DOES THE ULTRASONICALLY ACTIVATED SCALPEL RELEASE VIABLE AIRBORNE CANCER-CELLS

Background: Viable cancer cells may implant at distant sites and cause tumor recurrence, One possible mechanism is the inadvertent exfoliati on of viable tumor cells during dissection. The ultrasonically activat ed scalpel (UAS) uses ultrasonic energy to disrupt tissues by cavitati on and produces a dense cloud of cellular debris that may contain viab le cells. This study aimed to investigate the viability of airborne ce lls released during cancer dissection using the UAS and electrosurgery . Methods: Flank tumors (n = 8) measuring 1 cm(3) were induced in male WAG rats by subcutaneous injection of 2 x 10(6) CC531s colon cancer c ells. Dissection was performed in cutting mode using the maximum power output of the respective devices. Electrosurgery was performed using a standard monopolar electrosurgical unit and a needle probe, and ultr asonic dissection was performed with the Harmonic Scalpel(TM) utilisin g the open surgical handset and the hooked spatula tip. The smoke plum e was aspirated by a vacuum pump and bubbled under Hank's balanced sal t solution to trap particulate matter. The viability of the cellular m aterial was blindly assessed with the trypan blue test and by in vitro culture. The morphology of the cellular debris was studied by examina tion of cytospin preparations. Results: Large quantities of cellular d ebris was trapped in the plume from both devices. However, no viable c ells were isolated, nor did in vitro cell growth occur with either dev ice. Examination of the debris from the UAS demonstrated a characteris tic mixture of amorphous forms and very few morphologically intact cel ls. The cauterized tumor produced charred cells and tissue fragments. Conclusions: In conclusion, this study demonstrates that viable airbor ne cancer cells are not released after tumor ablation with the UAS or electrosurgery.