Comparison of gadobenate dimeglumine (Gd-BOPTA) with gadopentetate dimeglumine (Gd-DTPA) for enhanced MR imaging of brain and spine tumours in children

Background: Gadobenate dimeglumine (Gd-BOPTA) demonstrates superior enhancement of brain tumours in adult patients than Gd-DTPA. Objective: To determine whether Gd-BOPTA has advantages over Gd-DTPA for enhanced MR imaging of paediatric brain and spine tumours. Materials and methods: Sixty-three subjects, aged 6 months to 16 years, who were enrolled in a prospective, fully blinded, randomized parallel-group phase III clinical trial, received 0.1 mmol/kg doses of either Gd-BOPTA (n = 29) or Gd-DTPA (n = 34). The MR images were acquired before and within 10 min of contrast agent injection. The primary objective was to compare the difference from pre-dose to post-dose lesion visualization between Gd-BOPTA and GdDTPA. Lesion visualization was determined as the sum of individual scores for three criteria of lesion morphological characteristics ( lesion border delineation, internal morphology, and contrast enhancement), each assessed qualitatively using 4-point scales. Quantitative evaluation compared changes in lesion-to-background (LBR) and contrast-to-noise (CNR) ratios and per cent enhancement. Monitoring for adverse events and evaluation of vital signs and laboratory values was performed. Results: Pre-dose to post-dose changes in lesion visualization were significantly better for Gd-BOPTA for both lesion level (2.68 +/- 2.17 vs. 1.05 +/- 1.90, P = 0.0106) and patient level (2.55 +/- 2.18 vs. 1.14 +/- 1.68, P= 0.0079) comparisons. The mean pre-dose to post-dose change in CNR was greater for Gd-BOPTA (9.13 +/- 15.36) than Gd-DTPA ( 2.18 +/- 9.90), but the difference was only marginally significant ( P= 0.0779; 95% CI: -0.553, 14.454) because of wide variations of signal intensity between lesions. Similar findings were obtained for LBR and per cent enhancement. No differences between the agents were noted in terms of safety parameters. Conclusions: At an equivalent dose Gd-BOPTA is significantly better than Gd-DTPA for visualization of enhancing CNS tumours in paediatric patients.