What is the recommended treatment for a 6 cm endochondroma?

Treatment of 6 cm Endochondroma

A 6 cm endochondroma should be treated with wide surgical excision with negative margins due to its large size and increased risk of malignant transformation. 1

Assessment and Classification

When evaluating a large endochondroma (6 cm):

• Consider it potentially low-grade chondrosarcoma until proven otherwise
• Large size (>4.4 cm) is associated with higher risk of aggressive behavior
• Pain at the site of a cartilaginous lesion may indicate malignancy
• Contrast-enhanced MRI should be performed to reveal potential high-grade areas

Treatment Algorithm

Surgical Management

1. Wide excision with negative margins is the preferred treatment for large (6 cm) endochondromas due to:

   • Increased risk of malignant transformation
   • Higher likelihood of extracompartmental extension
   • Greater potential for local recurrence

2. Surgical approach depends on location:

   • For long bones of extremities: Wide excision with negative margins
   • For pelvis or axial skeleton: Wide surgical excision with wider margins (2 mm minimum for pelvis) 1
   • For hands/feet: More conservative approach may be considered as malignancy is extremely rare in these locations 1

Post-Surgical Management

• Fill defect with bone cement (polymethylmethacrylate) or cancellous bone graft
• Physical therapy consultation for mobility training and rehabilitation
• Regular surveillance imaging

Special Considerations

Location-Specific Approach

• Long bones: Wide excision with negative margins for 6 cm lesions 1
• Pelvis/axial skeleton: Always wide excision regardless of size 1
• Hands/feet: Even large lesions may be treated more conservatively with curettage as malignancy is rare 2, 3

Potential Complications

• Local recurrence (occurs in approximately 7% of surgically treated cases) 3
• Pathological fracture
• Functional limitations (more common with larger lesions and surgical treatment) 4

Follow-Up Protocol

• Physical examination and imaging of the lesion every 6-12 months for 2 years
• Then yearly imaging as appropriate
• Monitor for late recurrence, as this is more common with chondrogenic tumors 1

Important Caveats

• Larger lesions (>4.4 cm) have been shown to have worse functional outcomes after surgery compared to conservative treatment 4
• The differentiation between benign enchondroma and low-grade chondrosarcoma can be difficult, even among experts 1
• Patients with multiple enchondromas (Ollier disease) or Maffucci syndrome have higher recurrence rates and require more aggressive surveillance due to increased risk of malignant transformation 3

For a 6 cm endochondroma, the size alone warrants wide surgical excision with negative margins to ensure complete removal and minimize the risk of recurrence or malignant transformation, which is the approach most likely to reduce morbidity and mortality.