PMC4446482_01
Pelvic ultrasound. A large hypoechoic mass (asterisk) is seen in the prostatic loggia. The arrow indicates the urinary catheter.
CRIU2015-419180.001.jpg
PMC4446482_01_CRIU2015-419180.001.jpg
fig1
Pelvic ultrasound (US) showed an 8 x 7.5 x 8.5 cm lesion localized in the prostatic region and behind the bladder with heterogeneous mixed echogenicity (Figure 1).
CT of the pelvis, enhanced axial image. The asterisk is on the cystic component of the mass. The arrow shows the solid part of the lesion. B = bladder.
CRIU2015-419180.002.jpg
PMC4446482_01_CRIU2015-419180.002.jpg
fig2
MRI. Axial (a) and sagittal (b) T2-weighted images. Axial precontrast (c) and postcontrast (d) T1-weighted images. The asterisk is on the cystic component of the prostatic lesion; septa are evident. The arrow shows the solid component that improves after Gadolinium injection. Note the presence of a urinary catheter (arrowhead). B = bladder; R = rectum.
CRIU2015-419180.003.jpg
PMC4446482_01_CRIU2015-419180.003.jpg
fig3
The spindle cells are small, uniform, and closely packed and have a high nuclear-cytoplasmic ratio (a). Immunohistochemical staining showing scattered spindle cells positive for CK AE1/AE3 (b). Diffuse expression of BCL-2 (c) and CD99 (d) in spindle cells.
CRIU2015-419180.004.jpg
PMC4446482_01_CRIU2015-419180.004.jpg
fig4
The neoplastic cells were closely packed, growing in short interlacing and intersecting fascicles around a branching, "hemangiopericytoma-like vasculature" (Figure 4(a)). Immunohistochemical analysis showed pankeratin expression confined to scattered, individual spindle cells (Figure 4(b)), and diffuse expression of CD56, CD99 (Figure 4(c)), and BCL-2 (Figure 4(d)).
Photomicrograph of FISH results showing splitting of the fluorescent signal revealing SYT rearrangement.
CRIU2015-419180.005.jpg
PMC4446482_01_CRIU2015-419180.005.jpg
fig5
The fluorescence in situ hybridization (FISH) test for t(X;18)(p11q11) was positive showing splitting of the fluorescent signal consistent with a rearrangement involving SYT (Figure 5).
MRI. Postoperative images. Axial T2-weighted (a) and T1-weighted after contrast administration (b) images. Persistence of synovial sarcoma in the prostatic loggia.
CRIU2015-419180.006.jpg
PMC4446482_01_CRIU2015-419180.006.jpg
fig6
At 3 months of follow-up, after 6 cycles of chemotherapy, pelvic RMI showed persistence of the neoplasm, with cystic and solid component, confined in the prostatic loggia and with invasion of the right prostatic lobe (Figure 6).