Modelling Study with an Interactive Model Assessing the Cost-effectiveness of 68 Ga Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography and Nano Magnetic Resonance Imaging for the Detection of Pelvic Lymph Node Metastases in Patients with Primary Prostate Cancer

Eur Urol Focus. 2020 Sep 15;6(5):967-974. doi: 10.1016/j.euf.2019.02.013. Epub 2019 Feb 28.


Background: Outcomes of extended pelvic lymph node dissection (ePLND) show that only 16% of prostate cancer (PCa) patients harbour lymph node (LN) metastases. Ga-68 prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) and nano magnetic resonance imaging (nano-MRI) might be noninvasive alternatives for ePLND; however, it remains uncertain whether they are cost-effective.

Objective: To develop an interactive model to determine the cost-effectiveness of 68Ga PSMA PET/CT and nano-MRI as compared with ePLND for the detection of pelvic LN metastases in patients with intermediate- to high-risk PCa.

Design, setting, and participants: Decision tree with state transition model for men with intermediate- to high-risk PCa. Input data was derived from systematic literature searches.

Outcome measurements and statistical analysis: Quality-adjusted life years (QALYs) and healthcare costs were modelled over lifetime. Sensitivity analyses were used to assess uncertainty.

Results and limitations: Assuming 100% sensitivity of ePLND, no QALY loss after ePLND, and no treatment improvement due to imaging, the PSMA PET/CT and nano-MRI strategies seem to be less expensive per patient (€3047 and €2738, respectively) and result in loss of QALYs (0.07 and 0.03, respectively) compared with the ePLND strategy. PSMA PET/CT and nano-MRI are both cost saving and more effective when ePLND has a sensitivity of ≤60% and ≤84%, ePLND results in a QALY loss of 0.060 and 0.024 over lifetime, or the imaging techniques reduce recurrences by 26% and 8%, respectively.

Conclusions: PSMA PET/CT and nano-MRI seem to be cost-effective compared with ePLND since they save cost, but at the possible expense of a small QALY loss. Our interactive model provides insight into the influence of important model parameters on the cost effectiveness of 68Ga PSMA PET/CT and nano-MRI, and the opportunity for updating the cost effectiveness when new evidence becomes available.

Patient summary: We developed an interactive model that can be used in shared decision making regarding the use of extended pelvic lymph node dissection, 68Ga prostate-specific membrane antigen positron emission tomography/computed tomography, or nano magnetic resonance imaging for lymph node staging in individual patients with intermediate- to high-risk prostate cancer. Owing to remaining uncertainty, we cannot yet give advice about the use of these techniques.

Keywords: Cost-effectiveness analysis; Imaging; Lymph node metastases; Pelvic lymph node dissection; Prostate cancer.