Management of Patients with Suspected Hypersensitivity to Chemotherapy Drugs: A Practical Approach in a Tertiary Care Setting

Background: Hypersensitivity reactions to antineoplastic agents are an increasing clinical challenge due to their rising incidence and potential severity. Early allergological assessment and tailored drug re-exposure strategies may allow continuation of essential therapies, although real-world data remain limited. Methods: We conducted a monocentric retrospective observational study including adult oncologic patients with suspected chemotherapy-induced hypersensitivity reactions. Clinical features, allergological work-up, and management strategies were analyzed. The primary outcome was the success rate of drug reintroduction using desensitization or enhanced premedication. Secondary outcomes included skin test positivity rates and the association between cumulative chemotherapy exposure and anaphylaxis. Results: Forty-two patients were included (95% female; median age 57.5 years). Re-exposure was required in 18 patients, and was successful in all patients undergoing desensitization and in 92% of those managed with enhanced premedication. Skin testing was positive in 71% of suspected platinum reactions, 30% of taxanes, and 40% of biologic agent reactions. Anaphylaxis occurred in 26.2% of patients, and a trend toward an association with cumulative chemotherapy exposure was observed; each additional cycle was associated with a 28% increase in the odds of anaphylaxis (adjusted OR 1.28; 95% CI, 1.00–1.63). Conclusions: Desensitization and enhanced premedication allow safe reintroduction of antineoplastic agents. Cumulative chemotherapy exposure is associated with an increased risk of anaphylaxis.