Background: Hypersensitivity reactions to chemotherapy disrupt treatment schedules and compromise patient outcomes. Rapid Drug Desensitization (RDD) enables patients to tolerate future treatments after an allergy workup. However, Same-Day Desensitization (SDD) is a novel approach that capitalizes on RDD to allow the continuation of chemotherapy on the same day as the index reaction, preventing treatment delays.Objective: To evaluate the safety and efficacy of SDD in managing hypersensitivity reactions during chemotherapy and emphasize the essential role of allergists in the Oncology Infusion Center (OIC) for accurate drugs hypersensitivity reactions (DHRs) phenotyping and management.Methods: This retrospective cohort included patients experiencing DHRs during chemotherapy. Under allergist supervision, SDD was performed once the index reaction was controlled. At a later date, clinical phenotypes and endotypes of DHRs were assessed through clinical history, skin tests, serum biomarkers (including tryptase and IL-6 levels), and drug provocation testing (DPT) to reach an accurate diagnosis.Results: SDD was successful in 35 cases, even for patients with severe initial reactions. Only 14% experienced breakthrough reactions, all mild. Same-day assessment by allergists ensured a 92% correlation between initial and final diagnoses, optimizing DHR management. Early engagement with Allergy allowed 86% of reactive patients to continue treatment through RDD or after ruling out an allergy.Conclusion: SDD is a safe and effective procedure that ensures that patients don't miss their oncology treatment on the day of a reaction. The presence of an allergist in the OIC is crucial for rapid access to accurate DHR phenotyping and optimal management, supporting personalized precision medicine in oncology.

Background: Rapid drug desensitization (RDD) allows first-line treatment to continue after a hypersensitivity reaction to the antineoplastic agent. There are different desensitization procedures, and none of them are free from breakthrough reactions (BTR). Objectives: The objective of the study is to evaluate and compare the efficacy of different desensitization procedures, considering the effect of a series of confounding variables, and to describe the characteristics of BTRs in different procedures. Methods: A retrospective, comparative review of medical records from patients who experienced hypersensitivity reactions to platinum- or taxane-based chemotherapy was conducted. Patients were categorized into two groups; rapid drug desensitization (RDD) and same-day desensitization (SDD), according to the intervention performed on the day of the initial reaction. Demographic data, drug, retreatment, cancer type, phenotype and severity of the initial reaction, allergy testing, number of desensitizations performed, outcome of desensitizations, and number, phenotype and severity of BTRs were recorded according to group. Results: In the RDD group, 406 desensitizations were analyzed in 76 subjects with a BTR rate of 24%. In the SDD group, 164 desensitizations were analyzed in 44 subjects with a BTR rate of 15%. A marginaleffects analysis using a Bayesian hierarchical model showed a 14.6-point reduction in the probability of BTR in the SDD group. Conclusion: This study confirms that desensitization procedures are safe and effective and allows us to conclude, based on the data and the model, that the SDD group has a lower probability of BTR than the RDD group.

Introduction: Hypersensitivity reactions to carboplatin include type I reactions, mixed reactions, and delayed reactions. Case report: We report a case of an atypical cytokine release syndrome induced by carboplatin in a patient with breast carcinoma. Management & outcome: The patient developed clinical manifestations consisting of a delayed cytokine release syndrome following administration of carboplatin and paclitaxel. To establish the diagnosis, she underwent a double desensitization protocol over two consecutive days with paclitaxel and carboplatin. A delayed elevation of interleukin-6 after carboplatin supported the diagnosis of an isolated cytokine release syndrome. The patient subsequently continued treatment with paclitaxel through standard infusions and with carboplatin using a desensitization protocol. Discussion: Cytokine release syndrome associated with carboplatin has been previously reported as occurring immediately after infusion and as part of a mixed phenotype (type I and cytokine release). A delayed-onset cytokine release syndrome induced by carboplatin, occurring outside the context of a mixed reaction, is reported. Conclusion: Cytokine release syndrome may present as an isolated, delayed reaction following carboplatin infusion. Measurement of interleukin-6 may be a valuable diagnostic tool for confirming the diagnosis of cytokine release syndrome.

Introduction: Laryngopharyngeal dysesthesia is considered an acute peripheral neuropathy secondary to oxaliplatin neurotoxicity. Case report: We report a case of laryngopharyngeal dysesthesia that developed in a patient with colon adenocarcinoma after receiving her third cycle of oxaliplatin. Management & outcome: She was treated with antihistamines, steroids, oxygen, and adrenaline and referred to the allergy department for investigation of a hypersensitivity reaction to the drug. Skin tests and tryptase extracted after the acute episode ruled out this possibility. However, the patient presented a slight elevation of interleukin 6, commonly observed in cytokine release reactions. The patient continued her oxaliplatin treatment with cautious administration and under the supervision of the allergist. Discussion: Laryngopharyngeal dysesthesia is part of oxaliplatin neurotoxicity and does not require discontinuation of the drug. However, in patients with severe laryngopharyngeal dysesthesia symptoms, it would be advisable to perform a differential diagnosis with hypersensitivity reactions and cytokine release reactions, whose management differs from neurotoxic reactions.