A 2-year-old boy presents with a rash. On physical examination, he has a crusty, red skin lesion at the hairline and on the extensor surfaces of his extremities and abdomen. Exophthalmos is noted. An X-ray film of the head shows multiple, radiolucent lesions in the skull. A biopsy of one of the skull lesions shows large, plump cells with pale, eosinophilic, foamy cytoplasm and convoluted nuclei (shown in the image). What is the most likely diagnosis?
(A) Ewing sarcoma
(B) Giant cell tumor of bone
(C) Hand-Schüller-Christian disease
(D) Large B-cell lymphoma
(E) Multiple myeloma
C. Hand-Schuller-Christian disease