Needle guided biopsy of a suspected musculoskeletal malignancy has become increasingly popular as an effective modality for diagnosis. Biopsy performed in a safe manner should be performed in a centre which is also capable of performing the definitive management of such conditions. Our aim was to determine accuracy and success rates of the image guided biopsies performed by our service. A retrospective review of the Bone and Soft Tissue Sarcoma service database was performed to identify all patients who underwent diagnostic biopsy and to identify the results of such investigations. A biopsy was deemed successful if a sample of the target lesion was sampled at the time of biopsy. The successful biopsies were then classified as diagnostic or non-diagnostic if the diagnosis could be reached from the sampled tissue.Introduction
Methods
Although most peripheral nerve sheath tumours are benign, some are malignant. The management of malignant tumours usually involves wide excision and is facilitated by knowledge of the diagnosis prior to operation. Imaging modalities, including MRI, give anatomical information but do not distinguish between benign and malignant nerve tumours. We therefore introduced the use of ultrasound guided needle biopsy for suspected nerve tumours to our unit in 2004. Prior to this, excision biopsy was carried out in all cases. We aimed to review our experience with needle biopsy and determine whether it has an effective role in the management of peripheral nerve tumours. All patients who had a needle biopsy for suspected peripheral nerve tumours from January 2004 to December 2011 were identified from our tumour database and clinical notes reviewed. In all cases, biopsy was carried out under ultrasound guidance with local anaesthesia to obtain a 1mm core of tissue. From 25 patients reviewed, 21 (84%) had a successful biopsy. In 3 cases the biopsy was unable to be completed due to pain and in 1 patient insufficient tumour tissue was obtained. 1 patient had a temporary radial nerve palsy following needle biopsy which recovered fully. In biopsies that were successful, 19 (90%) showed a benign peripheral nerve tumour. Following diagnosis of a benign lesion, only 2 patients required to have surgical excision of the tumour due to pain. The remainder were managed non-operatively. In the 2 cases of malignant tumours detected by biopsy, a successful wide surgical excision was performed. Ultrasound guided core needle biopsy appears safe and gives a tissue diagnosis in most cases of suspected peripheral nerve tumours. In malignant cases it facilitates surgical planning, while most benign tumours could be managed non-operatively, therefore avoiding potential complications of nerve surgery.
Bizarre parosteal osteochondromatous proliferation (BPOP) is a benign lesion of bone originally described by Nora et al in 1983. To date there are no UK-based case series in the literature. Here we present the Scottish Bone Tumour Registry (SBTR) experience of this rare lesion. A retrospective analysis of SBTR records was performed. Histological specimens were re-examined by a consultant musculoskeletal oncology pathologist. Radiographs were re-reported by a consultant musculoskeletal radiologist. From 1983-2009, 13 cases were identified; 6 male, 7 female. Age ranged from 13-65. All patients presented with localised swelling. Pain was present in 5 and trauma in 2. 9 lesions affected the hand, 3 the foot, and 1 the tibial tuberosity. 12 lesions were excised and 1 curetted. There were 7 recurrences of which 6 were excised. 1 patients' recurrence was not treated. 1 lesion recurred a second time. This was excised. There were no metastases. Radiographs typically showed densely mineralised lesions contiguous with an uninvolved cortex. Cortical breakthrough was present in 1 case and scalloping in another. Histology characteristically showed hypercellular cartilage with pleomorphism and calcification/ossification without atypia; bone undergoing maturation; and a spindle-cell stroma. SBTR records indicate that BPOP is a rare lesion with no sex predilection that affects patients over a wide age range. Minor antecedent trauma was present in only 2 cases. In agreement with Nora et al. we feel that trauma is unlikely to represent an aetiological factor. Recurrence was over 50% in this series. Although this is similar to that found in other reports, it may indicate that more extensive resection is required for this aggressive lesion. Finally, although radiological/histological findings are often bizarre there have been no reported metastases and so it is important that BPOP is not mistaken for, or treated as, a malignant process such as chondrosarcoma.