Carboplatin and Cisplatin are powerful alkylating agents. We were consulted on 7 pt with ovarian cancer who had developed adverse reactions to Carboplatin. All 7 pt developed their reactions after having tolerated many previous courses. The spectrum of reactions included pruritus, urticaria, angioedema, flushing, nausea, diarrhea, hypertension, hypotension, and fever. Skin test with Cisplatin or Carboplatin were negative in 6/7 pt whose reactions occurred more than 1 year ago and was positive in the patient who had severe reaction within 2 months of testing. All 6 skin test-negative pt underwent successful desensitization/challenge of Cisplatin (4) or Carboplatin (2) under a continuous IV protocol of rapid escalating doses. 3/6 pt were maintained on a daily IV low dose protocol with excellent tolerance though all 3 developed Fanconi's syndrome. 2/6 pt tolerated subsequent infusions every 2-3 wks under an accelerated protocol. 1/6 pt developed urticaria, flushing, and abdominal discomfort on the accelerated protocol, completed the infusion with slowing down of the protocol and with additional antihistamines. A serum tryptase level drawn during the reaction was markedly elevated. Skin test to Carboplatin prior to the 3rd infusion showed a +ve conversion. She was successfully desensitized using the original slower protocol complicated by a mild urticarial reaction.

Hypersensitivity reactions may occur to Carboplatin/Cisplatin after prior sensitization, mediated by IgE and mast cell degranulation at least in some pt. Skin test is more likely to be positive if the reaction was recent and may be helpful prior to repeat desensitization/challenge.