Dentate nucleus signal changes after multiple GBCAs MRI in breast cancer patients: A generalized additive model retrospective study.

BACKGROUND

While research has explored gadolinium retention differences between linear and macrocyclic GBCAs, comparative studies of structurally distinct linear subtypes (ionic vs. nonionic) in high-dose, large cohorts remain limited.

PURPOSE: To investigate factors influencing dentate nucleus (DN) signal increase on non-contrast T1WI after multiple GBCA administrations in breast cancer patients, focusing on contrast type (nonionic gadodiamide vs. ionic gadopentetate), interdose intervals, and adjuvant therapies.

STUDY TYPE: Cohort study.

POPULATION: 197 female breast cancer patients (excluded from 332) with ≥3 GBCA-enhanced scans and ≥ 2 non-enhanced cranial MRIs (2016-2023), mean age 51.5 years (26-78).

FIELD STRENGTH/SEQUENCE: 1.5 T and 3.0 T, turbo spin-echo inversion recovery sequence ASSESSMENT: Blinded DN/pons signal ratio measurements; relative change (Rchange) reflected gadolinium retention. Associations between Rchange and covariates (contrast type, intervals, therapies, etc.) were analyzed.

STATISTICAL TESTS: Generalized additive models (GAMs) and intraclass correlation coefficients (ICC).

RESULTS

107 patients received gadodiamide (mean 7.17 administrations), 60 gadopentetate (mean 7.15), 30 Mixed GBCA (mean 6.80). Excellent interobserver agreement (ICC: 0.860-0.862). GAM showed higher Rchange in gadodiamide vs. gadopentetate (0.080 ± 0.041 vs 0.056 ± 0.034; 1.43-fold, P < 0.001). Rchange inversely correlated with interdose intervals (P < 0.001) and hormonal therapy (P = 0.021), with no associations with chemotherapy, targeted therapy, calcium supplementation, or age (all P > 0.05).

DATA

CONCLUSION

Nonionic linear gadodiamide has higher intracranial gadolinium retention propensity than ionic linear gadopentetate. Interdose intervals and hormonal therapy are significant modulators.