Background
The primary aim of the present retrospective study was to evaluate the feasibility and efficacy of laparoscopic prophylactic
oophorectomy plus N3 lymph node dissection for patients with rectosigmoid cancer. The secondary aim was to explore the clinicopathologic
features of ovarian micrometastasis from rectosigmoid cancer.
Methods
We performed 244 laparoscopic resections of rectosigmoid cancer in women during a 6-year period. In them, 34 patients (13.9%)
were subjected to prophylactic oophorectomy plus N3 lymphadenectomy in addition to the standard anterior or low anterior resection
of rectosigmoid cancer, because the patients presented with ovarian cystic lesions, tethering of the ovary to the primary
rectosigmoid tumor, and/or pelvic ascites accumulation, which were postulated as the indicative findings for the synchronous
ovarian micrometastasis. The surgical procedures are detailed in the attached video. The surgical outcomes were compared between
patients with (n = 34) and without (n = 210) these two additional procedures. In analyzing the clinicopathologic features
of ovarian micrometastasis, we included both cases of laparoscopic (n = 34) and traditional open surgery (n = 30), whose prophylactic
oophorectomy was performed by the same surgical indications.
Results
Although the operation time was significantly longer (264.2 ± 24.5 vs. 192.5 ± 24.2 minutes, P < .0001) in patients with prophylactic oophorectomy and N3 lymphadenectomy, there was no significant difference between patients
with and without the two additional procedures in blood loss, wound length, postoperative complications, diverting ileostomy,
and mortality. Although flatus passage, hospitalization, postoperative pain, and return to partial activity were statistically
different between the study groups, they were deemed clinically unimportant because the difference of mean was very small.
Foley removal was delayed in patients with N3 lymphadenectomy by 2 days. With respect to surgical efficacy, we found that
patients undergoing the two additional procedures could collect significantly more lymph nodes (22.0 ± 4.0 vs. 14.4 ± 2.4,
P < .0001) for pathologic staging and facilitated upstaging of nodal status in three patients (8.8%). Patients undergoing prophylactic
oophorectomy plus N3 lymphadenectomy could achieve good oncologic outcome, with the estimated 5-year survival rate of 62.5%
and 69.2% in patients with and without ovarian micrometastasis, respectively. Clinicopathologically, patients with ovarian
micrometastasis (n = 15) tended to have vascular invasion of tumor cells, as compared with those without (n = 49). However,
ovarian micrometastasis was not related to menstrual status of patients, tumor location, tumor size, morphology, differentiation,
mucin production, T stage, nodal invasion, and level of carcinoembryonic antigen.