Arising from: Abdullah-Sayani A et al. (2006) Nat Clin Pract Oncol 3: 501–516

In reply to the comments by Dr. Mangesh Thorat, we would like to repeat that we do not have conflcts of interest that need reporting. We conduct research in the area of the content of our review article, but this is of course often the case for authors of a review.

Marc van de Vijver has been involved in the research leading to the identification of the 70-gene prognosis profile, which is now developed as a commercial test by Agedia (MammaPrint® test), a company started out of the Netherlands Cancer Institute. However, none of the authors, including Marc van de Vijver, is involved with Agendia and the commercialization of this 70-gene test.

Also, we have not done a “frontal attack” on the Oncotype Dx® assay; our main critical remark is that there are also studies that fail to confirm the strong prognostic value of that test.

In our review article we have expressed concern that diagnostic tests based on gene expression profiles will be used before they have been properly validated; this concern certainly also includes the MammaPrint® test provided by Agendia, and we would like to reiterate that also this test is not sufficiently validated for clinical use outside clinical trials.