Citation
Gosselin C. Utilisation du test Oncotype DXMD aux fins de décision thérapeutique dans le contexte du traitement du cancer du sein infiltrant
. [Use of the Oncotype DX® test for therapeutic decision-making in the context of treating invasive breast cancer] Quebec: Institut national d'excellence en sante et en services sociaux (INESSS). 2016
Authors' conclusions
The ODX test is a prognostic and predictive tool of the benefit of adding adjuvant CT to treatment in patients with early-stage, HER2-/ER+ breast cancer treated with HT. The level of evidence for the test's predictive value is, however, low because of the methodological limitations of the available studies. Nonetheless, it seems that this tool facilitates decision-making regarding the need to recommend adjuvant CT in node-negative patients by modifying the treatment recommendation in about 30 % of the cases and reducing by about 11 % the recommendation to use CT. However, a better histopathological evaluation of the tumour subtype could diminish this effect of the ODX test. Furthermore, there is presently no evidence indicating that treatment decision changes (withdrawing or adding CT) based on the result of the ODX test improves patient's long-term outcomes, in particular, recurrence-free survival.
Since there is no alternative that is fully equivalent to the ODX test, INESSS considers that this test has value-added in certain circumstances where clinical decision-making is difficult. However, the result of an ODX test should always be considered together with all the other standard CPPs and never replace the clinician's judgment, especially because of the weakness of the evidence for its predictive value. Consequently, it is important that the test be ordered only after the appropriateness and feasibility of CT have been thought through by a clinician who has a good understanding of the molecular subtypes of breast cancer. Furthermore, to promote the judicious use of the test, the patient should participate in this deliberation that leads to the test being ordered.
Although INESSS considers that the ODX test has a role to play as a clinical decision-making tool in certain breast cancer cases, it feels that its use (ordering and the approval process) needs to be monitored, especially because of its high cost and because it's value-added is probably limited in certain clinical circumstances. Consequently, INESSS proposes a standardized ODX test requisition form, to which the anatomical pathology report should be attached for perusal. The data gathered on the characteristics of all the patients in whom the test is ordered and the results of these tests could then be analyzed, after which a review of the eligibility criteria or an optimal usage guide could be proposed, if necessary.
Address for correspondence
Institut national d'excellence en santé et en services sociaux (INESSS), 1195 avenue Lavigerie, bureau 60 Québec (Québec) Canada, G1V 4N3
Email: inesss@inesss.qc.ca