TRISST
Imaging Modality and Frequency in Surveillance of Stage I Seminoma Testicular Cancer: Results From a Randomized, Phase III, Noninferiority Trial (TRISST)
Phase 3N = 669NCT00589537
- Population
- Men who had undergone orchiectomy for stage I seminoma with no adjuvant therapy planned
- Design
- Phase III, noninferiority, 2 x 2 factorial trial in 35 UK centres, 2008 to 2014. Patients were randomly assigned to seven CTs (6, 12, 18, 24, 36, 48 and 60 months), seven MRIs (same schedule), three CTs (6, 18 and 36 months) or three MRIs. Primary outcome: 6-year incidence of Royal Marsden Hospital stage IIC or higher relapse (above 5 cm), aiming to exclude increases of 5.7% or more (from 5.7% to 11.4%) with MRI versus CT or with three versus seven scans; target N = 660, all patients contributing to both comparisons. Arms below are the pooled levels of the two factors, not the four cells.
- Primary endpoint
- Stage IIC or higher relapse incidence
- Arms
- Seven scans (CT and MRI pooled) (control, n = 336): Seven scans at 6, 12, 18, 24, 36, 48 and 60 months, CT or MRI
- Three scans (CT and MRI pooled) (experimental, n = 333): Three scans at 6, 18 and 36 months, CT or MRI
- CT (seven and three scans pooled) (control, n = 335): Surveillance imaging by CT
- MRI (seven and three scans pooled) (experimental, n = 334): Surveillance imaging by MRI
- People
- Joffe JK, TRISST Trial Management Group and Investigators
Δ Stage IIC or higher relapse incidence+2.5 pointsΔ Stage IIC or higher relapse incidence−2 points
Show the numbers
| Endpoint | Analysis | Three scans (CT and MRI pooled) / MRI (seven and three scans pooled) | Seven scans (CT and MRI pooled) / CT (seven and three scans pooled) | Effect |
|---|---|---|---|---|
| Stage IIC or higher relapse incidenceIntention-to-treat analysis (per-protocol analyses gave the same event counts)6-year incidence (Kaplan-Meier, weighted for minimisation factors) of Royal Marsden Hospital stage IIC or higher relapse, with the number of events in brackets in the source table. | primarymedian follow-up 72 monthsJoffe 2022 | 2.8% | 0.3% | Nine events with three scans (2.8%) versus one with seven scans (0.3%): absolute increase 2.5% (90% CI 1.0 to 4.1); statistically noninferior (margin 5.7%) but with a higher absolute event rate. Only 4 of the 9 events could potentially have been detected earlier with seven scans. Overall, 82 of 669 patients (12%) relapsed and stage IIC or higher relapse was rare (10 events). Five-year survival was 99% with no tumour-related deaths. The authors note that 8 of the 9 events occurred in the three-CT arm; the trial was not powered to assess interactions. |
| Stage IIC or higher relapse incidenceIntention-to-treat analysis (per-protocol analyses gave the same event counts)6-year incidence (Kaplan-Meier, weighted for minimisation factors) of Royal Marsden Hospital stage IIC or higher relapse, with the number of events in brackets in the source table. | primarymedian follow-up 72 monthsJoffe 2022 | 0.6% | 2.6% | Two events with MRI (0.6%) versus eight with CT (2.6%): 1.9% decrease (90% CI -3.5 to -0.3, labelled 90% in the full-text table); noninferiority of MRI versus CT was shown. |
| Endpoint | Analysis | Three scans (CT and MRI pooled) / MRI (seven and three scans pooled) | Seven scans (CT and MRI pooled) / CT (seven and three scans pooled) | Effect |
|---|---|---|---|---|
| Stage IIC or higher relapse incidenceIntention-to-treat analysis (per-protocol analyses gave the same event counts)6-year incidence (Kaplan-Meier, weighted for minimisation factors) of Royal Marsden Hospital stage IIC or higher relapse, with the number of events in brackets in the source table. | primarymedian follow-up 72 monthsJoffe 2022 | 2.8% | 0.3% | Nine events with three scans (2.8%) versus one with seven scans (0.3%): absolute increase 2.5% (90% CI 1.0 to 4.1); statistically noninferior (margin 5.7%) but with a higher absolute event rate. Only 4 of the 9 events could potentially have been detected earlier with seven scans. Overall, 82 of 669 patients (12%) relapsed and stage IIC or higher relapse was rare (10 events). Five-year survival was 99% with no tumour-related deaths. The authors note that 8 of the 9 events occurred in the three-CT arm; the trial was not powered to assess interactions. |
| Stage IIC or higher relapse incidenceIntention-to-treat analysis (per-protocol analyses gave the same event counts)6-year incidence (Kaplan-Meier, weighted for minimisation factors) of Royal Marsden Hospital stage IIC or higher relapse, with the number of events in brackets in the source table. | primarymedian follow-up 72 monthsJoffe 2022 | 0.6% | 2.6% | Two events with MRI (0.6%) versus eight with CT (2.6%): 1.9% decrease (90% CI -3.5 to -0.3, labelled 90% in the full-text table); noninferiority of MRI versus CT was shown. |