Rationale: A risk stratification protocol utilizing repeat skin testing (ST) was previously published in a small number of patients with carboplatin hypersensitivity reactions (HSRs). We studied this strategy in a larger number of patients with carboplatin or oxaliplatin HSR.
Methods: In a 5-year retrospective review, patients referred to Allergy/Immunology with carboplatin or oxaliplatin HSR were treated with a risk stratification protocol using 3 repeat STs with intervening desensitizations. If repeat ST remained negative three times, patients received subsequent infusions without desensitization.
Results: From 2008-2012, 144 patients (92 carboplatin, 52 oxaliplatin) completed 577 desensitizations. Carboplatin HSR patients were classified as ST positive (n=32), negative (n=37), or converters (n=23) when initial negative ST converted to positive on repeat ST. ST positive patients had more severe initial HSR than ST negative patients (p<0.05). Of the 52 oxaliplatin patients, 22 were ST positive, 25 were ST negative, 3 were ST converters, and 2 did not receive ST. For both carboplatin and oxaliplatin, ST converters had a longer time interval between HSR and initial ST compared to ST positive patients (carboplatin median 42 (IQR 2-96) vs 3 (IQR 2-8) weeks, oxaliplatin median 78 (IQR 40-92) vs 3 (IQR 1-5) weeks, p<0.05). Twenty-two carboplatin and 18 oxaliplatin HSR patients remained ST negative after three serial STs with intervening desensitizatons, and the majority (82% and 89%, respectively) completed their chemotherapy regimens as outpatient infusions without desensitizations.
Conclusions: Repeat STs improve care for patients with carboplatin or oxaliplatin HSR. Our novel risk stratification protocol identifies patients that can receive infusions without desensitization.