Synonyms

• BFH
• fibrous histiocytoma of Bone

Category

Bone

Behaviour

Benign

Gender

Both equally

Tissue of Origin

Fibrous

Epidemiology

• Rare tumour accounting for <1% of primary Bone tumours
• Wide age range but peak incidence in 2nd–4th decades
• No significant gender predilection

Clinical Features

• Usually presents with pain and swelling
• May be asymptomatic and incidentally discovered
• Rarely causes pathological fracture

Location

• Femur most common
• Tibia
• Pelvis and flat Bones occasionally

Imaging

• Geographic lytic lesion with well-defined sclerotic margins
• No periosteal reaction in most cases
• May show cortical thinning or expansion
• No matrix mineralisation

Pathology

• Storiform pattern of spindle cells
• Histiocyte-like cells and giant cells present
• Foamy macrophages frequently seen
• Low mitotic activity

Genetics

• No recurrent cytogenetic abnormalities identified
• Polyclonal lesion in most cases

Treatment

• Curettage with or without Bone grafting
• Extended curettage with adjuvants (phenol, liquid nitrogen) for recurrent lesions
• Wide excision reserved for aggressive or recurrent cases

Prognosis

• Excellent prognosis after complete excision
• Local recurrence rate approximately 10–20%
• Malignant transformation exceedingly rare

Key Points

• Diagnosis of exclusion - must rule out Malignant Fibrous histiocytoma and other Fibrous lesions
• Histologically identical to soft tissue counterpart
• Close Follow-up recommended due to recurrence risk

Workup - Blood Tests

FBC, U&E, LFTs, Bone profile - pre-operative baseline

Workup - Local Imaging

• Plain radiograph - geographic lytic lesion with well-defined sclerotic margins
• MRI primary site - characterise lesion and exclude Malignant features
• CT - cortical integrity assessment

Workup - Biopsy

• Core needle biopsy or excision biopsy - diagnosis of exclusion
• Histology: storiform spindle cells, histiocyte-like cells, multinucleated giant cells, foamy macrophages
• IHC panel to exclude: MDM2/CDK4 neg (not WD liposarcoma), CD34 (solitary Fibrous tumour), STAT6 (SFT)
• Exclude non-ossifying fibroma (NOF) clinically - very similar histology

Workup - Staging

No staging required - Benign tumour

Workup - Other

MDT discussion - extensive IHC panel required to confirm diagnosis of exclusion

Follow-up Summary

• Post-op visit within 6 weeks; plain X-ray at 6 weeks to confirm healing
• Year 1: 6-monthly clinical review with plain X-ray to detect early local recurrence
• Year 2: Annual clinical review; plain X-ray if symptoms return
• Discharge at 2 years if no evidence of recurrence
• No CT or MRI routinely required unless recurrence suspected
• Recurrence (10–20%) should prompt repeat imaging (MRI) and MDT discussion
• Red flags: return of pain/swelling at original site, new pathological fracture