Ectopic recurrence of craniopharyngioma in the posterior fossa: Case report and review of the literature

Craniopharyngiomas are benign epithelial tumors which may very occasionally recur in ectopic locations. We present two cases of ectopic recurrence, both in the posterior fossa, and provide a review of the literature with basic statistics. Two patients admitted to our institution with posterior fossa lesions underwent gross total resection. Pathological studies showed adamantinomatous craniopharyngiomas (ACP). Both patients had a prior history of suprasellar tumor surgery. We also reviewed the related data and undertook a basic statistical analysis. We found 67 cases of ectopic recurrent craniopharyngioma (including the present cases): 51 cases were adamantinomatous (76%), 6 papillary (9%) and 10 unknown (15%). 18 cases occurred in the posterior fossa, all of them diagnosed as the ACP subtype. The intervals until recurrence were 15.15 years for posterior fossa recurrences and 5.75 years for supratentorial cases. Student t test showed significant differences in time to recurrence (p 0.002). Gross total resection was performed in 53 cases (79%), subtotal resection + radiotherapy in 3 (5%) and 11 (16%) cases were treated with other options. Ectopic recurrence is a rare but possible event. Those in the posterior fossa may appear later than in the supratentorial space. ACP is likely to be the most common subtype in these cases, possibly due to its more aggressive behavior compared to the papillary subtype. Long term follow-up should be performed to detect ectopic recurrences. Ectopic recurrences are often surgically accessible and gross total resection should be achieved.