[A female runner with a painful knee].

Area of Science:

• Orthopedic oncology
• Radiology
• Pathology

Background:

• Giant cell tumors (GCTs) are typically benign bone neoplasms.
• Distal femur involvement is common in GCTs.
• Early and accurate diagnosis is crucial for effective management.

Observation:

• A 36-year-old healthy female presented with left knee pain.
• Radiographic examination revealed a lytic lesion in the distal femur.
• Magnetic Resonance Imaging (MRI) confirmed the lesion and indicated a high suspicion for GCT.

Findings:

• The imaging findings were highly suggestive of a giant cell tumor of bone (GCTB).
• The tumor was located in the distal femur, a common site for GCTB.
• The patient was referred to a specialized center for further management.

Implications:

• Prompt diagnosis and treatment of GCTB are essential to prevent pathological fractures and preserve joint function.
• Multidisciplinary management involving orthopedic oncologists, radiologists, and pathologists is recommended.
• Further histological evaluation is necessary to confirm the diagnosis and guide treatment strategies.