A 54-year-old man is seen for evaluation of various skin problems, none of which he believes to be serious. His concern primarily stems from his job of 30 years, which keeps him outdoors most days with minimal protection from the sun.
In addition to the generally weathered skin on his sun-exposed arms and face, his wife has noticed redness around his neck and chest that is slowly worsening with time.
He denies any discomfort with the changes in his neck skin. He has a history of diabetes and smoking.
EXAMINATION
There is well-defined redness around his neck, especially in the front, that spills down onto his chest. Strangely, instead of matching the scoop neckline of the t-shirts he always wears, the chest redness is asymmetrical. It veers off to the patient’s left, sparing the midline chest. The erythema is partially blanchable with digital pressure but totally macular with no increased warmth.
What is the diagnosis?