Department of Pathology, University of Oklahoma Health Sciences Center

NeuroTest Sample Question #59 Next question Previous question

Answer: D (Metastatic small cell carcinoma, primitive neuroectodermal tumor, and glioblastoma are all possible)  Level of difficulty: 3 NeuroTest NeuroLearn NeuroHelp

Discussion: 

• Pathology of the case: The background is necrotic and many pyknotic nuclei are present (Þ). The nuclei appear to have a dirty "salt and pepper" chromatin and there is some variation in nuclear size. The amount of cytoplasm is minimal to small. These features are highly suggestive of a metastatic small cell carcinoma. In fact, this specimen was obtained from a metastatic small cell carcinoma. It should be noted that the nuclei of small cell carcinoma may not look "small" in cytoloogic preparation. If you compare this photo with the pituitary adenoma that is illustrated in question #58, you can appreciate the variationin size of the nuclei [Click here to see question #58].
• Primitive neuroectodermal tumor (PNET): This is the less likely diagnosis although possible. PNET usually are not as necrotic as illustrated here. The age is also not uncommon.
• Glioblastoma: This diagnosis is more likely than PNET in this case. The old name of glioblastoma multiforme reflects the possible diversification of this tumor. Although the cytologic features being shown here is uncommon for a glioblastoma, it is far from rare in my opinion.

Comment: KarMing-Fung@ouhsc.edu