Young Man With "Insect Bites" on His Back

A 26-year-old African American man was found to have asymptomatic, erythematous, non-scaling plaques on the neck and upper back. He thought that the lesions were most likely insect bites.

Samples were taken for biopsy. A chest radiograph showed bilateral hilar adenopathy, but no parenchymal disease. Pulmonary function test results were normal, as was serum calcium level.

What do you think the biopsy showed?

For the correct diagnosis, see the complete description of the case.