Palmar-plantar erythrodysesthesia (PPE) is a time-honored term in clinical oncology that has found its way into textbooks and public dictionaries. It accurately describes a typical adverse effect of continuous-infusion fluorouracil, oral capecitabine, and other cytotoxic anticancer agents. With time, the descriptive term PPE has been replaced with the term hand-foot syndrome (HFS), which is preferred for its simplicity.

With the advent of the multikinase inhibitors sunitinib and sorafenib, a new type of dermatologic toxicity has been recognized. It consists of callosities (thickened callous skin) that are usually in patchy distribution on palms and soles, mostly located where skin is subjected to particular pressure or strain (heel, ball, or above joints), often painful, and sometimes ulcerated or blistering. This type of dermatitis has been called hand-foot-skin reaction (HFSR).¹ Unfortunately, HFSR is being confused with HFS. Many oncologists have become negligent in this respect, calling any toxic dermatitis on the palms and soles HFS. This is clearly an undue medical simplification because the dermatitis induced by capecitabine is clearly different from the dermatitis induced by sunitinib or sorafenib both clinically and histologically and, most importantly, requires different dermatologic treatment.¹ Dermatologists should help us distinguish the two conditions, perhaps by using time-honored descriptive terms such as PPE. What then could be a descriptive term for HFSR? Should we call it palmar-plantar patchy callosities (PPPC)?