ABSTRACT
Increasingly, many lesions are diagnosed on the basis of percutaneous biopsies guided by imaging such as computed tomography (CT). Ideally, these should be submitted fresh to the pathology department to allow maximum information to be derived from what may be a small amount of tissue. Often, touch preparations allow an initial assessment to be made and help select additional investigations; seeing a small round blue cell tumor, for example, would suggest that a core or part of a core should be sent for cytogenetic analysis, unfixed in tissue transport medium. The increasing availability of molecular biological methods capable of using paraffin-embedded sections may in time supplant classic karyotyping.
