α-Gal syndrome is a general term for allergies to red meat, cetuximab, and flounder roe caused by tick bites. Among these, cetuximab allergy is the most severe, potentially leading to anaphylactic shock after the first infusion. In 2014, 4 of 13 patients with head and neck cancer at Matsue Red Cross Hospital developed severe anaphylactic shock after they received the first administration of cetuximab.
To prevent cetuximab-induced anaphylaxis and establish a cutoff value for α-Gal-specific IgE.
Besides the 13 patients who received cetuximab without prior allergy testing (non-intervention group), the study also included 205 new patients with head and neck cancer who were potential candidates for cetuximab (intervention group). Of 205 new patients, 39 with α-Gal-specific IgE below 0.35 UA/mL by CAP-FEIA were administered cetuximab based on their cancer progression and general condition and were observed for anaphylaxis development.
Four patients in the non-intervention group developed anaphylactic shock, all of whom had α-Gal-specific IgE levels ≥0.35 UA/mL (incidence 30.8%). Three of the 39 patients in the intervention group developed anaphylactic shock (incidence 7.7%). ROC analysis in all patients who received cetuximab in the non-intervention and intervention groups determined that the optimal cutoff value for α-Gal-specific IgE was 0.14 UA/mL, with a sensitivity of 86% and a specificity of 98%. Of the 218 participants, 20 tested positive for α-Gal-specific IgE (9.2%). A 0.14 UA/mL cutoff value revealed that 32 of 218 participants (14.7%) had detectable α-Gal specific IgE.
We must exercise heightened caution regarding the potential for α-Gal syndrome when using products derived from mammals and other products, particularly pharmaceuticals.