Author Affiliations: Departments of Dermatology (Drs Díaz Moreno, Domínguez-Cruz, Quintana, and Conejo-Mir) and Pathology (Dr Zulueta), Hospitales Universitarios Virgen del Rocio, Sevilla, Spain.
Dermoscopy has clearly improved diagnosis of pigmented skin lesions. By virtue of the special architecture of the epidermis on palms and soles, these locations have specific patterns. Parallel ridge pattern (PRP), a bandlike pigmentation on the ridges of the surface skin markings, is a highly characteristic dermoscopic pattern of acral melanoma. However, it can be detected in a few benign conditions.
A 47-year-old woman was referred to our department for evaluation of a pigmented lesion of 1 year's evolution on the sole of her left foot. Previously, diagnosis of a viral wart had been made, and the wart was treated with cryotherapy by her primary care physician on 15 occasions, the last treatment 3 weeks prior to presentation at our department. The patient was uncertain of having had any pigmentary lesion at this level before undergoing cryotherapy treatment.
Moreno RD, Domínguez-Cruz J, Zulueta T, Quintana J, Conejo-Mir J. Parallel Ridge Pattern Due to Cryotherapy Treatment. JAMA Dermatol. 2013;149(4):491-493. doi:10.1001/jamadermatol.2013.2346