Introduction Purpose of the biopsy is to confirm a suspected diagnosis The biopsy is not a substitute for a thorough history, physical exam, and laboratory investigation prerequisites for a biopsy CBC, platelets, coagulation studies cross-sectional imaging to evaluate local anatomy treatment center performing biopsy must be capable of proper diagnosis and treatment Indications for Biopsy Indications aggressive bone or soft tissue lesions soft tissue lesions larger than 5cm, deep to fascia, or overlying bone/neurovascular structures unclear diagnosis in a symptomatic patient solitary bone lesions in a patient with history of carcinoma When a biopsy is not indicated asymptomatic latent bone lesions or a symptomatic active bone lesions which appear entirely benign on imaging don't necessarily need a biopsy soft tissue lesion which are completely benign on MRI don't necessarily need a biopsy (e.g. lipoma, hemangioma) Types of Biopsy Fine Needle Aspiration (FNA) provides cytologic (cellular) specimen frequently used for carcinoma not typically used for sarcoma Core biopsy (Tru-cut) allow for tumor structural examination can evaluate both the cytologic and stromal elements of the tumor frequently used for soft tissue sarcoma 85-95% accuracy in diagnosis Incisional biopsy small surgical incision carefully placed to access tumor without contamination of critical structures Excisional biopsy select indications: small, superficial soft tissue masses Principles of the Open Incisional Biopsy Incision use longitudinal incision in the extremities allows for extension of the incision for definitive management Approach do not expose neurovascular structures all tissue exposed during the biopsy is considered contaminated with tumor maintain meticulous hemostasis post-operative hematomas are considered contaminated with tumor release tourniquet prior to wound closure Biopsy perform through the involved compartment of the tumor for bone lesions with a soft tissue mass, it is ok to perform the biopsy using the soft tissue mass Closure if using a drain, bring drain out of the skin in line with surgical incision allows drain site to be removed with definitive surgical extensile incision