Biomedical subjects

T Therneau

Publications and source records attributed to T Therneau.

5 recordsLinked to original sources

PubMed1991

DNA content flow cytometry as a prognostic factor for node-positive breast cancer. The role of multiparameter ploidy analysis and specimen sonication.

The DNA content was analyzed in paraffin-embedded material from 167 patients with node-positive breast cancer to learn whether specimen sonication and multiparameter ploidy analysis (MPPA) (using DNA content and light scatter) could improve the strength of ploidy as a prognostic variable. Sonicated specimens were found to have fewer aggregates, a lower percentage of cells in S-phase (%S) and G2M phase than the corresponding nonsonicated specimens. The results using MPPA predicted the prognosis better because they allowed detection of small aneuploid peaks in histograms classified as diploid or tetraploid using DNA content alone. Ploidy was a significant univariate factor, and patients with tetraploid tumors had the best survival. In the multivariate analysis, if other routine factors were examined preferentially, ploidy and %S did not provide additional prognostic information for survival. This study of paraffin-embedded breast cancers suggested that sonication and MPPA may improve the ploidy analysis in certain cases and that tetraploidy may be a favorable ploidy pattern in this group.

Breast Neoplasms↗

PubMed1990

A phase II randomized trial of megestrol acetate or dexamethasone in the treatment of hormonally refractory advanced carcinoma of the prostate.

The results of a randomized, multicenter, cooperative group trial evaluating hormonal therapy with either megestrol acetate or dexamethasone in advanced, hormonally refractory prostate cancer are reported. Three of 29 patients (approximately 10%) on the megestrol acetate arm experienced an objective response lasting 41, 84, and 202 days, respectively, whereas two of 29 patients (approximately 7%) on the dexamethasone arm achieved an objective response lasting 359 and 512 days, respectively. Twenty of 29 patients (approximately 69%) on the megestrol acetate arm had stable disease lasting for a median duration of 117 days, whereas 21 of 29 patients (72%) on the dexamethasone arm had stable disease for a median duration of 86 days. Median survival of all patients was 9 months from initiation of treatment. The median survival of all patients on the megestrol acetate arm was 268 days compared to 246 days for patients on the dexamethasone arm (P = 0.2). Neither dexamethasone nor megestrol acetate would seem to be of substantive value in altering the progression of advanced, hormonally refractory prostate cancer.

Aged↗

PubMed1989

Pattern of failure after radical retropubic prostatectomy for clinically and pathologically localized adenocarcinoma of the prostate: influence of tumor deoxyribonucleic acid ploidy.

From 1966 to 1980, 315 patients underwent bilateral pelvic lymphadenectomy and radical retropubic prostatectomy without adjuvant treatment for clinically and pathologically localized adenocarcinoma of the prostate. Followup was 5 to 21 years, with a median of 8 years. The disease was pathological stage A in 24 patients (8%) and pathological stage B in 291 (92%). A total of 45 patients (14.2%) experienced progression. Over-all, 28 patients (8.9%) suffered local recurrence at a mean of 6.6 years postoperatively (median 5.5 years). Local recurrence was noted as late as 15 years postoperatively. Over-all, systemic progression was observed in 25 patients (8%) after a mean of 4.7 years (median 6 years). Eight patients (2.5%) experienced local and systemic failure. The projected local and systemic failure rates at 15 years were 22% and 15%, respectively. Disease-specific survival at 15 years was 93%, since only 11 patients (3.4%) died of prostate cancer. In an age-matched case control analysis, after all prognostic variables were analyzed (Mayo grade, Gleason score, capsule involvement, number of foci, volume of tumor and deoxyribonucleic acid tumor ploidy), progression was related to nondiploid deoxyribonucleic acid tumor ploidy (p less than 0.0004) as determined by flow cytometry in 63% of the patients who evidenced progression versus 8% of the nonrecurrent group.

Adenocarcinoma↗

PubMed1987

The mortality risk associated with digitalis treatment after myocardial infarction.

We examined the effects of digitalis therapy on postinfarction mortality throughout a 24-month to 48-month follow-up in 867 patients who survived an acute myocardial infarction. During follow-up, 145 patients died (16.7% mortality). At the time of hospital discharge, 31% of the patients were taking digitalis. The digitalis-treated patients were older, had more medical-cardiac risk factors, and had a higher mortality rate throughout the follow-up than the nondigitalis-treated patients. Statistical techniques were used to adjust for clinical imbalances between the digitalis-treated patients and nondigitalis-treated patients. The survival analysis (n = 728 patients) utilized the Cox regression model, and the digitalis-associated mortality risk was identified only after all significant covariates were allowed, so that mortality could be predicted as accurately as possible. Digitalis therapy was associated with a significantly increased postinfarction mortality risk after adjustment for the predictor covariates (relative risk 2.3, 95% confidence interval 1.4-3.7, p less than 0.001). The findings from this large multicenter study suggest that it would be prudent to exercise caution in the use of digitalis in postinfarction patients.

Aged↗

PubMed1987

A two-stage design for randomized trials with binary outcomes.

A two-stage rule for a randomized clinical trial with a dichotomous outcome is presented. It is based on a rule discussed by Ellenberg and Eisenberger (Cancer Treat Rep 69:1147-1154, 1985). The rule is shown to lead to a reduction in expected sample size if the test treatment is ineffective, with almost no loss in power. All the mathematical formulas required to design such a rule are given, as well as some time-saving approximations. The accuracy of the approximations is shown.

Clinical Trials as Topic↗