Onychomadesis and onycholysis associated with capecitabine

Sir, Onychomadesis may be idiopathic or may be associated with systemic lupus erythematosus, pemphigus vulgaris, mycosis fungoides, alopecia areata universalis, epidermolysis bullosa, toxic epidermal necrolysis, keratosis punctata palmaris et plantaris, thrombocytopenia, neurological disease, peritoneal dialysis, penicillin anaphylaxis, infection, radiation therapy or drug adverse effects.1,2 Onycholysis has been found in many conditions, including treatment with antineoplastic drugs, thyroid disease, pregnancy, syphilis, atopic dermatitis, infections and chemical intoxication.3 We describe a case of onychomadesis and onycholysis caused by capecitabine. A 72‐year‐old Taiwanese woman with breast cancer and bone metastasis had been treated with modified radical mastectomy, radiotherapy and numerous antineoplastic agents including cyclophosphamide, methotrexate, 5‐fluorouracil (5‐FU), mitomycin‐c, vinblastine, tamoxifen, taxoid and adriamycin. Due to a recalcitrant course, the above therapeutic agents were discontinued and she was given solely capecitabine (Xeloda®, Roche) 1500 mg twice daily for 2 weeks at 3‐weekly intervals. Four months later, nail dystrophy was noted with leuconychia and onycholysis of the right middle, ring and little fingers, and onychomadesis of the left middle and ring fingers and both great toes (Fig. 1). Repeated potassium hydroxide examination of the nails did not show fungal hyphae. Capecitabine was continued over the following 7 months because of advanced breast carcinoma with multiple metastases. Onycholysis and onychomadesis persisted until cessation of capecitabine for 2 months.