Diagnostic and predictive value of skin testing in platinum salt hypersensitivity

Background: Hypersensitivity reactions to platinum salts are potentially lethal adverse events in chemotherapy, and often require its discontinuation. Several preventive procedures have been proposed: premedication, desensitization regimens, or replacement with a different platinum salt. Objective: We therefore assessed the value of skin tests with platinum salts. A positive result would confirm their responsibility in hypersensitivity reaction, whereas a negative result would identify candidates for continuation of therapy using a different platinum salt. Methods: Patch tests, prick tests, and intradermal tests with cisplatin, carboplatin, and oxaliplatin were performed in 21 patients. Results: Skin tests were positive in 14 of 21 cases. Prick tests were positive in 5 cases with the suspected platinum salt. Intradermal tests were positive in 12 of 19 cases, always when the hypersensitivity occurred less than 2 hours after infusion. Cross-reactions were observed in 4 cases. Delayed readings of skin tests at 24 hours and 48 hours were positive in 3 patients. Patch tests were negative in all the 21 patients tested. Replacement with another platinum salt was performed in 13 patients using one that gave a negative skin test. A relapse of symptoms occurred in 1 patient. Conclusion: Intradermal tests are particularly indicated for the diagnosis of immediate hypersensitivity reaction. Their good negative predictive value allows safe retreatment by detecting a potential cross-reaction. Clinical implications: The frequency of cross-reactions among cisplatin, carboplatin, and oxaliplatin has not been clearly established. Skin tests allow different platinum salts to be given and avoid discontinuation of chemotherapy.