Photo Rounds
Hands with erythematous patches
A 49-year-old Caucasian man sought care for erythematous patches on the dorsal surface of his hands that he’d had for 2 to 3 years. These patches...
Histologically, EAI is similar to actinic keratosis, with epidermal changes showing squamous atypia.2 Due to the similarities, these lesions are sometimes referred to as “thermal keratosis.” Some researchers have suggested that the thermal heat may induce epithelial changes in the same way that ultraviolet light produces epithelial changes.7
Rarely, EAI can turn into cancer. There have been a few reported cases of EAI transforming into squamous cell carcinoma or Merkel cell carcinoma; squamous cell carcinoma is more common, and tends to occur after a long latent period (up to 30 years).7-9 EAI lesions often begin as a chronic ulcer and tend not to heal. If the lesion continues to evolve (ie, ulcerate), a biopsy may be warranted to rule out a malignant transformation.
Eliminate heat exposure, consider a topical treatment
Treatment of acute EAI involves eliminating the offending heat source. The hyperpigmentation will slowly resolve over months to years.4 Persistent exposure to heat sources can lead to chronic EAI, which is more difficult to eliminate.
Because hyperpigmentation can be visually unappealing and emotionally distressing, some patients prefer active treatment. EAI has been effectively treated with 4% hydroquinone topical cream twice a day and tretinoin topical cream at night.2,10,11 Lesions that have epithelial atypia have improved with 5-fluorouracil topical cream.7
EAI also has been successfully treated with laser therapy with the 1064-nm Q-switched Nd:YAG laser with low fluence at 2-week intervals.9
Our patient declined topical therapy. He improved after a few months of avoiding the heater under his desk.
CORRESPONDENCE
Megan Morrison, DO, 5333 McAuley Drive Suite R-5003, Ypsilanti, MI 48197; memorrison10@gmail.com
