During the administration of chemotherapy drug-related toxic effects are common, and occasional, allergic reactions have been reported. The platinum salts are known sensitizers mainly triggering anaphylactic reactions. We present 2 cases of delayed cutaneous rash after cisplatin and oxaliplatin administration.

Patient 1.- A 60 year-old man, diagnosed of ganglionar metastasis of an unknown primary tumor, suffered eight hours after the 3rd weekly course of intravenous cisplatin, an itching erythematous eruption on his arm. It recurred during the following cycle. Patient 2.- A 66 year-old man, diagnosed of rectal carcinoma, suffered 24 hours after the 1st course of intravenous oxaliplatin a non-itching erythematous eruption on the neck. It relapsed during the 2nd course. Both reactions improved after oral antihistamines and steroids. Prick (10 and 1 mg/ml) and intradermal (1 mg/ml) tests were performed.

Skin prick tests were negative in both cases. The intradermal tests were followed by no immediate reaction, but a delayed erythemato-infiltrative response appeared 24 hours later (7 × 6 mm & 5 × 4 mm). Patient 2 also developed a relapse of the cervical rash. Anatomopathological studies of the intradermal tests revealed moderate vasodilatation, edema and an infiltrate of lymphocytes and eosinophils in dermis in patient 1, and epidermic focal parakeratosis with irregular acanthosis with vasodilatation and a moderate limphohistiocytic infiltrate in dermis in patient 2.

We report 2 cutaneous delayed reactions due to intravenous platinum salts. A delayed type hypersensitivity reaction to cisplatin and oxaliplatin is suggested. To the best of our knowledge these are the first reported cases.