Aims
1. Provide representative sample
2. Not compromise definitive treatment
Biopsy
Options
Open
- incisional biopsy
- excisional biopsy
Image guided
- fine needle aspirate
- core needle biopsy
Open biopsy
- larger sample of tissue
- larger tract to later excise
- higher risk of complication such as infection / hematoma
Results
Dirks et al World J Surg Oncol 2023
- incisional biopsy of 332 malignant musculoskeletal tumours
- sensitivity 100%, specificity 97.6%
Tsukushi et al Arch Orthop Trauma Surg 2010
- CT guided needle biopsy in 207 patients with musculoskeletal lesions
- diagnostic accuracy 90%
- meta-analysis of 2680 patients with soft tissue sarcoma
- Incisional: sensitivity 96%, specificity 100%
- Core needle: sensitivity 97%, specificity 99%
- complication RR = 0.14 favoring needle
Performed by treating surgeon at treatment centre
Results
- 329 sarcoma patients
- complication rate > 5 times higher when performed by other surgeon / other hospital
- 60% major error in diagnosis
- 20% treatment compromised by biopsy
- 4.5% had unnecessary amputation due to poor biopsy
- musculoskeletal tumour society
- follow-up study from 1982 (n=597)
- rate of diagnostic error 17.8%
- problems with biopsy causing change in treatment to more difficult or complex procedure 19.3%
- change in outcome attributed to biopsy 10.1%
- 18 patients had unnecessary amputation
Open Biopsy Technique
Pre-operative
Tumour staging first / all imaging obtained / images reviewed with experienced MSK radiologist
Treating surgeon does biopsy at treating hospital
- discussed with tumour centre if not possible
Ensure expert pathological facilities
- experienced MSK pathologist
- frozen section available
No pre-op antibiotics / infection always in differential diagnosis
Tourniquet
- no exsanguination
- release before closure and obtain hemostasis
Intra-operative
1. Approach
- plan with future OT in mind
- all aspects of biopsy tract must be excised later
- incision must be incorporated in definitive surgery
- violate one compartment only / trans-muscular
- incision is longitudinal, no undermining skin edges
- don't expose NV structures
- meticulous hemostasis
2. Biopsy
- round cortical windows / decreased stress-risers
- swab taken / tissue for M/C/S
- tissue for FFS / histology
- no closure until discussion with pathologist on phone
- ensure they have enough to make a definitive diagnosis / cell line / grade
3. Closure
- plug bone windows with PMMA / minimises tumour spread
- achieve hemostasis
- closure in layers
- drain exit site in line with and through wound
- subcuticular suture to skin
- firm dressing
- immobilise
Post operative
Very careful post op
- pathological fracture can change outcome
Team approach
- pathologist / radiologist / oncologists / radiation oncologist
- all results are reviewed to ensure correct diagnosis and management