Measuring the Cost-Effectiveness of Hormonal Therapy in Ovarian Cancer Patients

Letrozole, a maintenance hormone therapy could be a cost-effective strategy for patients being treated for low-grade, serious ovarian cancer (LGSC), explained researchers at the Society of Gynecologic Oncology’s 2020 Annual meeting.

Researchers from the University of Toronto simulated a decision analysis using a Markov model over a lifetime horizon, using the base case of a 47-year-old female with stage III, estrogen-receptor positive LGSC after primary treatment with cytoreductive surgery and adjuvant chemotherapy.

Maintenance letrozole until progression and routine observation were the two treatment strategies examined. 

The researchers used probability and utility data from existing literature and estimated direct medical costs using public sources adjusted for 2018 CAD, in order to estimate overall lifetime cost, quality-adjusted life-years (QALY), absolute life years (LY), median overall survival (OS), and number of reoccurrences within each treatment strategy.

“Maintenance letrozole was the preferred strategy with an associated lifetime cost of $69,985 CAD and an observed improvement of 0.91 QALY and 1.55 LYs,” found the researchers.

Futher, with an additional lifetime cost of $10,016 CAD, the incremental cost-effectiveness ratio for letrozole maintenance therapy was found to be $11,037 CAD per QALY.

OS for patients treated with maintenance letrozole and routine observation groups was 150 months and 126 months, respectively. Maintenance letrozole also resulted in fewer first reoccurrences at 5-year (34%) and 10-year (17%) follow-ups. 

A sensitivity analysis proved the model to be robust over a broad range of values and was sensitive to the probability of reoccurrence with observation and with maintenance letrozole, the researchers explained. 

“When the probability of recurrence with observation alone was set at 27% per year, which was derived from previous literature, letrozole maintenance was cost-effective if the probability of recurrence with therapy was set at less than 24% per year,” noted the researchers. 

Because of these results, the researchers concluded that “maintenance letrozole is a cost-effective strategy in patients with treated LGSC resulting in a clinically relevant improvement in QALY, LY, and decreased number of recurrences.”—Edan Stanley