Cystic dissemination of choroid plexus papilloma: illustrative cases

Abstract

Background: Choroid plexus papillomas are benign tumors of the choroid plexus. Although typically focal, they can metastasize. Rarely, patients may present with numerous cystic lesions throughout the craniospinal axis.

Observations: The authors present three cases of pathologically confirmed fourth ventricular World Health Organization (WHO) grade 1 choroid plexus papillomas presenting with numerous cystic lesions throughout the craniospinal axis. Two cases were treated with only resection of the fourth ventricular mass; one was treated with a partial cyst fenestration. During follow-up, there was only mild interval growth of the cystic lesions over time, and all patients remained asymptomatic from their cystic lesions. The authors summarize five additional cases of cystic dissemination in the published literature and discuss hypotheses for the pathophysiology of this rare presentation.

Lessons: Choroid plexus papillomas may present with numerous, widely disseminated cystic lesions within the craniospinal axis. Thus, the authors recommend preoperative and routine imaging of the entire neuroaxis in patients with choroid plexus tumors, regardless of WHO grade. Although the role of adjuvant therapy and cyst fenestration in the treatment of these lesions remains unclear, watchful waiting may be indicated, especially in asymptomatic patients, because the lesions often demonstrate slow, if any, growth over time.

Keywords: choroid plexus papilloma; choroid plexus tumor; cystic dissemination; dissemination.

FIG. 1.

Case 1. A 40-year-old female with headaches was found to have a fourth ventricular lesion and multiple cystic lesions. A: Sagittal postcontrast T1-weighted MRI shows mildly enhancing fourth ventricular CPP. B: Axial postcontrast T1-weighted MRI shows nonenhancing cystic lesions (arrows). C: Sagittal T2-weighted MRI of the thoracic spine shows a cystic lesion at T8 (circle). D: Axial T2-weighted MRI at T8 shows a cystic lesion (arrow). E: Sagittal T2-weighted MRI of the lumbar spine shows a cystic lesion at L2 (circle). F: Axial T2-weighted MRI at L2 shows a cystic lesion (arrow).

FIG. 2.

Case 2. An 11-year-old female with fourth ventricular CPP and multiple cystic lesions. A: Sagittal postcontrast T1-weighted MRI shows a large enhancing fourth ventricular lesion. B: Axial postcontrast T1-weighted MRI shows a fourth ventricular lesion. C: Axial T2-weighted MRI shows multiple cystic lesions (arrows). Axial T1-weighted (D) and T2-weighted (E) MRI shows multiple hypodense cystic lesions (arrows) 3 years after resection of the fourth ventricular tumor. F: Sagittal T2-weighted MRI of the cervical spine shows multiple hyperintense cystic lesions (arrows) 8 years after resection of the fourth ventricular tumor.

FIG. 3.

Case 3. A 24-year-old male with multiple cystic lesions. A: Sagittal postcontrast T1-weighted MRI shows heterogeneously enhancing fourth ventricular CPP. B: Axial postcontrast T1-weighted MRI showing fourth ventricular lesion and multiple hypodense cystic metastases. C: Axial T2-weighted MRI shows multiple cystic metastases. Axial T1-weighted (D) and T2-weighted (E) MRI shows large cyst (arrows) before cyst fenestration. F: Axial T2-weighted MRI shows interval increase in the size of the anterior fossa cystic lesion (arrow) after 2 years. G and H: Axial T2-weighted MRI shows multiple small cystic lesions (arrows) 9 years before resection of the patient’s fourth ventricular tumor.