Comparison between hypersensitivity reactions to cycles of modified FOLFOX6 and XELOX therapies in patients with colorectal cancer

Purpose: Although hypersensitivity reactions (HSRs) to oxaliplatin (L-OHP) therapy are well-documented, few reports have compared different therapies in terms of HSR occurrence. In this study, we compared the frequency and pattern of HSRs to modified FOLFOX6 (mFOLFOX6; 5-fluorouracil, levofolinate calcium and L-OHP infusions) and XELOX (capecitabine and L-OHP) therapies, and sought to identify risk factors associated with HSRs. Methods: Patients who had received mFOLFOX6 or XELOX chemotherapeutic regimens for unresectable colon or rectal cancer or as adjuvant chemotherapy following colon cancer surgery between April 2012 and August 2015 were included. Potential correlation between treatment modalities (regimen, dosage and route of administration of L-OHP, and injection timing for dexamethasone administration) and HSRs was assessed. Results: Among the 240 patients included in the study, 136 had received mFOLFOX6 therapy and 104 had received XELOX therapy. Although the frequency of HSRs did not differ between the two groups, incidence of HSRs in the first cycle was higher in the XELOX therapy group. Treatment method or cumulative dosage was not identified as a risk factor for HSR; however, the incidence of ≥grade-2 HSR was higher in cases where the cumulative L-OHP dosage was ≥600 mg/m² and in patients in whom dexamethasone was not co-infused with L-OHP. Conclusion: Although HSR rates were comparable among patients treated with mFOLFOX6 and XELOX, HSRs tended to occur more frequently during the first cycle of XELOX therapy as compared to that with mFOLFOX6 therapy. Our findings warrant careful assessment of ≥grade-2 HSRs in patients who are prescribed cumulative L-OHP dosages of ≥600 mg/m².