case_images: PMC7184841_01
case_images: Haemangioma on the anterior side of the left arm near the elbow joint.
case_images: cro-0013-0408-g01.jpg
case_images: PMC7184841_01_cro-0013-0408-g01.jpg
case_images: F1
case_images: Multiple scattered cutaneous vascular lesions had emerged in recent years (Fig. 1) and prompted excision surgery before.
case_images: Post-mortem histological images of the bone marrow. a Hypercellular intertrabecular space. H&E. x4. b Cell population with large eosinophilic cytoplasm and cerebriform nucleus. H&E. x20. c Positive immunohistochemical staining for CD1a marker. CD1a+. x20. d Electron microscopy showing "tennis-racket" cytoplasmic organelles characteristic of Birbeck granules. x40,000.
case_images: cro-0013-0408-g02.jpg
case_images: PMC7184841_01_cro-0013-0408-g02.jpg
case_images: F2
case_images: A post-mortem examination revealed bone marrow infiltration by large cells with an irregular core and large cytoplasm (Fig. 2a, b). Immunohistochemistry was positive for CD1a, S100, and CD5, and negative for markers of plasmacytic, B- and T-cell differentiation (Fig. 2c). Electron microscopy identified Birbeck granules (Fig. 2d).