Aims
1 Provide representative sample
2 Not compromise definitive Treatment
Principles
- Done to confirm diagnosis
- Last step in evaluation
- After imaging to stage
- Performed by treating surgeon
Open vs Closed
Advantages of Open
- More tissue
- Lower sample error
Advantages of Needle Biopsy
- Less expensive
- Less risky
- Smaller field to excise later
Disadvantages of Needle Biopsy
- Accuracy 70-84% vs 96% with Open
Indications for Needle Biopsy
- 1 Homogenous tissue expected
- Myeloma
- 2 Treatment Not changed by subtle differences
- Soft Tissue Sarcoma
- 3 Diagnosis rel certain
- Mets
- 4 Access difficult
- Spine, Pelvis
- 5 Expert histologist available
Incisional vs Excisional
- Only for ST lesions
- Excisional if < 1.5cm
- e.g. Ganglion, Small Lipoma
- Incisonal if > 1.5cm
- Excisional has inc risk of contaminated field & NV contamination
Preoperatively
- Tumour Staging Ix 1st
- Treatment Surgeon does Bx
- Ensure expert pathol facilities
- No preop AB
- In case infection
- Tourniquet
- No exsanguination
- Release before closure
Intraoperatively
Approach
- Plan with future OT in mind
- Violate min no of compartments
- Increased chance limbsparing
- Longit incision
- Permits excision enbloc
- No flaps
- °between muscles to dec no of muscles sacrificed on resection
- Don’t expose NV structures
- Else have to sacrifice
Biopsy
- Round bone windows
- Decreased stressrisers
- Include softtissue component
- Avoid periosteal r’n as confusing
- Ensure rep sample with FFS
- Tissue for M/C/S
Closure
- Plug bone windows with PMMA
- Min tumour spread
- Achieve haemostasis
- Drain exit site in line with & close to wound
- Firm dressing
- Immobilise
Histology
4 types of investigations
- 1 Light microscopy
- 2 Immunoperoxidase stains
- 3 Electron microscopy
- 4 Cytogenetics