Evaluation of basophil CD203c as a predictor of carboplatin-related hypersensitivity reaction in patients with gynecologic cancer.

The incidence of hypersensitivity reaction (HR) to carboplatin has been reported to increase after repeated use of the drug. However, a reliable ex vivo test to predict HR to carboplatin is not currently available. We evaluated the clinical usefulness of measuring basophil CD203c to predict carboplatin-related HR in this prospective case-control study conducted at Mie University Hospital between October 2009 and September 2010. Eleven patients had history of carboplatin-related HR within the past 3 years, and 19 had no history of HR after receiving more than 5 courses of carboplatin therapy. Six of these 19 patients developed carboplatin-related HR during the study period. The CD203c+ basophils (%) and the mean fluorescence intensity (MFI) were analyzed on a flow cytometer and compared between patients with and without HR. Changes in the CD203c expression on basophils before and after HR were also assessed in patients who developed HR during the study period. The median CD203c+ basophils (%) and ΔMFI after 30-min exposure to 50 µg/mL carboplatin were significantly higher in patients with HR (3.5% and ΔMFI 9.0) compared with those without (2.2% and ΔMFI 0.4) (p<0.05). In particular, these values were significantly higher in patients with grade 4 anaphylaxis (10.6% and ΔMFI 22.0). All five patients who developed grade 2-4 anaphylaxis during the study period had high CD203c+ basophils (%) and/or increased ΔMFI on the day before HR. The results suggest that basophil CD203c may be a promising biomarker for the prediction of severe carboplatin-related anaphylaxis.