When would you consider additional testing for NUDT15 and other polymorphisms related to 6-MP/6-TG metabolism, if not guided by a study protocol?

My practice is to send a pharmacogenetic panel that includes TPMT and NUDT15 (as well as some other useful tidbits such as UGT1A! for Gilbert's syndrome) when patients with ALL are diagnosed.

The cost-effectiveness of this strategy has been addressed, with different conclusions (van den Akker-van Ma...

At diagnosis is best, but not always feasible.