Derm Dx: Bumps on the leg 10 years after cancer surgery

An 84-year-old female complains of bumps that developed on her right lower leg several months ago.  She had salivary gland cancer that was diagnosed and surgically excised 10 years ago. Subsequently, she has been followed at yearly intervals by an oncologist.  Examination of the affected ankle revealed scattered erythematous firm papules, slightly tender to palpation. A ...