Homer wright rossette are seen in-a) Neuroblastomab) Astrocytomac) Meningiomad) Pinealoma

Rosettes Rosettes are pathological findings characterized by a halo or spoke wheel arrangement of cells surrounding a central core or hub. Type of Rosette 1. Flexner - Wintersteiner Rosettes A halo of cells surrounds a largely empty central hub but small cytoplasmic extension from cells project into the lumen. It is characteristic of retinoblastoma. May also be seen in → Medulloblastoma, Primitive neuroectodermal tumor, Pineoblastoma. 2. Homer Wright rosettes A halo of cells surrounds a central hub that contains a meshwork of fibres (neutrophil rich centre). Homer-Wright rosettes are characteristic of neuroblastomas and medulloblastomas. May also be seen in → Primitive neuroectodermal tumors (PNET), Pineoblastomas, Retinoblastomas. 3. True ependymal Rosette A halo of cells surrounds an empty lumen. It is characteristic of ependymomas. 4. Perivascular pseudorosettes A halo of cells surrounds a blood vessel. The term pseudo is used because the central structure is not formed from the tumor itself, and represents a nonneoplastic element. May be seen in Ependymonas Glioblastomas Medulloblastomas Retinoblastoma Primitive neuroectodermal tumors    Monimorphous pilimyxoid astrocytoma Central neurocytoma