抄録
We report a case of cystic lesion in the sella turcica to suprasellar region that was difficult to diagnose with pathological and histological examinations. A 67-year-old man presented chief complaint of visual acuity.Magnetic resonance imaging (MRI) revealed cystic lesion in the sella turcica to suprasellar region. The cystic lesion stretched the pituitary stalk. The cyst wall was partially resected under bifrontal craniotomy.As pathological finding, cyst wall had been covered with single layer of cubic epithelium and/or squamous epithelium, cilia were not recognized. In immunohistochemical study, cytokeratin AE1/AE3 and Cam5.2 were strongly positive in the epithelial cells of the cyst wall, however, s-100 positive cells in the epithelium were also present. Cells lining the cyst wall were suggested to possess neuro-epithelial component. Most cases of cystic lesion in the sella turcica to suprasellar region are Rathke’s cleft cyst, and histological diagnosis of the cyst can be easy. However, histological findings for Rathke’s cleft, colloid, epithelial, and ependymal cysts are similar, and some cases are difficult to diagnose. Rathke’s pouch is ectodermal in origin, and Rathke’s cleft cyst is what remains in the sella turcica during formation of the anterior and intermediate pituitary lobes in the embryonic period. It should be differentiated from endoderm-derived colloid, epithelial, and ependymal cysts. In the present case, in the benign cystic lesion in the sella turcica to suprasellar region, the parietal cells of the cystic lesion were cytokeratin positive in the histopathological findings. Thus, Rathke’s cleft cyst was suspected by imaging findings and intraoperative findings. However, the columnar epithelium and cilium were unclear. As S-100 positive cells were disseminated, neuroepithelial cells were also suspected. Thus, a definite diagnosis of Rathke’s cleft cyst could not be made. If a histologically definitive diagnosis could not be made, it is considered necessary to first diagnose the lesion as a benign cystic lesion, record the diagnosis as histologically presumed, and then attempt a comprehensive diagnosis in combination with imaging findings.
