Incidence of metastasis in the circumflex iliac nodes distal to the external iliac nodes in ovarian cancer

ObjectiveThe circumflex iliac nodes distal to the external iliac nodes (CINDEINs) are included in the regional lymph nodes that are commonly dissected during systematic lymphadenectomy for ovarian cancer. Because in recent years CINDEIN dissection has been reported as a significant risk factor for postoperative lower limb lymphedema, we investigated the validity of omitting the CINDEIN dissection by evaluating the distribution pattern of positive lymph nodes in ovarian cancer, in order to improve postoperative quality of life (QOL).MethodsWe performed a retrospective chart review of 142 patients with ovarian cancer who had undergone systematic lymphadenectomy between 1995 and 2010. We assessed the distribution pattern of lymph node metastasis and the presence of CINDEIN metastasis according to the pT classification (pT1, pT2, and pT3).ResultsOf the 142 patients, 71, 21, and 50 were classified into pT1, pT2, and pT3, respectively. The lymph nodes most frequently involved were the para-aortic lymph nodes superior to the mesenteric artery (14%), followed by the obturator nodes (11%), the internal iliac nodes (9.4%), and the common iliac nodes (7.4%). Although the frequency of CINDEIN metastasis was 5.3% (6 of 114 cases with CINDEIN dissection), no metastasis to the CINDEINs was observed in pT1 patients.ConclusionsIt may be acceptable to omit CINDEIN dissection during surgery for pT1 ovarian cancer in view of postoperative QOL.

► The distribution pattern of positive lymph nodes was revealed through a chart review of 142 ovarian cancer patients.
► No CINDEIN metastasis was observed in pT1 patients, nor was any solitary CINDEIN metastasis observed in any patient.
► It may be rational to omit CINDEIN dissection, at least in pT1 ovarian cancer patients.