A 77 year-old man, in excellent health, developed bilaterally symmetrical lesions acutely while in Hawaii. His only medications are minocycline for scalp folliculitis and ketoconazole shampoo. The lesions literally developed within a day or two after being in Hawaii two weeks. He denied having a sunburn. He denied lesional or systemic symptoms. He did not recall applying anything to the sites prior to its appearance (not even sunscreen), other than his CPAP device, which he had been using for 6 months. I can confirm the acuteness of the lesions, as I saw him just prior to his vacation and there were no facial lesions. The lesions are depigmented patches on the cheek with slight erythema, extending onto the eyelid and temple. A distinct hyperpigmented macular border without scale is appreciated. KOH examination was negative Diagnostic considerations include acute vitiligo, chemical leukoderma (? to what), lupus, or doubtfully CTCL. I performed a biopsy from the edge for routine microscopy and DIF (results pending). Protopic was prescribed. I have never seen anything like this. The patient and I would be delighted if you have any good ideas. Thank you!