Cost-effectiveness of minimally invasive surgery for women with ovarian masses

Abstract

<h3>Objectives:</h3> For women with suspicious ovarian cysts of varying risk of malignancy, treatment often involves minimally invasive surgery (MIS). While there are a number of benefits to MIS, there is an increased risk of ovarian capsule rupture during the procedure compared to laparotomy. Capsule rupture has the potential to seed the abdominal cavity with malignant cells. This upstaging is associated with a 10-15% decrease in progression free survival. As the utilization of MIS has increased, there has been a corresponding increase in capsule rupture. We developed a decision model to compare the risks, benefits and effectiveness of MIS versus laparotomy in women with ovarian masses. <h3>Methods:</h3> A decision model was created to simulate the clinical trajectory of a hypothetical cohort of 10,000 women aged 45 years with ovarian masses concerning for malignancy who were undergoing surgical management. The initial decision point in the model was performance of surgery via laparotomy or an MIS approach. The second node was whether the cyst ruptured intra-operatively. The base case analysis estimated outcomes if the risk of malignancy was 5%. Based on population data, the risk of rupture was 21% for those undergoing laparotomy versus 26% in those who underwent MIS. Model probabilities, costs and utility values were derived with assumptions drawn from published literature and administrative data sources. The effectiveness was calculated in terms of average quality adjusted life years (QALYs) gained. The primary outcome was incremental cost-effectiveness ratios (ICERs), expressed in 2018 US dollars/QALYs. One-way sensitivity analyses were performed to vary the assumptions across a range of plausible values. <h3>Results:</h3> MIS was the least costly strategy at $6,350, compared to a cost of $13,892 for laparotomy. In our hypothetical cohort, there were 64 cases of ovarian rupture in the MIS group and 53 in the open group (Table 1). There were 26 cancer related deaths in the MIS group and 25 in the laparotomy group. MIS was more effective than laparotomy (188,462 QALYs for MIS versus 187,631 QALYs for open) and MIS was cost-effective with an ICER of $-81,025/QALYs compared to laparotomy. In one-way sensitivity analyses, the probability of cancer and risk of rupture did not substantially impact the cost-effectiveness. <h3>Conclusions:</h3> MIS constitutes cost-effective management strategy for women with suspicious ovarian masses even though it is associated with both an increased risk of cyst rupture and death from ovarian cancer.