Fig. 2

LFS MB and sarcoma progressing after radiotherapy for atypical prolactinoma. A MRI showing a macroadenoma compressing the optic chiasm and the floor of the 3rd ventricle. B H&E of the macroadenoma shows patchy lymphocytic inflammatory infiltrates (blue arrow), mitotic figures (green arrowhead) and glandular structures (red arrow). C, D IHC with indicated antibodies distinguishes the neoplastic cells from non-neoplastic inflammatory infiltrates (blue arrows) and glands (red arrows). Note NHERF1 labeling of glandular epithelial apical membrane and small T lymphocytes. The neoplastic cells show Cam 5.2 diffuse and strong cytoplasmic staining, synaptophysin and prolactin diffuse peripheral staining (insets with magnification), negative estrogen receptor (ER) staining, increased Ki-67 proliferation index and lack of p53 diffuse staining. E Timeline of tumor progression and treatment for the LFS M6 patient. Red rhomboid arrows indicate intracranial surgeries; green arrows (up – growth; down – decrease) indicate tumor progression observed on MRI (MRI progr); yrs, years; RT, radiotherapy (proton beam therapy); chemo, chemotherapy. F MRI of the two posterior fossa masses: left hemispheric cerebellar mass, and right dural mass (red arrow). G H&E and IHC with p53 antibody of the cerebellar mass show the large cell/anaplastic MB variant. H High-grade pleomorphic sarcoma shows numerous atypical mitotic figures (green arrowheads) and multinucleated osteoclast-like giant cells (blue arrows)