Final results of S1823/GCC.1: A prospective observational cohort study to assess miR371a-3p (miR371) for outcome prediction in patients (pts) with newly diagnosed germ cell tumors (GCT)

S1823/GCC.1

Patient / Population Intervention / Exposition Vergleich Endpunkt

In patients with early-stage germ cell tumours on active surveillance, plasma miR371 detected relapse with a sensitivity of 0.54 at relapse and a specificity of 0.90.

N

963Patienten

Design

International prospective observational cohort study of 963 patients with newly diagnosed germ cell tumours, with plasma miR371 measured by RT-PCR at baseline and every 6-12 months according to relapse risk during active surveillance for early-stage disease, for up to 3 years or until relapse (NCT04435756).

Endpunkt

Operating characteristics of plasma miR371 (sensitivity, specificity, negative and positive predictive value and AUC) for relapse during active surveillance in early-stage germ cell tumours, followed for up to 3 years or until relapse.

Ergebnis631 patients on active surveillance contributed to the primary endpoint. Median follow-up was 35.9 months with 104 relapses, 90 of which were confirmed as unequivocal. Specificity of miR371 was 0.90 (95% CI 0.87-0.92). Sensitivity was 0.20 (95% CI 0.10-0.29) at baseline and 0.54 (0.43-0.65) at relapse. Reported NPV values were 0.90 (0.86-0.92) and 0.92 (0.90-0.95), PPV values 0.21 (0.11-0.31) and 0.46 (0.35-0.56), and AUC values 0.55 (0.50-0.61) and 0.74 (0.67-0.80). miR371 was positive in 21% of relapsing patients at baseline and 54% at relapse. False positives were 10.3% at baseline and 4.4% at 12 months. Patients with positive baseline miR371 were twice as likely to relapse as those with negative baseline miR371 (HR 2.04, P = 0.02). Relative miR371 expression rose over time in relapsed patients compared with non-relapsed patients.

Nappi L, Colby S, Hamilton R, et al. Presented at ESMO Congress 2026, abstract LBA58, 26 October. Not yet published.

Diskussion & Kritik

This large prospective cohort gives serial plasma miR371 data during active surveillance with nearly 3 years of median follow-up, and specificity and negative predictive value are high. Sensitivity is modest, though: 0.20 at baseline and 0.54 at relapse, with a baseline AUC of 0.55. That fits poorly with the conclusion of 'high accuracy'. The abstract gives no figures for conventional markers or imaging, so the claim that miR371 outperformed current tools cannot be checked here. Only 631 of 963 enrolled patients contributed to the primary endpoint, only 90 of 104 relapses were confirmed as unequivocal, the table does not clearly match every value to a time point, and the authors state that how best to integrate the test into routine practice remains unknown.