Figure legends:
Figure 1 . Tumor imaging findings
(a–d) A tumor measuring approximately 1.5 cm can be visualized in the left cerebellopontine angle (red arrow).
(a) Contrast enhancement effect was observed only in the anterior area on gadolinium-enhanced, T1-weighted images. (b) Diffusion-weighted images showed diffusion limitation. (c–f) The tumor appeared to be continuous with the left border of the pons. (d) The right trigeminal nerve (green arrowhead) is compressed by the tumor.
(g and h) The tumor morphologically consists mainly of large nodular structures with well-defined borders, and low-to-moderate cell densities within the nodules. Between the nodules, cells with a high N/C ratio and round nuclei with densely packed hyperchromatic chromatin are observed. (i) Silver staining reveals reticular fibers in the dark background surrounding the bright nodules. (j) The MIB-1 index is low at the nodules, but high at 68% around the nodules.
Figure 2. DNA sequencing
(a) DNA sequencing of normal tissue confirms the germline pathogenic variant of PTEN . (b) Copy number analysis of the tumor reveals copy number neutral loss of heterozygosity of chromosome 10q, wherePTEN is located.