Derm Dx: Multiple white papules on the penis

A 30-year-old African-American man is evaluated for lesions on his penis. He states that the lesions have been present since adolescence, and he has had 2 work-ups for sexually transmitted diseases. He denies symptoms. Recent rapid plasma reagin and HIV assays were negative, and a complete blood count is unremarkable. Treatment with imiquimod cream did not produce any visible result. ...