Aggressive angiomyxoma with diffusion-weighted magnetic resonance imaging and dynamic contrast enhancement: a case report and review of the literature

Abstract

Introduction: Aggressive angiomyxoma (AA) is a rare benign soft tissue tumour usually affecting the pelvis and perineum of young women. Magnetic resonance imaging (MRI) is crucial in the management of AA patients for its diagnostic contribution and for the preoperative assessment of the actual tumour extension. Given the current development of less aggressive therapeutics associated with a higher risk of recurrence, close follow-up with MRI is fundamental after treatment. In this context, diffusion-weighted (DW) imaging has already shown high efficacy in the detection of early small relapses in prostate or rectal cancer.

Case report: We report here a case of pelvic AA in a 51-year-old woman examined with dynamic contrast enhancement and DW-MRI, including apparent diffusion coefficient mapping and calculation.

Conclusion: To our knowledge, this is the first description of DW-MRI in AA reported in the literature. Here, knowledge about imaging features of AA will be reviewed and expanded.

Keywords: Aggressive angiomyxoma; Diffusion-weighted imaging; Dynamic contast enhancement; Magnetic resonance imaging.

Fig. 1

Sagittal (a), coronal (b), and axial (c) T2-weighted MR images in a 51-year-old woman with AA show a bulky perineal and intrapelvic tumour displacing rather than infiltrating the vagina, anal canal, and rectal structures (black arrows). The mass presents typical high signal intensity with layered strands of lower signal intensity and swirled architecture (stars). Finger-like projections into the underlying adipose tissue can be seen (white arrows). d Sagittal T1-weighted MR image shows a homogeneous tumour, isointense relative to muscle, with a fat linear structure of high signal intensity inside (arrowheads).

Fig. 2

Sagittal T1-weighted MR imaging after intravenous contrast injection with 0.1 mmol/kg gadoteric acid (Gd-DOTA, Dotarem, Guerbet, Roissy, France) at 2.5 ml/s in a 51-year-old woman with AA. a The mass presents a heterogeneous enhancement with layered architecture (black lines). b, c The tumour's DCE analysis shows a progressive curve without plateau or washout. DCE mapping shows the same layered pattern. Regions of interest located in the layers demonstrate the same profile curves of progressive enhancement with variable intensity.

Fig. 3

Axial T2-weighted MR image (a, d) and axial DWI (b, c, e) in a 51-year-old woman with AA. DWI sequences show heterogeneous high signal intensity on b0 (b) and b1000 (c, e) sequences. Typical architecture is only observed on b0 sequences. f ADC mapping shows a high value in the tumour, and ADC calculations are estimated at 2 × 10⁻³ (±0.15) mm²/sec.