Pyrhonen 1997.
| Study characteristics | ||
| Methods | Design: A randomised, multicentre, double‐blind, phase III trial Centres: 26 centres in 6 countries (Finland, Sweden, Norway, Poland, Hungary and the Czech Republic) Accrual: From June 1986 to May 1992 Randomisation: The patients were stratified by whether or not they had measurable or only evaluable disease and were randomly assigned to treatment with TOR or TAM. Randomisation was performed centrally, using computer generated lists that were prepared separately for both stratification groups and for each participating centre. Baseline comparability: Patient characteristics are evenly balanced between the two arms except for the levels of ER: in the TAM group a larger proportion of patients had high ER‐levels (mean ER‐concentrations 119 and 171 fmol mg‐1 cytosol protein for TOR and TAM patients, respectively) |
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| Participants | 415 post‐menopausal patients with histologically or cytologically verified inoperable primary, metastatic or recurrent breast cancer that was ER‐positive or ER‐unknown Age (mean and range): Arm A, 65.5 (33.6 to 87.6); arm B, 65.9 (44.8 to 90.2) |
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| Interventions | Arm A (n = 214): TOR 60 mg (TOR) Arm B (n = 201): TAM 40 mg (TAM) |
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| Outcomes | Response Time to progression Time to treatment failure Duration of response Overall survival Toxicity |
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| Notes | Median follow‐up time was 25.2 months. 379 (91.3%) patients were eligible. The performance status and body weights of the patients were similar in the treatment groups throughout the study ITT analysis was used. The response rates were calculated for all randomised patients as well as for all eligible and all evaluable patients separately. The results appeared to be similar 176 (82.2%) patients in TOR and 147 (73.1%) patients in TAM progressed at the time of data cut‐off. HR of time to progression (TOR vs TAM) was 1.25 (95% CI: 1.00 to 1.56) Median time to treatment failure was 6.3 months in TOR and 8.5 months in TAM. HR (TOR vs TAM) was 1.12 (95% CI: 0.92 to 1.38) 123 (57.5%) in TOR and 115 (57.2%) in TAM died at the time of data cut‐off. Median overall survival was 33.0 (28.5 to 37.0) months in TOR and 38.7 (31.8 to 41.9) months in TAM. The difference was not statistically significant (P = 0.645) (HR not reported) |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | The random sequence was generated by computer |
| Allocation concealment (selection bias) | Unclear risk | No information was provided |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | This is a double‐blind trial |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | This is a double‐blind trial |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Data for every prespecified outcome were completely reported |
| Selective reporting (reporting bias) | Low risk | Data for every prespecified outcome were completely reported |
| Other bias | High risk | The baseline ER‐levels were significantly different between the two groups |