Synonyms

Elastofibroma dorsi

Category

Soft tissue

Behaviour

Benign

Gender

Female

Tissue of Origin

Fibrous

Epidemiology

• Pseudo-tumour / reactive Fibrous proliferation
• Peak incidence in elderly women (>60 years)
• Female predominance (10:1)
• Often bilateral (60%) - subscapular region
• Associated with repetitive mechanical trauma

Clinical Features

• Slow-growing firm mass in subscapular region
• Pain or discomfort with shoulder movement
• Often bilateral and symmetric
• Rarely symptomatic - often incidental imaging finding

Location

• Subscapular region (between serratus anterior and chest wall) virtually always
• Deep to inferior pole of scapula
• Occasionally other sites: ischium, olecranon

Imaging

• CT: lens-shaped or biconvex mass with alternating fat and soft tissue strands
• MRI: heterogeneous with fat signal interspersed with Fibrous stroma - 'striped' pattern
• Imaging characteristics are virtually diagnostic
• No enhancement on contrast CT

Pathology

• Dense collagenous Fibrous tissue with elastic fibre globules
• Elastic fibres appear as eosinophilic 'beads on a string'
• Intermixed mature fat
• No cellular atypia - reactive/degenerative process

Genetics

• No specific recurrent mutations
• Reactive rather than neoplastic proliferation
• Some chromosomal instability reported in elderly patients

Treatment

• Asymptomatic lesions require no treatment
• Surgical excision for symptomatic cases - curative
• Bilateral excision may be staged

Prognosis

• Excellent - Benign reactive lesion
• No recurrence after excision
• No Malignant potential

Key Points

• Virtually always in subscapular region - unique anatomical predilection
• Imaging characteristics alone are diagnostic in appropriate clinical setting - biopsy rarely needed
• Bilateral in majority - always examine opposite side
• Elderly women with repetitive shoulder activity (scrubbing, climbing) classically affected

Workup - Blood Tests

No blood tests required - clinical and imaging diagnosis

Workup - Local Imaging

• MRI
• Bilateral imaging - always assess contralateral subscapular region (bilateral in 60%)

Workup - Biopsy

• Biopsy NOT required if imaging is characteristic in correct anatomical site
• Core needle biopsy - only if imaging is atypical or location unusual
• Histology: dense collagen with elastic fibre globules ('beads on a string') and interspersed fat

Workup - Staging

No staging required - Benign reactive lesion

Workup - Other

• Surgical excision only for symptomatic lesions - excellent outcome
• No adjuvant treatment required

Follow-up Summary

• Post-operative review at 6 weeks
• No routine imaging required post-excision of confirmed elastofibroma
• Discharge with documented advice on self-monitoring for recurrence or contralateral development
• Contralateral elastofibroma: common (bilateral in 50–60%) - advise patient of this possibility
• No malignant potential - no systemic surveillance required