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Journal of Clinical Oncology, 2004 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 22, No 14S (July 15 Supplement), 2004: 522
© 2004 American Society of Clinical Oncology
An independent population-based validation of the adjuvant decision-aid for stage I-II breast cancer
I. A. Olivotto,
C. Bajdik,
P. M. Ravdin,
B. Norris,
A. J. Coldman,
C. Speers,
S. Chia and
K. Gelmon
BC Cancer Agency, Victoria, Vancouver and Surrey, BC, Canada; University of Texas, San Antonio, TX
522
Background: ADJUVANT! (ADJ! [JCO 2001;19:98091]) is a computer model which predicts 10-yr overall (OS), breast cancer-specific (BCSS) and event-free (EFS) survival with and without systemic therapy using recognised prognostic factors. Oncologists use it to provide information to patients about prognosis and treatment choice. ADJ! has not been independently validated despite widespread use. Methods: Demographic, pathology, staging and treatment data on 4,083 women with pT12, pN01 breast cancer referred to the BC Cancer Agency during 19891993 were entered into ADJ! 10-yr predicted (pred) OS, BCSS and EFS were calculated for each patient. Breast Cancer Outcomes Unit observed (obs) status at 10 years (disease event yes/no; alive; dead of disease; dead of other cause) was independently determined for each patient. ADJ! pred and BCOU obs rates were compared. Study subject pathologic characteristics were: 66% pT1, 34% pN1, 58% ER+, 37% grade 3 and 36% with lymphovascular invasion (LVI+). Three percent were age 2035 years, 9.7% were age >75 years. Systemic therapy was: none=45%, tamoxifen (TAM) alone=30%, chemo (CT) alone=16% and CT+TAM=9%. Results: Across all 4083 patients, 10-yr pred and obs outcomes were within +/ 1% for OS (pred=71.7%, obs=72%), BCSS (pred=83.2%, obs=82.5%) and EFS (pred=71%, obs=70.1%). ADJ! overestimated EFS in women 35 yrs (pred=67.9%, obs=54.3%; p<0.002) and with LVI+ disease (pred=66.5%, obs=62.3%, p<0.001). ADJ! predicted BCSS and EFS rates within +/ 2% for patients not receiving systemic therapy or receiving TAM alone. ADJ! overestimated EFS with CT (pred=65%, obs=61.3%; p=0.056) and especially with combined CT+TAM (pred=68.1%, obs=61.7%; p=0.012). Conclusions: Overall, ADJ! performed reliably. Two factors to be added to future revisions of ADJ! were identified: age 35 and LVI+. ADJ! was overly optimistic about the outcomes of combined CT+TAM (by about 5% absolute) for OS, BCSS and EFS. Validation in large population-based databases like the BCOU, supports the translation of prediction models into practice. Supported in part by the Canadian Breast Cancer Research Alliance.
Author Disclosure
| Employment or Leadership |
Consultant or Advisory |
Stock Ownership |
Honoraria |
Research Funding |
Expert Testimony |
Other Remuneration |
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| Adjuvant, Inc. |
Adjuvant, Inc. |
Adjuvant, Inc. |
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Abstract presentation from the 2004 ASCO Annual Meeting
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