Malignant Craniopharyngioma With Features Resembling Ghost Cell Odontogenic Carcinoma: A Case Report and Histopathology Literature Review.

Malignant transformation of craniopharyngioma is an exceptionally rare and poorly characterized phenomenon. We report a case of a 15-year-old girl who developed symptom recurrence 9 years after undergoing surgery and radiotherapy for adamantinomatous craniopharyngioma. Histology revealed malignant areas comprising highly proliferative basaloid cells with abrupt transitions into ghost cells, resembling ghost cell odontogenic carcinoma. We conducted a literature review and pooled case analysis of 45 cases, which showed a median benign-to-malignant latency of 10 years and a median overall survival of 9 months. The majority of benign diagnoses were adamantinomatous type. Prior radiotherapy was noted in 27 cases (60%). Histological findings of malignant components were reported as unspecified malignant transformation in 20 cases (44.4%), squamous cell carcinoma (SCC) in 16 cases (35.6%), odontogenic-type carcinomas in 5 cases (11.1%), and other types in 4 cases (8.9%). Immunohistochemical analyses showed consistent positivity for pan-cytokeratin, p63, and p40 in all cases performed. The p53 and Ki-67 also consistently exhibited increased or abnormal expression. Due to the overlapping histological and immunohistochemical features of odontogenic-type carcinomas and SCC, careful assessment is recommended when diagnosing recurrent CPs.