Introduction: Basal cell carcinoma is the most prevalent form of cancer worldwide, usually arising in the head and neck region, which is cured by surgical excision and rarely invades or metastasizes. Many reports exist of bony invasion in the head and neck but very rarely into long bones.
Methods: We report an unusual case of basal cell carcinoma that despite surgical excision, directly invaded the left humerus. This article also includes a literature review with possible explanations for the occasionally aggressive behavior of basal cell carcinoma.
Results: This 68-year-old patient underwent wide resection of the affected left upper arm skin, tissue, and diaphyseal segment with clear margins. The defect was reconstructed with a vascularized free fibula bone graft, pedicled latissimus muscle flap, and split-thickness skin graft.
Conclusions: Long bone invasion by BCC is extremely rare and not well reported. There are more biologic explanations for overtly aggressive behavior that BCC may exhibit such as in this case.
Keywords: basal cell carcinoma; bone invasion; long bone invasion; nonmelanoma skin cancer; skin cancer.