Diagnostic outcome of two different CT-guided fine needle biopsy procedures

Background: CT-guided fine needle bioptic procedures (CTFNP) are characterised by low invasiveness, precise sample collection, a high diagnostic efficiency and support a rapid diagnostic process. A number of different fine needles and bioptic procedures are mainly used for tumour diagnostics today. The aim of the present study was to characterise the most important technical issues of fine needle bioptic procedures. In addition, we directly compared the diagnostic outcome and reliability of the most commonly used Rotex Screw Needle - (RSN) and Yale Needle - (YN) bioptic procedure. Methods: In an experimental part of the study, using pig spleen, we measured the maximum number of sampled cells using different needles and aspiration volumes. For the clinical questions we analysed all consecutive 340 patients in which CTFNP were performed between 1/97-12/05 in the hospital Grosshansdorf. We evaluated the number of adverse events based on all clinical available information and compared the cytological findings with the respective final diagnosis (confirmed: clinically n = 192, histologically n = 148). Results: Using the YN with at least some negative pressure we found a proportional increase of cell and tissue recovery with increasing number of needle movements. A sensitivity of 78% and a specificity 98% indicate a high diagnostic outcome of CTFNP. We found no statistical significant difference in terms of sensitivity (80 vs. 68%) as well as complication rates (5.9 vs. 4.4%) between RSN or YN. Conclusion: As fine needle basically works like a cutting instrument, it is possible to raise the cell/tissue recovery. Keeping this in mind we found a high diagnostic outcome of CTFNP, which was largely independent of needle type and bioptic technique, and comparable with other conventional bioptic procedures.