Introduction: Craniopharyngiomas are usually benign intracranial tumours which can sometimes be locally aggressive. Malignant transformation is extremely rare and has a poor prognosis. We report a case of a patient who developed carcinomatous changes in a craniopharyngioma which was first excised almost 55 years ago.
Case report: Mr AM was diagnosed with a craniopharyngioma at the age of 5 years. He underwent surgery in 1952 but was lost to follow up and presented again in 1997. MRI at this time showed a large residual craniopharyngioma. He remained stable for several years but in 2001 his visual fields deteriorated and repeat MRI confirmed an increase in the size of the tumour. He underwent transsphenoidal excision of the craniopharyngioma followed by radiotherapy. Histology did not show any features suggesting malignancy.
Things remained stable until September 2008 when he started having severe headaches. MR scan showed a stable appearance of the tumour. However he then developed diplopia associated with a right sixth nerve palsy. MR scan demonstrated a significant increase in the solid component of the tumour. Further scans in February and March 2009 showed a rapid increase in tumour size with optic chiasmal compression, extension into the nasopharynx and left temporal lobe, and destruction of the skull base and clivus. Biopsy of the lesion confirmed this to be a recurrent adamantinomatous craniopharyngioma with foci of malignant transformation. As the tumour was not considered suitable for further surgery he received radiotherapy which resulted in some tumour shrinkage and improvement of his symptoms initially but later deteriorated and died in October 2009.
Discussion: Malignant transformation in adamantinomatous craniopharyngioma is relatively rare and is usually associated with previous multiple recurrences. The case we have reported demonstrates carcinomatous change in a patient who had previously followed a relatively stable course for over 50 years.