case_images: PMC10870126_01
case_images: a, b Clinical photograph of patient's left proximal tibia at presentation. He had arrived with a wound vacuum dressing with black sponge directly applied to the tissue seen here. The ulcer measured 13 cm cranio-caudal and 8 cm medial-lateral. a The area marked "T" is exposed tibia, which was desiccated. Initial bedside punch biopsy findings prompted surgical biopsy. These included soft tissue biopsies taken from the four locations marked "B" (two edges of the skin and ulcer, and two deep tissue sections central in the wound) and also two core bone biopsies taken from an area without skin involvement, approached from the medial proximal tibia just beneath the plateau, marked C.
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case_images: PMC10870126_01_cro-2024-0017-0001-536445_F01.jpg
case_images: F1
case_images: A 70-year-old Caucasian male was transferred to the orthopedic service from an outside hospital for management of a large chronic ulcer of his left pretibial skin, measuring 13 cm cranio-caudal, 8 cm medial-lateral, and deep to underlying muscle compartments and with desiccated tibia exposed (shown in Fig. 1).
case_images: Imaging of the left tibia. Anterior-posterior (a) and lateral (b) radiographs identify that the proximal third tibia has substantial mottling but a relatively normal remainder of the tibia. The coronal (c) and sagittal (d) MRI identifies that the entire proximal tibia is involved, with air present posterior to the tibia, with nearly no uninvolved sub-plateau tibia. There is no evidence of disease in the knee joint or femur. MRI, magnetic resonance imaging.
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case_images: PMC10870126_01_cro-2024-0017-0001-536445_F02.jpg
case_images: F2
case_images: A radiograph and magnetic resonance imaging of the tibia were obtained to better understand the extent of bone and soft tissue involvement (shown in Fig. 2).
case_images: Hematoxylin and eosin staining of surgical biopsy microscopic pathology descriptions. a, b Soft tissue samples seen at x10 light magnification. There is extensive infiltrating basaloid tumor with ulceration. The cells also have abundant glycogenated clear cytoplasm. The ulcer shows an extensive infiltrating basaloid tumor. The tumor cells have palisading and also exhibit abundant clear cytoplasms. There are pigment-laden macrophages noted throughout the dermis. c is at x4, and (d) and (e) are x10 and x20 bone tissue, respectively. The marrow appears fibrotic with minute atypical cellular fragments. There is tumor infiltrating the marrow, which is consistent with infiltrative BCC. There are cords and islands of malignant epithelium with necrosis infiltrating the fibrotic marrow. There is marrow replacement by sclerotic stroma. Infiltrating the marrow are islands of BCC that assume an irregular infiltrative growth pattern.
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case_images: F3
case_images: An initial punch biopsy noted apparent BCC, which prompted a confirmatory surgical biopsy of multiple sites (shown in Fig. 3) to confirm diagnosis, which indeed was confirmed.