter time to disease progression were worse for performance status, involve...
31 citations
04 Jun 1997
TL;DR: It is shown that the blender control performance can be increased very significantly by eliminating or reducing plant/model mismatch and a new control approach that optimizes over the entire blend, rather than at a point in time is presented.
Abstract: Real-time optimization based control systems are used for blending operations in many industries. Typically, in blending of automotive gasoline, these systems use linear programming with bias update of blending models. This paper considers the performance of such systems in terms of profit level and shows that the blender control performance can be increased very significantly by eliminating or reducing plant/model mismatch. Further, a new control approach that optimizes over the entire blend, rather than at a point in time, is presented and the benefits of adopting this new approach are illustrated. The paper concludes with a brief discussion of observability issues which must be considered to ensure the success of the proposed control scheme.
7 citations
04 Jun 1997
TL;DR: In this paper, the authors present a tractable method by which the behavior of an advanced CD control design can be incorporated into a finite impulse response filter, and the filter weights are determined using semidefinite programming.
Abstract: Due to the limited programming capabilities of some existing cross directional (CD) control platforms, direct implementation of advanced CD control methods is often not possible. This paper presents a tractable method by which the behaviour of an advanced CD control design can be incorporated into a finite impulse response filter. The filter weights are determined using semidefinite programming. Measures of the performance degradation due to the filter approximation are investigated, and the proposed methods are illustrated with a case study.
2 citations