A study of the incidence of implantation cyst at anastomotic sites after low anterior resection of the rectum with the double stapling technique.

BACKGROUND

The incidence of implantation cyst occurring at sites of anastomosis after low anterior resection of the rectum were studied in two different periods depending on the type of surgical devices used to close the rectal stump.

SUBJECTS

The study included 361 patients undergoing the surgery during the first 8-year period between 1996 and 2003 and 87 patients undergoing the surgery during the second 3-year period between 2004 and 2006.

RESULTS

Implantation cysts were found in nine (2.5%) of the patients undergoing the surgery during the first period and one of them also had local recurrence. Implantation cysts occurred 9 to 31 months postoperatively (mean, 17.1 +/- 6.9 months). Clinical symptoms were noted in one patient and treatment of the cysts, including local recurrence, was given to two patients. Anastomosis of the distal rectum was performed with the Roticulator or the Access 55 in all patients. Although implantation cysts were found in any patient undergoing surgery during the second period, no statistically significant difference was recognized (p = 0.217). Anastomosis of the distal rectum was performed with the TX30 in all patients.

CONCLUSION

The pathogenesis of implantation cysts may be explained by the production of mucus when the mucosal epithelium of the colon is caught under the submucosa, forming a cyst after closure of the rectal stump, and the difference in the incidence rates of implantation cyst was presumably due to the characteristics of the device used and progress of the operative procedure.