Cost-effectiveness of 2-[18F]FDG-PET/CT versus CE-CT for response monitoring in patients with metastatic breast cancer: a register-based comparative study

We evaluated the cost-effectiveness of 2-[18F]FDG-PET/CT compared to CE-CT for response monitoring in metastatic breast cancer (MBC) patients. The study included 300 biopsy-verified MBC patients treated at Odense University Hospital (Denmark). CE-CT was used in 144 patients, 83 patients underwent 2-[18F]FDG-PET/CT, and 73 patients received a combination of both. Hospital resource-based costs (2007-2019) were adjusted to the 2019 level. The incremental cost-effectiveness ratio (ICER) was calculated by comparing average costs per patient and gained survival with CE-CT. During a median follow-up of 33.0 months, patients in the 2-[18F]FDG-PET/CT group had more short admissions (median 6 vs. 2) and fewer overnight admissions (5 vs. 12) compared to the CE-CT group. The mean total cost per patient was €91,547 for CE-CT, €83,965 for 2-[18F]FDG-PET/CT, and €165,784 for the combined group. The ICER for 2-[18F]FDG-PET/CT compared to CE-CT was €-527/month, indicating gaining an extra month of survival at a lower cost (€527). 2-[18F]FDG-PET/CT was more cost-effective in patients with favorable prognostic factors (oligometastatic or estrogen receptor-positive disease), while CE-CT was more cost-effective in poor prognosis patients (liver/lung metastases or performance status ≥ 2 at baseline). In conclusion, our study suggests that 2-[18F]FDG-PET/CT is a cost-effective modality for response monitoring in metastatic breast cancer.

Response monitoring in metastatic breast cancer: a comparison of survival times between FDG-PET/CT and CE-CT

BACKGROUND

We compared overall survival for metastatic breast cancer (MBC) patients monitored with CE-CT, FDG-PET/CT or a combination of them in an observational setting.

METHODS

Patients with biopsy-verified (recurrent or de novo) MBC (n = 300) who were treated at Odense university hospital (Denmark) and response monitored with FDG-PET/CT (n = 83), CE-CT (n = 144), or a combination of these (n = 73) were followed until 2019. Survival was compared between the scan groups, and were adjusted for clinico-histopathological variables representing potential confounders in a Cox proportional-hazard regression model.

RESULTS

The study groups were mostly comparable regarding baseline characteristics, but liver metastases were reported more frequently in CE-CT group (38.9%) than in FDG-PET/CT group (19.3%) and combined group (24.7%). Median survival was 30.0 months for CE-CT group, 44.3 months for FDG-PET/CT group and 54.0 months for Combined group. Five-year survival rates were significantly higher for FDG-PET/CT group (41.9%) and combined group (43.3%), than for CE-CT group (15.8%). Using the CE-CT group as reference, the hazard ratio was 0.44 (95% CI: 0.29-0.68, P = 0.001) for the FDG-PET/CT group after adjusting for baseline characteristics. FDG-PET/CT detected the first progression 4.7 months earlier than CE-CT, leading to earlier treatment change.

CONCLUSIONS

In this single-center, observational study, patients with metastatic breast cancer who were response monitored with FDG-PET/CT alone or in combination with CE-CT had longer overall survival than patients monitored with CE-CT alone. Confirmation of these findings by further, preferably randomised clinical trials is warranted.