Benign dermoscopic parallel ridge pattern in plantar hyperpigmentation due to capecitabine

We report the case of a 37-year-old woman (phototype II) who presented at our outpatient clinic with a two-month history of hyperpigmented plantar macules. Medical history revealed that the patient had taken capecitabine in the past three months as adjuvant chemotherapy for recurrent breast cancer. Dermoscopic examination of the plantar macules showed parallel ridge pattern with pigmentation in the furrows without obliteration of eccrine gland apertures. Besides in acral melanoma, parallel ridge pattern can also be observed in benign plantar lesions, such as congenital or acquired acral nevi, subcorneal hemorrhage, dye-related pigmentation and drug-induced hyperpigmentation, especially in patients with phototypes III-VI. The few reported cases of capecitabine-induced hyperpigmentation have been associated with hand and foot syndrome in patients with phototypes IV-V and palmar as well as plantar involvement.