The Spectrum of Malignancy in Craniopharyngioma

Abstract

Craniopharyngiomas are low-grade epithelial neoplasms occurring almost exclusively in the sellar/suprasellar region. Histologic malignancy is extremely rare; the literature consists mostly of isolated case reports. Herein, we report 3 patients with craniopharyngiomas exhibiting histologic malignancy, 2 of which received radiation therapy before its appearance. Hematoxylin and eosin-stained slides and selected immunohistochemical stains were reviewed in all cases. Microvessel density analysis was performed in case 2. The patients included 2 men and 1 woman, age 14, 31, and 58 years at presentation, respectively. All patients expired 3 months to 9 years after first resection and 3 to 9 months after identification of histologic malignancy. The latter developed after multiple recurrences and radiation therapy in 2 cases, but seemed to arise de novo in 1 case resembling odontogenic ghost cell carcinoma and lacking any definite low-grade craniopharyngioma precursor. The malignant component of the other 2 cases resembled squamous cell carcinoma and low-grade myoepithelial carcinoma, respectively. The MIB-1 labeling index was markedly increased in the malignant component in comparison with the low-grade precursor. Malignant transformation in craniopharyngiomas, although rare, does exist. It assumes varied histologic appearances, usually after multiple recurrences and radiation therapy, and has a near uniformly fatal outcome. De novo malignancy in odontogenic tumors of the sella is even more unusual, but also has an ominous prognosis.

Malignant Transformation of Craniopharyngioma Associated With Moyamoya Syndrome -Case Report-

“…This immunohistochemical finding may be an effective surrogate marker of malignant transformation. 3,7,17,18) Positive immunostaining for p63, a homologue of p53 protein, was also observed in the present case, although this issue remains to be elucidated.…”

“…De novo tumor is histologically similar to odontogenic tumors, so that the tumor is an odontogenic ghost cell carcinoma. 18) Other de novo tumors contain components of adamantinomatous craniopharyngioma. 3,24) The current case presented similar diagnostic problems.…”

“…3,18,24) Such tumors should possibly be considered as a World Health Organization grade 3 tumor, a new variant of malignant craniopharyngioma, 3,10) although whether the tumors are derived from the remnant of Rathke's pouch is debatable. De novo tumor is histologically similar to odontogenic tumors, so that the tumor is an odontogenic ghost cell carcinoma.…”

“…1,3,7,14,17,18,20,23,24) The patients were aged 11 to 62 years (median 31 years), and the male to female ratio is 6:7. Radiotherapy was administered in all but the three patients with de novo tumor, and may have been one of the causes of the subsequent malignant transformation.…”

“…Almost all craniopharyngiomas have benign features, and histologically malignant craniopharyngiomas are extremely rare. 1,3,7,14,17,18,20,23,24) Moyamoya disease is an idiopathic disease entity characterized by progressive intracranial occlusion of the anterior circulation followed by the appearance of an abnormal collateral vascular network around the circle of Willis. 15,21) Moyamoya vessels may also arise in patients with predisposed disorders such as parasellar tumors and cranial irradiation, 10,13) which is known as moyamoya syndrome, quasi moyamoya disease, akin moyamoya disease, and moyamoya-like vasculopathy.…”