Comparing survival of older ovarian cancer patients treated with neoadjuvant chemotherapy versus primary cytoreductive surgery: Reducing bias through machine learning.

OBJECTIVE: To develop and evaluate a multidimensional comorbidity index (MCI) that identifies ovarian cancer patients at risk of early mortality more accurately than the Charlson Comorbidity Index (CCI) for use in health services research. METHODS: We utilized SEER-Medicare data to identify patients with stage IIIC and IV ovarian cancer, diagnosed in 2010-2015. We employed partial least squares regression, a supervised machine learning algorithm, to develop the MCI by extracting latent factors that optimally captured the variation in health insurance claims made in the year preceding cancer diagnosis, and 1-year mortality. We assessed the discrimination and calibration of the MCI for 1-year mortality and compared its performance to the commonly-used CCI. Finally, we evaluated the MCI's ability to reduce confounding in the association of neoadjuvant chemotherapy (NACT) and all-cause mortality. RESULTS: We included 4723 patients in the development cohort and 933 in the validation cohort. The MCI demonstrated good discrimination for 1-year mortality (c-index: 0.75, 95% CI: 0.72-0.79), while the CCI had poor discrimination (c-index: 0.59, 95% CI: 0.56-0.63). Calibration plots showed better agreement between predicted and observed 1-year mortality risk for the MCI compared with CCI. When comparing all-cause mortality between NACT with primary cytoreductive surgery, NACT was associated with a higher hazard of death (HR: 1.13, 95% CI: 1.04-1.23) after controlling for tumor characteristics, demographic factors, and the CCI. However, when controlling for the MCI instead of the CCI, there was no longer a significant difference (HR: 1.05, 95% CI: 0.96-1.14). CONCLUSIONS: The MCI outperformed the conventional CCI in predicting 1-year mortality, and reducing confounding due to differences in baseline health status in comparative effectiveness analysis of NACT versus primary surgery.

Cost-effectiveness of lenvatinib plus pembrolizumab versus chemotherapy for recurrent mismatch repair-proficient endometrial cancer after platinum-based therapy.

OBJECTIVE: The recent Study 309-KEYNOTE-775 showed improved survival for lenvatinib plus pembrolizumab compared to chemotherapy in patients with recurrent endometrial cancer. We created a decision model to compare the cost-effectiveness of lenvatinib plus pembrolizumab in patients with recurrent mismatch repair-proficient (pMMR) endometrial cancer who had progressed after first-line chemotherapy. METHODS: A Markov model was created to simulate the clinical trajectory of 10,000 patients with recurrent pMMR endometrial cancer. The initial decision point in the model was treatment with ether lenvatinib plus pembrolizumab or chemotherapy (doxorubicin or dose-dense paclitaxel). Model probabilities, utility values and costs were derived with assumptions drawn from published literature. A cycle length of 3 months and a time horizon of 2 years was used. 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 2020 US dollars/QALYs. One-way, two-way and probabilistic sensitivity analyses were performed. RESULTS: Chemotherapy was the least costly strategy at $66,693 followed by lenvatinib plus pembrolizumab ($193,590). Lenvatinib plus pembrolizumab resulted in more patients being alive at 2 years (lenvatinib plus pembrolizumab: 367, chemotherapy: 109). Chemotherapy was cost-effective compared with lenvatinib plus pembrolizumab (ICER: $164,493/QALYs). Lenvatinib plus pembrolizumab became cost-effective when its cost was reduced by $1553 per month (7.8% reduction). CONCLUSION: For patients with recurrent pMMR endometrial cancer Lenvatinib plus pembrolizumab is associated with greater survival but is more costly than chemotherapy. The cost of lenvatinib and pembrolizumab would have to be reduced by approximately 7% to be considered cost-effective.

Cost-effectiveness of BRCA1 testing at time of obstetrical prenatal carrier screening for cancer prevention.

BACKGROUND: Improved technologies paired with an increase in access to genetic testing have led to the availability of expanded carrier screening evaluating hundreds of disorders. Currently, most autosomal dominant mutations, such as BRCA1, are not included in expanded carrier assays. Screening pregnant or preconception reproductive-aged women for BRCA1 may present a unique opportunity to perform population-based screening for patients at a time when precancer screening, chemoprevention, and/or risk-reducing surgery may be beneficial. OBJECTIVE: This study aimed to inform clinical decision-making as to whether the universal incorporation of BRCA1 testing at the time of obstetrical prenatal carrier screening is cost-effective. STUDY DESIGN: A decision analysis and Markov model was created. The initial decision point in the model was BRCA1 testing at the time of expanded carrier screening. Model probabilities, cost, and utility values were derived from published literature. For BRCA1-positive patients, the model simulated breast cancer screening and risk-reducing surgical interventions. A cycle length of 1 year and a time horizon of 47 years were used to simulate the lifespan of patients. The setting was obstetrical clinics in the United States, and the participants were a theoretical cohort of 1,429,074 pregnant patients who annually underwent expanded carrier screening. RESULTS: Among our cohort, BRCA1 testing resulted in the identification of an additional 3716 BRCA1-positive patients, the prevention of 1394 breast and ovarian cancer cases, and 1084 fewer deaths. BRCA1 testing was a cost-effective strategy compared with no BRCA1 testing with an incremental cost-effectiveness ratio of $86,001 per quality-adjusted life years. In a 1-way sensitivity analysis, we varied the prevalence of BRCA1 in the population from 0.00% to 20.00% and found that BRCA1 testing continued to be the cost-effective strategy until the prevalence rate was reduced to 0.16%. Multiple additional sensitivity analyses did not substantially affect the cost-effectiveness. CONCLUSION: The addition of BRCA1 testing to obstetrical prenatal carrier screening is a cost-effective management strategy to identify at-risk women at a time when cancer screening and preventive strategies can be effective. Despite the burden of additional genetic counseling, prenatal care represents a unique opportunity to implement population-based genetic testing.