BRAF testing for adjuvant therapy

[Anonymous]

In follow up to the question about use of dabrafenib and trametinib in the adjuvant setting. I’m wondering if you have discussed at your sites the necessity for BRAF testing and that it needs to be done with a “FDA” approved test, which requires not an insignificant amount of tissue, which with primary melanomas may be a major issue, after diagnosis?

Thanks!
Lisa

[Anonymous]

Excellent point, Lisa. We have been trying to sort out how best to accomplish this at our institution. Prior to the adjuvant approval, we had obtained BRAF testing on patients with a high risk of recurrence (i.e. Stage IIC/IIIB/IIIC). Our practice will now be changing to include any Stage III patient. As previously noted, I/O therapy would be preferred, but targeted therapy is an alternative to observation for those with autoimmune conditions. The need for an FDA approved test complicates the situation as our in house test has a fast turn around time, but will not be enough to justify starting adjuvant therapy. So this is a work in progress for us! If anyone has a good system, please pass along!

Virginia

[Samantha Guild]

Tissue availability is a large barrier for BRAF testing especially in patients with microscopic foci in a single lymph node. Often times there isn’t enough tissue to test. In these patients we often have to wait and see and if they end up with progressio. Of disease, they have to undergo procedure to procure more tissue. Patient often find distress in this process for they just have found out they have recurrent disease and now have to undergo a procedure for tissue for BRAF testing. If we can we try to at least do a IHC on tissue to see if we can get BRAF results.

[Anonymous]

I’m also really hoping that there will be a push to educate referring providers (surgeons, particularly) to help save time, especially given that there can be a wait to get in the door for an appointment at some institutions. Of course the surgeons that we routinely work with will be aware, and it will probably become a default with the pathologists at our institution, but in the community, this will certainly be important.

[Anonymous]

You all make excellent points. I would suspect Guidelines will be soon include when when patients’ should have their tumor sent for molecular analysis. As a general role, we have been testing anyone with a Stage IIB or greater, knowing that the likelihood of relapse is high. The primary lesion is used. Having this information in our “pocket” in case….has saved time for those patients who have aggressive relapses. If not enough tissue is available or there is other concern for not proceeding with testing, we know that up front.

In an ideal world, having this knowledge expedites evaluation….but as we all know, we do not always live in an ideal world!

[Mandi Murph]

We don’t routinely check our IIB pts or primary lesions, we will check the primary lesion if the tissue from nodes is QNS and there is no other source of sampling or if safety is an issue wtih a new issue in sampling.
Although primary tumors may possess BRAF mutations, they don’t always 100% of the time correlate to metastatic sites, so checking new advanced disease against a high risk primary result would be prudent. As Rajni mentioned a quick 24 hour turn around with tissue IHC for BRAF can be conducted while conducting a full genetic analysis, especially if the start of treatment is urgent. I agree Krista, we will be seeing more sampling in earlier high risk disease, thank you for sharing your routine practice.

[Author]

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