Piya Kiatisevi1,  Torsten Nielsen2,  Malcolm Hayes2,  Peter L Munk3, Amy E LaFrance4, Paul W Clarkson4, 

Bassam A Masri4  

1Orthopaedic Oncology Lerdsin Hospital, Institute of Orthopaedics, Lerdsin Hospital, Bangkok, Thailand2Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada

3Department of Radiology, University of British Columbia, Vancouver, BC, Canada 4Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada

Saturday, November 15, 2008

Background

Open biopsy is the historical gold standard for diagnosing bone and soft-tissue lesions

Highly accurate 16% complication rate 12% treatment altered 1.2% unnecessary amputation

Mankin et al., J Bone Joint Surg Am. 1996;78(5):656-663

Core Needle Biopsy (CNB)

Increasingly accepted for the diagnosis of bone and soft-tissue lesions

Reduced morbidity, time and cost Fewer complications

Concerns remain regarding accuracy of CNB

Objectives

To assess and compare : Core Needle Biopsy (CNB) Open Biopsy (OB) Fine Needle Aspiration (FNA)

Diagnostic rate

Accuracy for Distinguishing benign vs. malignant Histological diagnosis Distinguishing low vs. high grade sarcoma

Materials and Methods

Prospectively collected database 286 biopsies in 282 patients 2004-2007 165 males, 117 females Mean age 51 yrs (range 16-92 yrs)

Biopsy compared to final pathology

Included biopsies performed prior to referral but slides were re-reviewed by an experienced MSK pathologist

Our Practice

Patients are assessed in MSK surgical clinic Site for CNB is marked with indelible marker Image-guided biopsy performed by radiologist

within pre-marked biopsy site 10mm biopsy incision so site is identifiable for

definitive resection

Our Practice

If core needle biopsy is non-diagnostic, then proceed with open biopsy

Biopsy track excised en bloc with tumour during definitive resection

229 CNB

32 OB

25 FNA

286 biopsies

Biopsy Types

Tumour type Bone Soft-tissue Total

Benign tumours 29 90 119

Sarcomas 18 117 135

Non-sarcoma malignancies

8 12 20

Tumour-like lesions 1 11 12

Total 56 230 286

Types of Lesions

ResultsResults

Diagnostic Rate

92% 100% 72%

Non-diagnostic SpecimensNon-diagnostic Specimens

Benign Malignant

Bone (B) 6 4

Soft-tissue (ST)

7 1

CNB (18/229 = 8%)

Benign Malignant

Bone (B) 0 0

Soft-tissue (ST)

6 1

FNA (7/25 = 28%)

Accuracy for Distinguishing Benign vs. Malignant

Accuracy 89% 97% 68%

Benign (at biopsy) Malignant (final pathology)

CNB (n=229)6 Benign lipomatous tumour Well-differentiated liposarcoma

(ST)

1 Fracture healing Adenocarcinoma metastasis (B)

OB (n=32)1 Leiomyoma Leiomyosarcoma (ST)

FNA (n=25)1 Mature fat Well-differentiated liposarcoma (ST)

Incorrect Diagnosis of Benign vs. Malignant

Malignant (at biopsy) Benign (final pathology)

CNB (n=229)1 Lymphoma of ilium Osteomyelitis (B)

OB (n=32)0

FNA (n=25)0

Incorrect Diagnosis of Benign vs. Malignant

Accuracy for Histological Subtype

Accuracy 70% 81% 40%

Type Bone Soft-tissue Total

Benign tumors 29 90 119

Sarcoma 18 117 135

Non-sarcoma malignancy

8 12 20

Tumour-like lesions 1 11 12

Total 56 230 286

Accuracy for Distinguishing Low vs. High Grade Sarcoma

Accuracy for Distinguishing Low vs. High Grade Sarcoma

Accuracy 90% 96% 72%

Low grade (at biopsy) High grade (final pathology)CNB (n=92)

3

OB (n=24)

0

FNA (n=10)

2

High grade (at biopsy) Low grade (final pathology)None

1 Osteosarcoma (B)1 Liposarcoma (ST)1 Ossifying fibromyxoid tumour (ST)

1 De-diff. Chondrosarcoma (B)1 Myofibroblastic sarcoma (ST)

Incorrect Diagnosis of Low vs. High Grade Sarcoma

Type nDiagnostic

Rate

Accuracy for benign vs. malignant

Accuracy for histological diagnosis

Accuracy for low vs. high

grade sarcoma

CNB 229 92% 203/229 (89%) 161/229 (70%) 89/99 (90%)

OB 32 100% 31/32 (97%) 26/32 (81%) 24/25 (96%)

FNA 25 72% 17/25 (68%) 10/25 (40%) 8/11 (72%)

Discussion

Discussion

Perform CNB with care on fatty lesions

Conclusion

Core needle biopsy is accurate for determining: Benign vs. malignant Histological subtype Low vs. high grade for sarcoma

Advantages of core needle biopsy Fewer complications Reduced cost of treatment High diagnostic accuracy

Recommendations

CNB be used routinely for diagnosis, whenever possible

Open biopsy reserved for use when CNB is non-diagnostic

Given its high inaccuracy, FNA is not indicated for diagnosing musculoskeletal lesions in the extremities

Thank you

Orthopaedic Oncology Lerdsin Hospital, Bangkok, Thailand

The University of British Columbia, Vancouver, BC, Canada

TypeCNB (N= 229)

OB (N=32)

FNA (N=25)

Benign bone tumours 5 - -

Malignant bone tumours 2 - -

Benign soft-tissue tumours 5 - 6

Malignant soft-tissue tumours 1 - 1

Carcinoma and myeloma 2 - -

Tumour-like lesions 3 - -

Total 18 - 7

Non-diagnostic rate 8% 0% 28%

Diagnostic rate 92% 100% 72%

Non-diagnostic Specimens