Low Eosinophil Percentages as a New Predictive Marker for Infusion Reactions Due to Trastuzumab.

BACKGROUND/AIM: Infusion reactions (IRs) often occur with trastuzumab. Although premedication by non-steroidal anti-inflammatory drugs can be effective to a certain extent, IRs are still common and infrequently severe. Therefore, a predictive marker that can select patients requiring further prophylaxis is useful for appropriate prevention, but remains unclear.

PATIENTS AND

METHODS

We conducted a retrospective analysis for 136 consecutive female inpatients aged 18 years and older who received 8 mg/kg of the initial trastuzumab administration for breast cancer with a 25-mg dose of rectal diclofenac before trastuzumab infusion between May 2007 and April 2019, in order to assess IRs.

RESULTS

Overall, 57 patients were eligible for inclusion in the study. IRs were observed in 17.5% (10/57) of the patients. Univariate analysis showed that patients with a low eosinophil percentage (≤2%) were associated with IRs (p=0.016).

CONCLUSION

A low eosinophil percentage can be a useful new predictive marker for trastuzumab-induced IRs in patients with breast cancer.