The addition of prostate radiation therapy to androgen deprivation therapy appears to be cost effective in patients with low-volume metastatic hormone-sensitive prostate cancer.
A combination of prostate radiation therapy (PRT) and androgen deprivation therapy (ADT) appeared to be a cost-effective option for patients with low-volume metastatic hormone-sensitive prostate cancer (mHSPC), according to a study published in JAMA Network Open.
The addition of PRT to ADT resulted in an increase of 0.16 quality-adjusted life-years (QALYs; 95% CI, 0.15-0.17) and a reduction in costs of $19,472 (95% CI, $16,333-$22,611) compared with ADT alone. Investigators reported similar results with a 6-week fraction regimen, noting a savings of $27,885 (95% CI, $23,272-$32,498) and a gain of 0.18 QALYs (95% CI, 0.17-0.19). After 37-months of follow-up, investigators reported a gain of 0.81 QALYs (95% CI, 0.73-0.89) and a savings of $30,229 (95% CI, $23,096-$37,362) with a lifetime of follow up.
“For patients with newly diagnosed low burden mHSPC, this economic evaluation supports PRT as a cost-effective treatment. The findings suggest that adjustments in the HR [hazard ratio] for progression in the [phase 2/3] STAMPEDE-H trial [NCT00268476] were associated with the cost-effectiveness of PRT. Our model was informed by high-quality data, and the addition of PRT to ADT was a dominant strategy compared with ADT alone across a wide range of assumptions,” the investigators wrote.
The analysis was based on findings from the STAMPEDE-H trial, which included 2061 patients. The economic evaluation was conducted with a microsimulation model in order to determine the cost effectiveness of both treatment regimens. A simulated cohort of 10,000 patients with low-volume disease was put together, and from January 2019 to July 2020, investigators pulled and analyzed data from patients. The median patient age was 68 years.
In the STAMPEDE-H trial, patients were randomized to receive standard of care ADT plus or minus PRT. PRT was administered at 55 Gy in 20 daily fractions at 2.75 Gy for 4 weeks or 36 Gy for 6 consecutive weekly fractions of 6 Gy. In patients with a low metastatic burden, the overall survival (OS) was improved in either regimen (HR, 0.68; 95% CI, 0.52-0.90; P = .007). Moreover, the 3-year OS rate was 81% in the PRT group compared with 73% in the comparator group.
Investigators found the univariable sensitivity analysis was sensitive to the HR for initial progression which was associated with PRT. Investigators noted an association between PRT and improved QALYs and a cost reduction for HRs less than 0.79. Overall, model parameters varied, but were not significantly changed because no thresholds were encountered.
An increased cost of $132,908 (95% CI, $111,482-$154,334) was observed in patients who received abiraterone and ADT, and abiraterone plus PRT had increased cost of $112,982 (95% CI, $94,768-$131,196) at the time of diagnosis. Moreover, net cost savings with PRT were similar ($21,996; 95% CI, $18,450-$25,541) and gains in QALYs were similar to base cases (0.18; 95% CI, 0.17-0.19), which could indicate a similar benefit associated with abiraterone between arms.
Lester-Coll NH, Ades S, Yu JB, Atherly A, Wallace HJ, Sprague BL. Cost-effectiveness of prostate radiation therapy for men with newly diagnosed low-burden metastatic prostate cancer. JAMA Netw Open. 2021;4(1):e2033787. doi:10.1001/jamanetworkopen.2020.33787