DISCUSSION
This is the first report for the surgical procedures for early ovarian cancer as far as we know. The objective of this study is to know the surgical effort to remove all suspicious metastatic lesions and the pathological outcomes in the surgical management of early epithelial ovarian cancer. Resection of the rectosigmoid colon with accompanying pelvic peritonectomy was required in approximately one-third patients with early epithelial ovarian cancer for complete removal of all suspicious metastatic lesions.
In advanced ovarian cancer, the benefits of resection of the rectosigmoid colon as part of cytoreductive surgery was reported by several investigators.11-14 The rate of leakage and fistula was 1.7-3.1% and 0-3.3% after resection of the rectosigmoid colon and primary anastomosis in patients with advanced ovarian cancer.11, 13, 14 In the current study, no leakage and fistula were identified.
Resection of the rectosigmoid colon and primary anastomosis could be easily and safely performed in early ovarian cancer compared to advanced ovarian cancer. First, tension-free anastomosis was more easily performed in early ovarian cancer patients. Because cancer invasion of the colon was limited to the pelvis and the descending colon was free of tumour which permits easier taking off the proximal colon for anastomosis. Second, a more favoruable environment for postoperative recovery after complete cytoreduction was allowed in patients with early ovarian cancer. More than half of the patients with advanced ovarian cancer had still peritoneal seeding after cytoreductive surgery in our previous report.11 In the current study, complete cytoreduction was possible in all patients with early ovarian cancer. Third, adjuvant chemotherapy was skipped or minimized in patients with early ovarian cancer compared to advanced ovarian cancer.
In the current study, endometriosis is the second common cause to perform resection of the rectosigmoid colon in patients with early ovarian cancer. It is not surprising because more than half of the patient with stage I ovarian cancer has endometriosis.1 In the surgical field, the differentiation of endometriosis from metastatic ovarian cancer is difficult. Many epidemiologic, histologic, and molecular studies revealed that endometriosis is a precursor lesion of ovarian cancer.15-17 Endometriosis at the rectum could cause pain on defecation and the most effective surgical treatment is full-thickness excision of the anterior rectal wall or segmental resection of the rectum.8 Therefore, we can raise the potential benefit of resection of the rectosigmoid colon in early ovarian cancer patients.
Special consideration was required to minimize the resection of cancer or endometriosis free rectum. We did not split between the rectum and uterus to avoid possible disrupt and seeding of cancer during surgical procedures. If there is adhesion between the rectum and uterus, we remove them en bloc. Four patients who underwent resection of the rectosigmoid colon had neither cancer nor endometriosis. Two patients had endometriosis-related adhesion between the rectum and uterus because they had no previous operation history and revealed peri-adnexal endometriosis. And another two patients had a previous history of abdominal operation.
Selection bias and other confounders found in retrospective studies were also possibilities in this study, and we made an effort to minimize the selection bias and confounders as much as possible. The incidence of co-existing endometriosis was obtained from a retrospective review. Therefore, the incidence of endometriosis may increase if more sections to identify endometriosis are obtained from the tumours in a prospective setting.
In conclusion, resection of the rectosigmoid colon with adjacent pelvic peritonectomy is required in 28.8% of the patients with early ovarian cancer for complete removal of all suspicious metastatic lesions in the pelvis. Cancer invasion, endometriosis, and fibrosis and/or adhesion are the cause to perform resection of the rectosigmoid colon in such patients.
Contribution to authorship :
Conception: MC Lim, SY Park
Planning: MC Lim
Carrying out, analysing and writing up of the work: Myong Cheol Lim, Sang-Soo Seo, Sokbom Kang, Sun Ho Kim, Chong Woo Yoo, Sang-Yoon Park