ACCURACY OF IMAGE GUIDED PERCUTANEOUS NEEDLE BIOPSY COMPARED TO PERCUTANEOUS NEEDLE BIOPSY WITHOUT IMAGE GUIDANCE IN DIAGNOSIS OF SOFT TISSUE TUMOURS.

The aim of this study was to compare the accuracy of image guided (ultrasound or CT) percutaneous needle biopsy to percutaneous needle biopsy without image guidance in diagnosis of soft tissue tumours. Eighty-eight consecutive patients with soft tissue lesion who were referred to the soft tissue tumour unit underwent percutaneous needle biopsies of their lesion either with image guidance or without. Sixty-one out of these 88 patients subsequently underwent excision of their lesion and the excised specimen was then subjected to histological examination. The accuracy of image guided percutaneous needle biopsy and percutaneous needle biopsy without image was then calculated by comparing the histological results of the needle biopsy to that of excision biopsy. The diagnosis accuracy of image guided percutaneous needle biopsy was 92% (34 out 37) compared to 79% (22 out of 28) for percutaneous needle biopsy without image. In 3 out of the 28 patients who had percutaneous needle biopsy without image guidance, there was insufficient material obtained from the needle biopsy to allow a histological diagnosis. This was not the case with any of the patients who had image guided percutaneous needle biopsy. Conclusion: Using image guidance, either USS or CT scan, improves the diagnostic accuracy of percutaneous needle biopsy and should be the gold standard technique in management of soft tissue tumours. However, if the lesion is palpable and not mobile, the accuracy of percutaneous needle biopsy without image guidance can be up to 79%.