[Methods for postoperative evaluation of complete excision of the mesorectum]

This study aimed at a more objective evaluation of the specimen after total mesorectal excision [14]. For this reason, a method yielding a simple stained preparation of the totally excised mesorectum was developed. By postoperative injection of 10 ml of an ink solution into the A. rectalis superior of 15 specimens, the arterial mesorectal vascular tree was filled. All specimens had been collected by means of total mesorectal excision. In two specimens, in wich the mesorectal sheath fascia had been injured due to the surgical manipulation, we observed the leakage of ink from the mesorectum even during the injection. In three further specimens, some ink leakage in the form of dots occurred from small opened arterioles after the injection was performed. No ink leakage was observed in the remaining specimens. Prior to the ink injection, thirteen specimens were macroscopically tested and found intact. Three of the fifteen specimens exhibited minor lesions of the mesorectum that would not have been detected macroscopically without ink tagging. The comparison of the findings provided by the surgeon with the histopathological evaluation showed that those specimens in which no ink leakage occurred had an unimpaired mesorectal sheath fascia. These specimens coorespond to the complete excision of the mesorectum and the removal of the tumor in a cancer-sealed package as long as the circumferential rim of the specimen has not been infiltrated by the tumor.