PMC6704251_01
Magnetic resonance imaging. (A) T1 weighted sagittal image of a heterogeneously iso- to hyperintense intramuscular ovoid lesion, with flow voids noted peripherally (white arrow) suggestive of either a possible fast flow vascular malformation or vessels supplying a vascular lesion. (B) Axial short tau inversion recovery image, showing a heterogeneously hyperintense lesion; again, flow voids suggestive of vessels are seen adjacent to it (white arrow). No significant perilesional oedema is present to suggest surrounding muscular infiltration. (C) Post-gadolinium T1 weighted fat saturated sagittal image demonstrating intense lesional enhancement, similar to the gadolinium enhanced vessel (white arrow). This suggests either a hypervascular lesion or a fast flow vascular malformation (note the adjacent flow voids, as in A and B).
gr1.jpg
PMC6704251_01_gr1.jpg
fig1
Subsequent magnetic resonance imaging showed a well defined fusiform lesion with heterogenous signal intensity within the left brachioradialis muscle (Fig. 1).
Intra-operative specimen of the ovoid, arteriovenous malformation mimicking a vascular tumour, excised from the left brachioradialis muscle. The main feeding vessel was seen to arise from the recurrent radial artery (intra-operatively).
gr2.jpg
PMC6704251_01_gr2.jpg
fig2
Intra-operatively there was a benign looking lesion, with a smooth surface, encapsulated by a thick fibrous wall (Fig. 2).
Histopathology images. (A) Malignant clear cells in acinar pattern interspersed with numerous thin walled vessels. (B, C) Immunohistochemistry staining showed malignant cells with positivity for CD10 and vimentin. (D) CD34 highlights the blood vessels.
gr3.jpg
PMC6704251_01_gr3.jpg
fig3
Surprisingly, histopathological examination of the specimen was consistent with metastatic RCC (Fig. 3).