Hysterectomy with sentinel lymph node dissection in the setting of preoperative endometrial intraepithelial neoplasia and an endometrial stripe ≥20 mm: a cost-effectiveness analysis

Objectives Routine lymph node assessment in patients with endometrial intraepithelial neoplasia is institution and surgeon-dependent without clear guidelines. We sought to determine if routine sentinel lymph node (SLN) dissection at the time of laparoscopic hysterectomy for patients with a preoperative diagnosis of endometrial intraepithelial neoplasia and a preoperative ultrasound with endometrial stripe >= 20 mm is cost-effective. Methods A decision model was created to perform two cost-effectiveness analyses: (1) hysterectomy with frozen section versus hysterectomy with SLN dissection in patients with a preoperative diagnosis of endometrial intraepithelial neoplasia and an endometrial stripe of 20 mm or greater, and (2) the same options in all patients with a preoperative diagnosis of endometrial intraepithelial neoplasia. Costs obtained from Centers for Medicare and Medicaid Services and event probabilities and quality of life utility values were obtained through literature review. Results In the case of preoperative endometrial stripe >= 20 mm, hysterectomy with SLN dissection cost $2469 more than hysterectomy with frozen section and gained 0.010 quality adjusted life years, or $44,997/quality-adjusted life years gained. In one-way sensitivity analyses, SLN dissection remained the favored strategy at a willingness to pay threshold of $100,000/quality-adjusted life years unless chronic lower extremity lymphedema after full lymphadenectomy had a likelihood <13.1% (base case value 18.1%); otherwise, SLN dissection was favored with individual variation of all other parameters over plausible ranges. When considering all patients with endometrial intraepithelial neoplasia, hysterectomy with frozen section was favored, with results most sensitive to variation of lymphedema risk after full lymphadenectomy. Conclusion Hysterectomy with SLN dissection in patients with a preoperative endometrial stripe >= 20mm on ultrasound is cost-effective when compared with hysterectomy with frozen section.