Additional copies of ALK gene locus detected - 1253731

The ALK testing is based on a threshold of a certain level of copies (in 15% of nuclei) of the ALK rearrangement being detected, and above it, testing is called positive. To my knowledge, it isn't known whether having some lower level of detectable ALK rearrangement means anything for predicting response to crizotinib, nor for the probability of another "driver mutation". Up to this point, less than the defined threshold of ALK rearrangement is simply considered "negative" for the purposes of research on molecular testing in NSCLC.

-Dr. West

Hello Chaya,
This transcript should provide enough of a biology lesson about ALK gene rearrangement to feel comfortable about moving forward with molecular screening for your mum and being sure the proper testing has been done for ALK.
http://cancergrace.org/lung/files/2011/10/dr-solomon-alk-inhibition-sci…

The following posts are on molecular testing in general and I think will provide an understanding without delving so deeply into the biology that moves away from our focus of what tests and treatment is best.
http://cancergrace.org/cancer-101/2012/11/30/path-and-mol-pat/
http://cancergrace.org/lung/tag/molecular-screening/
http://cancergrace.org/cancer-101/tag/molecular-testing/

We have an extensive library that I find best accessed by using our search feature. Note you may need to log off to access it depending on your browser. I didn't come across any info about your particular question about ALK gene locus’. That doesn't mean you shouldn't ask but it does probably mean you should read what the experts and sophisticated members have discussed on the matter.

I hope this helps,
Janine
forum moderator

I don't think it was particularly helpful of the testing lab to have worded their report so that even the oncologist couldn't understand it. It seems to me that you have two choices: either take his/her word for it or, if you want a fuller picture, contact the testing lab for clarification from a pathologist, asking the question you have just asked - does it have any bearing on testing for ROS. Best to you and your mother.

Sorry to be a pessimist here, but I would be floored if someone at the lab actually has a meaningful answer. They probably didn't write the wording on the reports and wouldn't have any more insight.

-Dr. West

Peter Mac and Dr. Solomon have been among the leaders in the world in a lot of targeted therapies in lung cancer, and especially work on ALK, so if there's anyone who could answer your detailed questions, it's him.

Good luck.

-Dr. West