Introduction: The Musculoskeletal Tumour Society recommends that patients with musculoskeletal tumours are treated in specialist centres. Core needle biopsy is an effective method of obtaining tissue diagnosis but a dilemma arises when the material is non-diagnostic. Our aim was to evaluate the management of non-diagnostic biopsies.

Method: We retrospectively reviewed all core needle biopsies performed between 2003 and 2009 in our regional centre. Non-diagnostic biopsies were identified and management reviewed.

Results: 4,520 core needle-biopsies were performed of which 120 (2.6%) were non-diagnostic. Of these 85 (70%) were treated definitively on the basis of existing imaging, 8 (7%) required further imaging before treatment and 27 (23%) had a repeat biopsy.

Of the 27 repeat biopsies a positive histological diagnosis was obtained in 22 patients. The remaining 5 were again non-diagnostic giving a total of 98 patients being treated definitively without a tissue diagnosis.

Of these 98 cases, 39 (40%) were treated non-operatively, 37 (38%) had curettage and 22 (22%) underwent wide excision.

In the curettage group 33 out of 37 patients had a benign tumour on final histology. Four patients turned out to have intermediate/high grade tumours and subsequently underwent wide excision.

In the wide excision group, 17 out of 22 patients had an intermediate/high grade tumour on final histology. Five patients underwent an unnecessarily wide excision of a benign lesion.

None of the patients treated non-operatively turned out to have a tumour.

Conclusion: After non-diagnostic core-needle biopsy, the patient can safely be managed without tissue diagnosis, with low error rate, provided they have been subjected to a multidisciplinary discussion.