Histological examination
Sections from the left and right ocular tumors showed a picture of small
round cell tumor with high mitotic activity and tumor necrosis. The
tumor cells possessed neuroendocrine immunophenotype (NSE and
synaptophysin positivity). Diagnosis of Rb was established.
The sections from the left orbital and left tibia/femoral tumors
revealed chondroblastic and osteoblastic osteosarcoma, respectively,
with high grade, bizarre tumor cells proliferation and osteioid
production. The former sample also showed excess amount of malignant
cartilaginous component. The lung tumour showed classical osteoblastic
osteosarcoma indicating the metastatic nature from the lower leg. Key
histological features are shown in Figure 1 .