The role of core needle biopsy in the diagnosis of suspected soft tissue tumours

Background: Controversy surrounds the biopsy method of choice for the histological diagnosis of soft tissue sarcoma. The objective of this study was to evaluate the diagnostic accuracy of core needle biopsy (CNB) in patients referred with the suspicion of a soft tissue sarcoma.

Methodology: Previously undiagnosed patients (n = 530) with a suspected soft tissue tumour (STT) who underwent CNB at initial presentation were identified. Specific end-points were the ability to differentiate benign from malignant tumours, soft tissue from non-STT, and for sarcomas to define subtype and grade.

Results: Of the 530 patients, 426 patients (80.4%) with soft tissue tumours were identified, of which 225 (52.8%) were malignant and 201 (47.2%) benign. In the remaining 104 patients, tumours masquerading as STT were diagnosed. CNB could differentiate soft tissue sarcomas from benign soft tissue tumours with an accuracy of 97.6%. High grade were differentiated from low grade sarcomas with an accuracy of 86.3%. Tumour subtype was accurately assigned in 89.5% of benign tumours and 88.0% of sarcomas.

Conclusion: CNB is simple, safe and can accurately diagnose benign and malignant soft tissue tumours. It can reliably identify other tumours masquerading as sarcoma. CNB should be the method of choice to obtain a histological diagnosis in suspected STT.