Clinical science letters

To the Editor: Capecitabine is a chemotherapeutic agent of the fluoropyrimidine family, indicated in metastatic colorectal cancer and advanced breast cancer. Its main cutaneous adverse effect is hand-foot syndrome (HFS); cases of skin hyperpigmentation, nail changes, and alterations of the mucosas secondary to this drug have also been reported. Capecitabine is converted to 5-fluorouracil by the enzyme thymidine phosphorylase, which is found in its highest concentration in tumor tissue. The drug is administered orally and its systemic adverse effects are less severe than those of 5- fluorouracil.1 We present 2 new cases of toxic dermatitis due to capecitabine where, in addition to HFS, there were localized skin hyperpigmentation and marked nail changes. The patients were 2 men of 53 and 79 years of age, diagnosed with Duke stage III adenocarcinoma of the colon. After laparoscopic sigmoidectomy, they started adjuvant treatment with capecitabine (Xeloda), the first at a dose of 4000 mg/d and the other at 3000 mg/d. The first patient was seen after the third cycle of chemotherapy, with a 15-day history of skin lesions affecting the palms of the hands, with no associated palmar-plantar dysesthesia. On physical examination, we observed brownish macules of 0.3 cm diameter on both palms, associated with marked desquamation, periungual hyperpigmentation, and moderate erythema of the distal phalanges (Figure 1). The second patient reported palmar-plantar erythema and erosions that started after the second cycle of capecitabine. Examination revealed intense palmar-plantar erythrosi