Assessing the potential cost-effectiveness of retesting IHC0, IHC1+, or FISH-negative early stage breast cancer patients for HER2 status
Article first published online: 17 JUN 2013
Copyright © 2013 American Cancer Society
Volume 119, Issue 17, pages 3113–3122, 1 September 2013
How to Cite
Garrison, L. P., Lalla, D., Brammer, M., Babigumira, J. B., Wang, B. and Perez, E. A. (2013), Assessing the potential cost-effectiveness of retesting IHC0, IHC1+, or FISH-negative early stage breast cancer patients for HER2 status. Cancer, 119: 3113–3122. doi: 10.1002/cncr.28196
- Issue published online: 20 AUG 2013
- Article first published online: 17 JUN 2013
- Manuscript Accepted: 29 APR 2013
- Manuscript Revised: 4 APR 2013
- Manuscript Received: 13 FEB 2013
- HER2 testing;
- early breast cancer;
Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) tests are commonly used to assess human epidermal growth factor 2 (HER2) status of tumors in patients with breast cancer. This analysis evaluates the likely cost-effectiveness of expanded retesting to assess HER2 tumor status in women with early stage breast cancer.
We developed a decision-analytic model to estimate the incremental cost-effectiveness ratio (ICER) of expanded reflex testing from a US payer perspective. Expanded reflex testing is defined as retesting tumor specimens from patients whose tumors are IHC0, IHC1+, or FISH-negative on their first test. In the base case, we assumed that 80% of patient tumors are initially IHC-tested and 20% are FISH-tested. Testing outcomes for IHC and FISH with and without retesting were based on published meta-analyses. The cost of tests and treatment and the long-term health outcomes were obtained from the literature.
In the base case, we estimated that 2.27% of women who received expanded reflex testing would be HER2-positive and receive trastuzumab treatment: the projected ICER was $36,721 per life year or $39,745 per quality-adjusted life year (QALY). This varied between $47,100 per QALY and $35,500 per QALY if we assumed that 1%-8% of patients retested were then HER2+, respectively. The results of deterministic and probabilistic sensitivity analysis were robust. This strategy would result in 4700 (2000-17,000) patients being eligible to receive trastuzumab treatment annually.
Retesting patients who are IHC0, IHC1+, or FISH-negative is projected to be a cost-effective clinical strategy. Cancer 2013;119:3113–3122. © 2013 American Cancer Society.