Diagnosis and treatment of cerebellopontine angel medulloblastoma

Abstract:

Objective：To analyze the clinical，imaging and pathological characteristics of cerebellopontine angel（CPA） medulloblas－toma. Methods：Clinical manifestations，imaging characteristics，pathological types and surgical outcomes of eight patients with CPA medulloblastoma were retrospectively analyzed，and their tumors were underwent the molecular grouping and assessment. Results：Patients had an age from 7 to 52 years old，with the most frequent symptoms of intracranial pressure，cerebellar signs，decreased hearing，facial paralysis and abducent nerve paralysis. MRI demonstrated a solid CPA lesion，with mild to moderate enhancement，accompanying with peritumoral oedema，cystic change and dural tail sign，while CT showed no damage and hyperplasia of petrous bone and internal auditory canal intact. Among eight patients，six patients underwent total resection and the other two patients had partial excision. Postoperative pathological examination confirmed five cases of classic type，two cases of desmoplastic type and one case of anaplastic type. Further molecular analysis showed that five cases were WNT subtypes and three cases were SHH subtypes. After the surgery，symptoms and signs of seven patients immediately improved，and condition of one patient remained as the preopera－tive one. Follow-up was ranged from 5-34 months，during which five cases kept symptom free and three cases recurred/progressed. Conclusion：CPA medulloblastoma is rare and lacks special clinical manifestations and imaging features，which needs more attention on differentiating and diagnosing CPA disease. The most common pathological types and molecular subtypes are classical type and WNT subtypes，respectively. Microsurgery is an effective method to prevent the further deterioration of nerve function.