Men with early-stage testicular cancer could avoid potentially harmful scans
18 Mar 2022
Men who have had treatment for early-stage testicular cancer could benefit from fewer monitoring scans, freeing them from some of the harmful radiation that comes from computerized tomography (CT) imaging, according to results from the TRISST clinical trial published yesterday in the Journal of Clinical Oncology.
The TRISST study also found that using magnetic resonance imaging (MRI) instead of CT scans was just as good at picking up signs of cancer relapse, when the cancer comes back after treatment.
Using fewer CT scans, or swapping these for MRI, would mean less exposure to potentially harmful radiation, which is particularly important when monitoring young men who are unlikely to die from testicular cancer.
Currently, men with stage one testicular cancer, which accounts for 40-50% of cases, have surgery to remove the affected testicle, and are monitored to see if the cancer has come back by having regular CT scans for 5 years. While essential, having a CT scan exposes men to some radiation, which may slightly increase their risk of developing other cancers.
Because of this, doctors want to find out if men can have CT scans less often, or have MRI scans instead, which don’t use radiation, without seeing an unacceptable increase in cases where the cancer is only detected in its advanced stage.
In the largest study of its kind, the TRISST trial recruited 669 men with stage one testicular cancer who had surgery to remove the affected testicle. Men were monitored either using the standard 7 CT scans, 3 CT scans, or the same two regimes using MRI scans.
Results showed that the proportion of men whose cancer returned was 12% (82 men), but only a small proportion of 1.5% (10 men) had advanced stage disease at detection. Most relapses happened within 3 years, suggesting that scanning beyond 3 years may be unnecessary.
The proportion of men with relapses detected at advanced stage was 2.8% (9 men) in the 3-scan group compared to 0.3% (1 man) in the 7-scan group. While this shows that some of the more advanced-stage relapses could have been detected earlier with 7 scans rather than 3, all men who relapsed were treated successfully. This indicates that the risks of the additional scans didn’t outweigh the benefits of fewer scans.
When comparing the two types of scans, relapses were more likely to be detected at an advanced stage with CT (2.6%), compared with MRI (0.6%), but the difference was small, and all men were treated successfully regardless of which scans they had.
In conclusion, TRISST showed that testicular cancer relapses can still be detected at an early-stage, and successfully treated, with fewer scans and using MRI rather than CT.
Further work is ongoing to assess the cost-effectiveness of MRI scans, to see if 3 MRI scans could be recommended as the standard surveillance plan in the future.