Concomitant intraventricular colloid cyst and low-grade astrocytoma of the brainstem in a 16-year-old boy.

Multiple primary brain tumors are commonly observed in patients with a history of brain radiation therapy or neurofibromatosis. The concomitant presence of 2 different types of brain tumors in a single location or chamber is a very rare clinical presentation in the absence of such a predisposing factor. The authors report on the case of a 16-year-old boy presenting with different types of brain tumors in 2 ventricular chambers concomitantly. This boy had a medium-sized colloid cyst of the third ventricle and a large fibrillary astrocytoma fungating from the brainstem into the floor of the fourth ventricle. The lesions were successfully excised in 2 separate surgeries. Radiotherapy was used as the adjuvant mode of therapy. There has been no sign of tumor recurrence after 16 months of follow-up. Clinical awareness and recognition of such a combination of tumors is important because they will dictate special treatment strategies depending on the individual biological aggressiveness of each tumor.