Unusual Presentation of Solid-Variant Aneurysmal Bone Cysts as Primary Digital Skin Lesions: A Case Series...

Area of Science:

• Orthopedic Oncology
• Dermatopathology
• Radiology

Background:

• Solid-variant aneurysmal bone cysts (ABC) are rare benign bone neoplasms.
• They lack the typical cystic spaces of classic ABCs and can occur in unusual locations like the distal extremities.

Observation:

• This study reports three cases of solid-variant ABCs presenting as skin-associated masses on the fingers.
• These lesions posed diagnostic challenges due to their resemblance to common dermatologic conditions such as pyogenic granuloma.

Findings:

• Initial shave biopsies showed nonspecific granulation tissue-like material.
• Radiologic imaging revealed distal phalanx lucencies with extraosseous extension.
• Surgical specimens confirmed classic solid-variant ABC features: (myo)fibroblastic spindle cells, giant cells, woven bone, and hemorrhage.

Implications:

• Radiologic correlation is vital for pathologists when evaluating cutaneous masses with potential bone involvement.
• Accurate diagnosis through combined histopathology and radiology is critical for proper management of solid-variant ABCs.
• This highlights the importance of interdisciplinary collaboration in diagnosing rare bone tumors with atypical presentations.