Which of the following are histological features of medulloblastoma as shown in the diagram?
**Core Concept**
Medulloblastoma is a highly malignant primary brain tumor in children, characterized by its rapid growth and potential for metastasis. The histological features of medulloblastoma are crucial for its diagnosis and differentiation from other brain tumors.
**Why the Correct Answer is Right**
Medulloblastoma is a type of embryonal tumor that typically exhibits a characteristic histological pattern. The correct answer features a "small, round, blue cell" morphology with a high nuclear-to-cytoplasmic ratio, a hallmark of neuroblastic differentiation. This is due to the presence of primitive neuroectodermal cells that express neural markers such as synaptophysin and neurofilament. The tumor cells often exhibit Homer Wright rosettes, which are circular arrangements of cells surrounding a central cavity, and a high mitotic index.
**Why Each Wrong Option is Incorrect**
**Option A:** This option shows a tumor with a more differentiated appearance, featuring large, pleomorphic cells with abundant cytoplasm, which is not characteristic of medulloblastoma.
**Option B:** This option depicts a tumor with a prominent glial component, which is not typical of medulloblastoma. Medulloblastoma is a neuroepithelial tumor, not a glioma.
**Option C:** This option shows a tumor with a prominent vascular component, which is not a characteristic feature of medulloblastoma. While medulloblastoma can exhibit some vascular proliferation, it is not a defining feature.
**Option D:** This option shows a tumor with a more mature appearance, featuring large, polygonal cells with abundant cytoplasm, which is not characteristic of medulloblastoma.
**Clinical Pearl / High-Yield Fact**
Medulloblastoma is a highly malignant tumor with a high propensity for metastasis, particularly to the cerebellum and spinal cord. Early diagnosis and treatment are crucial for improving patient outcomes.
**Correct Answer:** C