The management of non-diagnostic soft tissue tumour biopsies using a multi-disciplinary team approach: A 10-year retrospective review at a specialist sarcoma unit.

Non-Diagnostic (ND) biopsies are occasionally encountered during the investigation of soft tissue sarcoma. We performed a retrospective review of all ND soft tissue biopsies discussed at our regional Multi-Disciplinary Team (MDT) meeting between 2004 & 2014 with the aim of establishing the incidence of ND biopsies, identifying predictive factors for repeat biopsies and evaluating the effectiveness of MDT decisions. We identified 80 ND out of 3233 biopsies. Diagnostic Yield (DY) was 97.5%, 76.0% and 77.8% for the first, second and third successive biopsy respectively. With an MDT approach utilising radiological and clinical information, the diagnostic success rate achieved was 98.5%, 82.0% and 77.8% for the first, second and third biopsies respectively. Malignant tumours (sarcoma & carcinoma) were 19 times more likely to undergo an increasing number of biopsies compared to benign lesions (p < 0.01), while repeat biopsies were less useful for suspected benign lesion. Although a repeat biopsy was only performed in 63% of cases, there were no patients originally diagnosed with a benign lesion that re-presented with the same lesion subsequently being malignant throughout the study period. Our study shows that a specialist MDT approach leads to high diagnostic rates and is a safe and effective method of preventing unnecessary, repeat biopsies where the initial biopsy is ND.