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. 2022 Jul;32(4):e13057.
doi: 10.1111/bpa.13057. Epub 2022 Feb 27.

Brachial plexus lipomatosis with perineurial pseudoonion bulb formation: Result of a mosaic PIK3CA mutation in the para-axial mesoderm state

Blake A Ebner  1 , Kathryn L Eschbacher  1 , Megan M Jack  2 , Milosevic Dragana  1 , Robert J Spinner  2 , Caterina Giannini  1
Affiliations

Brachial plexus lipomatosis with perineurial pseudoonion bulb formation: Result of a mosaic PIK3CA mutation in the para-axial mesoderm state

Blake A Ebner et al. Brain Pathol. 2022 Jul.
No abstract available

Keywords: PIK3CA-related overgrowth spectrum; brachial plexus; lipomatosis of nerve; perineurial cell pseudo-onion bulb; segmental overgrowth.

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Conflict of interest statement

All authors have no conflict of interest to report.

Figures

FIGURE 1
FIGURE 1
(A) Gross image of spinal cord and left brachial plexus demonstrating diffuse enlargement. Red dots indicate the site tested for PIK3CA mutation by digital droplet PCR (ddPCR). Table 1 lists PIK3CA H1047R allele relative frequency per brachial plexus segment (%). Intradural and dural sleeve components were separated at the roots (C5, C6, C7 and T1). Epineurium and endoneurium compartments were isolated from inferior trunk and cords. (B) Representative H&E images of the medial cord demonstrating extensive adipose infiltration of the epineurium separating nerve fascicles. (C) High magnification of square inset with PPOB formation
See this image and copyright information in PMC

References

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