Comparative cost-effectiveness of alternative imaging and surveillance schedules for testicular seminoma

The risk of radiation exposure from standard computed tomography (CT) surveillance is a major concern in the management of stage I seminoma testis patients. TRISST data are used to evaluate the economic consequences and health outcomes of different surveillance schedules in seminoma patients in the UK. Overall, only small differences exist in total costs and total quality-adjusted life years between different strategies.

The radiation exposure of CT scans is an important consideration in the management of stage I seminoma testicular cancer patients. These patients, with a survival rate of almost 100%, are routinely followed for a long period of time using CT scans. The randomised TRISST trial has already shown that the tumour can also be effectively monitored with a schedule with a lower scanning frequency or in which MRIs are used instead of CT. However, thus far it remained unclear what the impact of these different surveillance schedules would be on cost-effectiveness and quality of life.

Study design

In the study, 669 men with a seminoma testicular tumour were randomised to four different surveillance groups, each of whom underwent one of the following monitoring schedules:

• 7 abdominal CT scans over a period of 5 years (N= 169)
• 3 abdominal CT scans over a period of 3 years (N= 166)
• 7 abdominal MRI scans over a period of 5 years (N= 167)
• 3 abdominal MRI scans over a period of 3 years (N= 167)

At the start of the study and over a six-year period, health outcomes (EQ-5D 3L), the number of hospitalisations and any treatment for relapses were tracked. In addition, it was determined how much costs were incurred for the monitoring. Furthermore, the quality-adjusted life years (QALYs) were also determined for each scheme in order to determine the relationship between the costs and the savings in burden of disease.

Results

Mean age of the patients was 39 years and most (87%) had T1 tumours. In those patients remaining in surveillance, compliance was good with 94% of scans attended, of which 79% were on time (+/- 4 weeks). Recurrence was seen in 12% of men (N= 82), so most health care consumption occurred in the disease-free period. Patients who underwent 7 MRI scans showed a slightly increased health benefit (5.20 QALYs) but at a higher cost (£5,761) compared to the other schemes. At a cutoff of £20,000/QALY, the probability of 7 MRIs being cost effective was 64%. In addition, 3 MRIs, 7 CT scans and 3 CT scans showed a similar health benefit (5.10-5.12 QALYs), with higher costs using 3 CT scans (£5,606) and comparable costs between 3 MRIs and 7 CT scans (£5,075 and £5,049 respectively). These increased costs for 3 CT scans were mainly due to the more frequent occurrence of (advanced) recurrences and the subsequent treatments. The probability that 7 CT scans were cost effective at the £20,000/QALY cutoff was 36%.

Conclusion

Most health resource consumption happened during the disease-free period due to investigations (including blood tests, chest X-ray, equivocal scans, clinical assessment). There were only small differences in total costs and total QALYs across all strategies. The higher cost of 3 CT is driven by a larger number of relapses and more advanced relapses. If one whishes to avoid the radiation exposure of 7 CT, 3 MRI has a similar cost and HRQoL to 7 CT and is therefore a logical choice without significant increase in cost. 7 MRI provides most HRQoL benefits (although small) but comes at a higher cost.  However, 7 MRI is still likely to be more cost-effective than 7 CT.

Reference

Huo D, et al. Comparative cost-effectiveness of alternative imaging and surveillance schedules for testicular seminoma in the TRISST trial. Presented at ASCO GU 2023; Abstract 408.