Palmar psoriasis or missed BCC?-A case report

A 76-year-old Caucasian woman with a history of previous BCCs excised from the head and legs was referred from the dermatology team with a biopsy proven superficial BCC to the left palm. The patient had presented to the dermatology team with the same lesion 7 years prior to the definitive diagnosis. The lesion was described as 27 × 15 mm scaly, poorly-defined, plaque-like lesion to the central palm. There was no ulceration or visible telangiectasia. At the time, an initial diagnosis of psoriasis was given and she received several courses of topical treatments to no avail. Eventually, a biopsy was taken which revealed a multifocal superficial BCC. After unsuccessful attempts at treating with topical Imiquimod, the lesion was surgically excised and resurfaced with a full thickness skin graft.

The current understanding that BCCs derive from cells of the hair follicle cannot explain their appearance on the palm. Alternative hypotheses have been proposed as to their actual origin which would account for this rare occurrence. Ultimately, histology can determine the nature of the lesion. We urge clinicians encountering atypical, non-healing lesions to glabrous skin to keep in mind a diagnosis of skin cancer as a delayed diagnosis can lead to increased morbidity.