Methods: We studied 12 patients with gastrointestinal and OBGYN cancers who presented hypersensitivity reactions to platins and 6 healthy volunteers who had never been exposed to platins. Skin testing and BAT were done before RDD to platins, and the expression of activation markers CD203c and CD63 was evaluated on basophils (HLADR-/CD41-/CD123+). Most patients were evaluated during 2 or more RDD procedures.
Results: BAT was positive in 9/12 patients (75%), with increased expression of CD203c (9 patients) and CD63 (4 patients). The BAT positivity was 66,7% (6/9) for carboplatin and 100% (3/3) for oxaliplatin. Subsequent BAT analysis in different RDD procedures showed that the test remained positive before each procedure with an even greater expression of CD203c and CD63, indicating temporary tolerance during RDD, which was lost after each exposure. In an attempt to correlate reactions during RDD with specific BAT markers, we observed an association between CD63 expression and the severity of the reactions. All controls had negative tests. Further studies are needed to determine the predictive values of BAT in patients with platins hypersensitivity.
Conclusions: We standardized a BAT to platins with good sensitivity and which can predict patients with severe reactions during RDD. RDD to platinum drugs does not induce persistent hyporresponsiveness on basophils, highlighting the need to maintain repeated RDD in allergic patients to platins.