[Technique and tactics of biopsy including puncture]

The biopsy is the key for the exact diagnosis of bone and soft tissue sarcomas. However the biopsy implicates risks that eventually may significantly interfere with the prognosis. The steps of the biopsy can be differentiated in tactical and technical aspects. Tactical aspects include laboratory examinations (e.g. blood count, immunological, chemical tests) in order to establish the prebiopsy differential diagnosis, basic imaging procedures (bone scan, magnetic resonance imaging) and to discuss with the pathologist questions as which region of the tumor might be most informative, how should the material be preserved and whether a frozen section might be useful and allow for initiation of therapy as early as possible. Furthermore the site of the biopsy has to be carefully chosen, the compartments that need being passed through or opened up during biopsy must be considered. The technical aspects refer to the approach and tissue handling during the biopsy itself. Fine needle aspiration allows only for a cytologic, core biopsies for a histologic examination (however only of a small sample), while the open biopsy provides more material for more analyses. Any biopsy (open biopsy as well as percutaneous puncture) contaminates the path with tumor cells and increases the risk of systemic seeding. In order to keep these risks as small as possible the most careful technique and tissue handling is mandatory. The biopsy path has to be completely ('en bloc') resected later for local tumor control.