Port Wound Tumors

Abstract

Port site tumor recurrences were the single most controversial issue regarding minimally invasive methods in the 1990’s. Reports of these wound tumors, predominantly in patients with colorectal cancer, significantly slowed adoption rates of laparoscopic methods in the cancer setting. The reluctance of the vast majority of surgeons worldwide to adopt laparoscopic methods combined with the tenacity and determination of the proponents to carry out the randomized cancer studies led to a wholly unique situation in the general surgery world: a new surgical method was actually properly vetted prior to widespread acceptance and implementation. While the world waited for the intermediate term human cancer results a number of surgical groups designed and performed basic science studies that sought to explain and understand the phenomenon of port wound tumors. Finding an appropriate and realistic model proved difficult. Tumor cell suspension models were utilized, often with very large tumor cell inoculums; most of these studies suggested that CO2 pneumoperitoneum increased the size and number of intraabdominal recurrences and wound tumors. Other investigators utilized solid tumor models which sometimes assessed pneumoperitoneum conditions not comparable to the human situation; the great majority of these studies also suggested that the CO2 pnemoperitoneum was a large risk factor. However, there were some animal studies carried out which used models that were more comparable to the human situation. The results of these studies supported the concept that surgical traumatization of the tumor during surgery was the most likely cause of port wound tumors and that the CO2 pneumoperitoneum itself did not appear to increase the incidence. Publication of the multi-center study results during the last 2-3 years has largely put an end to the discussion regarding wound tumors. These studies suggest that the incidence of wound tumors and the long term cancer outcomes are no different for open and closed methods. Since these reports, the adoption rates of minimally invasive methods have greatly increased and will continue to do so. The general consensus, in 2007, is that poor technique, traumatization of the tumor, and primary tumors that spontaneously shed viable tumor cells are the most likely cause of these distressing problem. Regardless, the great majority of surgeons utilize methods to decrease the chances of port tumors: anchoring of ports, frequent and thorough irrigation (+/− tumoricidal agents), avoidance of tumor handling (no touch methods), use of wound protector or bag, etc, etc.