Pseudovascular Invasion: Minimally Invasive Surgery for Endometrial Cancer

To determine if the use of an intrauterine manipulator is associated with an increased incidence of pseudovascular invasion on pathologic evaluation of hysterectomy specimens for endometrial cancer and to assess the possible implications of pseudovascular space invasion in the treatment of endometrial cancer.

We performed a retrospective cohort study of patients with early stage (I/II) endometrial cancer who underwent minimally invasive surgical staging. The following data were abstracted: race, body mass index, grade, age, stage, histology, presence or absence of lymphovascular space invasion (LVSI), peritoneal cytology, and adjuvant treatment. Slides were blindly reviewed by a gynecologic pathologist.

Of the104 patients meeting eligibility criteria, 74 cases were reviewed in detail (the study was terminated early based on the results of an interim analysis). Patients in the no-manipulator group were older (P = .02) and had a higher stage 1B/II (P = .01) than patients in the manipulator group. No difference was found in the incidence of pseudovascular invasion between the manipulator and the no-manipulator groups (P = .86). Subgroup analysis showed no association of pseudovascular invasion with tumor grade (P = .79). Five patients were identified to have pseudovascular invasion misdiagnosed as true LVSI-4 had endometrioid and 1 had serous histology. Of these, 3 were in the manipulator group. Two received adjuvant radiotherapy which they not have gotten, absent reported lymphovascular invasion.

The use of a uterine manipulator does not appear to increase the rate of pseudovascular invasion in our limited data set. Misdiagnosis of pseudovascular invasion as LVSI can result in risk migration of patients with potential for harm from unwarranted adjuvant therapy.