Choroid plexus papilloma of the cerebellopontine angle: a twelve patient series

Choroid plexus papillomas (CPPs), of the cerebellopontine angle (CPA), are a rare entity and no surgical series have been reported so far. We reviewed all the pertinent literature of 12 patients operated on in the last 20 years at our institution.

All the patients were adults, ranging from 19 to 61 years. The group included 6 males and 6 females. Preoperatively, on computerized tomography (CT) (n = 10) or magnetic resonance imaging (MRI) (n = 4), differential diagnosis was difficult to achieve, especially with meningiomas. Hydrocephalus was disclosed in 8 cases. Angiography (n = 11) showed tumor blush with typical vascular supply in almost half the cases.

In 6 patients a midline approach via the cerebellomedullary fissure was used; in the remaining 6 patients the retromastoid route was adopted. We found 2 "unconnected" tumors; no hilum was identified at surgery. Total tumor removal was achieved in 6 patients, predominantly in the last cases. Two patients died in the postoperative period, 3 patients had mild additional deficits, whereas 7 patients were stable or improved. All the patients were followed up for a mean period of 8.2 years. Conventional radiotherapy was carried out in 5 patients; 1 of them after tumor recurrence. Stereotactic radiotherapy was performed in 3 patients; 2 of them after recurrences. Two patients showed tumor progression and died during the follow-up. One of them presented a suprasellar metastasis and died much earlier (2 versus 7 years).

Careful assessment and surgical planning is accomplished with the combined information from CT, MRI, and angiography. Typical characteristics are the following: vascular supply from the choroidal arteries, ventral extension, adhesion to the brainstem, and lower cranial nerves. Nowadays, total removal of CPPs of the CPA can be achieved with acceptable morbidity and mortality. In our experience, conventional radiotherapy did not prove effective.