A Destructive Tumor of the Proximal Tibia and Fibula: A Case Report Highlighting Challenging Diagnosis and Treatment of a Locally Advanced, Non-recurrent Chondroblastoma in 16 Years Old Patient.

Introduction: Chondroblastoma is a rare, cartilaginous primary bone tumor, which presents predominantly in children and young adults. These tumors represent 1% of all primary bone tumors. Patients tend to complain of progressive joint pain which usually aids in early diagnosis. However, early diagnosis has made the understanding of the untreated, progressive course of chondroblastoma quite difficult. This case report highlights a patient who was first encountered with locally advanced chondroblastoma and discusses the challenges of diagnosis and treatment with a focus on the natural progression of this disease.

Case Report: We report the case of a 16-year-old male encountered during relief efforts after the 2010 Haiti earthquake, who was found to have a massive, expansile, and destructive mass of the proximal left tibia and fibula. Radiographic appearance was concerning for a malignant bone forming process. However, biopsy revealed features most consistent with chondroblastoma with secondary aneurysmal bone cyst formation. Marginal resection was considered, but the degree of soft tissue and neurovascular invasion made it impossible to salvage the leg and thus an above-the-knee amputation was performed.

Conclusion: This report reviews the challenging diagnosis of a massive chondroblastoma with locally aggressive features which required ablative surgery. This may provide insight into the untreated, natural course of this pathology.