Background: Lymphadenectomy is a surgical technique for staging and treating cancer. Laparoscopic lymphadenectomy for obese patients is challenging. Laparoscopic ultrasound-assisted liposuction (UAL) has been successful in porcine models. The current study aimed to evaluate whether UAL facilitates pelvic laparoscopic lymphadenectomy in obese subjects.
Methods: The UAL technique was evaluated in two human cadavers and in six obese Ossabaw pigs. Both a standard and a prototype ultrasonic probe with a wider contact surface were tested. Pelvic lymphadenectomy comparing UAL with standard monopolar cautery was performed using obese Ossabaw pigs. The animals were survived for 2 weeks. Descriptive data regarding intra- and postoperative outcomes were recorded, including histologic analysis of dissected tissue after 2 weeks. Cytologic analysis of aspirated fluid coming from UAL also was recorded.
Results: The UAL procedure was safely performed for all the cadavers and animals. Lymph node exposure and clean exposure of surrounding structures were dramatic compared with monopolar assisted dissection. One animal was excluded from further analysis due to ultrasonic device malfunction (a broken footswitch cord). In general, UAL notably debulks adipose tissue with dramatic field exposure. Postoperative adhesions were present in all animals undergoing either monopolar or UAL dissection. Histology showed areas of foreign body reaction from mild to severe, with no predominance of either extreme seen with monopolar or UAL dissection. Cytologic analysis of collected pooled oil emulsion did not contain lymph node tissue.
Conclusion: The UAL approach permits pelvic lymphadenectomy in the obese animal and cadaver model, with excellent exposure of lymph nodes and surrounding pelvic anatomy. The use of a new ultrasonic prototype probe with a wider contact surface allowed dissection with less mechanical and thermal penetration of tissue. Further studies are needed to assess oncologic safety (cancer cell dissemination), postoperative healing, and adhesion formation.