Clinical and pathologic features of malignant craniopharyngioma of the right thalamus

Ojbective: To report a case of craniopharyngioma of malignant transition in the right thalamencehpalon after the radiotherapy and discuss the mechanism of this change.Methods: We reviewed the clinical features and MRI.The specimen of the resected tissue was examined using routeine tissue slices with hematoxylin and eosin staining.Immunostaining was performed to detect the expression of p53 and Ki-67.Results: The tumors of the two times were in the same anatomic site.The tissue section submitted from the previous resections in 2000 for histologic examination were reviewed.We could see the majority of the tumor was keratinization and some benign squamous epithelium and there was no ameloblast component in all the section.But in the 2007 section,There were typical areas of squamous cell carcinoma and the transition from the benign squamous epithelium to the squamous cell carcinoma.Conclusion: Malignant craniopharyngiomas are distinctly rare tumors.We believe that the cause of malignant change in this case is the radiotherapy,but the relationship between malignant change and radiotherapy is still need more cases to be confirmed.