Department of Pathology, University of Oklahoma Health Sciences Center

NeuroTest Sample Question #47 Next question Previous question

Answer: A (Glial neoplasm)  Level of difficulty: 2 NeuroTest NeuroLearn NeuroHelp

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Discussion: 

• Pathology of the case: In Panel A, clusters of loosely arranged cells are present in the cytologic preparation. Even at low magnification, the nuclei appear triangular to irregular and pointy. Some very elongated cytoplasmic processes (Ý) can be seen. In Panel B, the nuclei appear hyperchromatic, elongated, irregular and pointy. There is general trend that the nucleus are quite distortable by the smearing process. No prominent nucleoli are present. The background is composed of a loosely knitted mesh of fine cytoplasmic processes (Ý). These features are quite characteristic for glial neoplams in general. The material of this case was obtained from a glioblastoma. [Click here to see the entire case]
• Lymphoma: Lymphoma typically smear out more homogeneously and appear more monotonous. They usually do not have the amphophilic long cytoplasmic processes as in glioma. However, it should be noted that the nuclei of lymphoma and other small cell neoplasm such as metastatic small cell carcinoma can easily be damaged and give elongated, purple to blue cytoplasmic process due to smearing of the nuclei acid. These process should not be confused with the elongated cytoplasmic processes in glial neoplasm. [Click here to see the cytology of a lymphoma]
• Metastatic carcinoma: regardless of the type, metastatic carcinoma tend to stay in clusters. Cytoplasmic vacuoles can be seen in metastatic adenocarcinoma but this is not a constant feature. However, the separation of metastatic small cell carcinoma from a cellular glioblastoma may be troublesome on cytologic preparation alone. The frozen section may provide valuable architectural information for the separation of the two. [Click here to see a cytologic preparation of metastatic renal cell carcinoma to the brain]
• Metastatic malignant melanoma: Distinction of metastatic malignant melanoma from metastatic carcinoma can be toublesome. However, distinction of metastatic malignant melanoma from glioblastoma and other glial neoplasm is easier. Malignant melanoma tend to be not as cohesive as carcinoma but the are not entirely segregated as in lymphoma. They tend to have a amphophic cytoplasm that carries a greyish hue. The nuclei are typically large, pleomorphic, and contain prominent nucleoli. Pseudonuclear inclusion are often present. When melanin pigment is present, they are very useful. Unfortunately, they are not that often seen in metastatic malignant melanoma.
• Meningioma: Meningiomatous cells tend to arrange in clusters and have well-defined cytoplasm on cytologic preparations. Pseudonuclear inclusions are also commonly seen in meningiomas.

Comment: KarMing-Fung@ouhsc.edu