A biopsy is also indicated for recurrent lesions or those unresponsive to therapy. Histologically, epidermal changes are present characterized by acanthosis and dyskeratosis. The keratinocytes vary in size and shape and have many mitotic figures. There usually is marked hyperkeratosis and areas of parakeratosis with a loss of the granular layer. A dense inflammatory infiltrate may be present.
Medical management begins with educating the patient to limit sun exposure.
They also must wear adequate sunscreens daily and protective clothing. As the lesions progress, they can be treated with topical 5-fluorouracil. This medication is applied twice daily for a period of three to four weeks for facial lesions. Other body sites require longer treatment with the arms needing six to eight weeks. It is best to treat the entire area of involvement.