Postoperatively, children may have significant neurologic deficits caused by preoperative tumor-related brain injury, hydrocephalus, or surgery-related brain injury.[Level of evidence: 3iC] In addition, a significant number of patients with medulloblastoma will develop delayed onset of mutism, suprabulbar palsies, ataxia, hypotonia, and emotional lability. This constellation of findings has been termed the cerebellar mutism syndrome, and its etiology remains unclear, although cerebellar vermian damage has been postulated as a possible cause for the mutism.[11,12]; [Level of evidence: 3iC] In two Children's Cancer Group studies evaluating children with both average-risk and poor-risk medulloblastoma, the syndrome has been identified in nearly 25% of patients.[12,13,14]; [Level of evidence: 3iiiC] Many patients with this syndrome may manifest neurologic and neurocognitive sequelae posttreatment.[13,15]
Radiation therapy is usually initiated after surgery with or without concomitant chemotherapy.[16,17,18] To date, the best survival results for children with medulloblastoma have been obtained when radiation therapy is begun within 4 to 6 weeks postsurgery.[16,17,18,19]; [Level of evidence: 1iA]
Prospective randomized trials and single-arm trials suggest that adjuvant chemotherapy given during and after radiation therapy improves overall survival for children with both average-risk and poor-risk medulloblastoma.[15,16,17,18,19,20] Although medulloblastoma is often sensitive to chemotherapy, preradiation chemotherapy has not been shown to improve survival compared with treatment with radiation therapy and subsequent chemotherapy. In some prospective studies, preradiation chemotherapy has been related to a poorer rate of survival.[17,18,19,20]
Children of all ages are susceptible to the adverse effects of radiation on brain development. Debilitating effects on growth and neurologic/cognitive development have been frequently observed, especially in younger children.[21,22,23,24] For this reason, the role of chemotherapy in allowing a delay in the administration of radiation therapy has been and is being studied. Results suggest that chemotherapy can be used to delay and sometimes obviate the need for radiation therapy in 20% to 40% of children younger than 3 years with nondisseminated medulloblastoma.[25,26]; [Level of evidence: 3iiiC] Children are also at risk for long-term endocrine dysfunction.
Surveillance testing is a part of all ongoing medulloblastoma studies.[28,29,30] Although most treatment failures in patients newly diagnosed with medulloblastoma will occur within the first 18 months postdiagnosis, relapses many years after diagnosis have been noted. In addition, secondary tumors have been increasingly diagnosed in long-term survivors.[30,31]; [Level of evidence: 2A] As with initial management, long-term management is complex and requires a multidisciplinary approach.
- Dubuc AM, Northcott PA, Mack S, et al.: The genetics of pediatric brain tumors. Curr Neurol Neurosci Rep 10 (3): 215-23, 2010.
- Zeltzer PM, Boyett JM, Finlay JL, et al.: Metastasis stage, adjuvant treatment, and residual tumor are prognostic factors for medulloblastoma in children: conclusions from the Children's Cancer Group 921 randomized phase III study. J Clin Oncol 17 (3): 832-45, 1999.
- Northcott PA, Korshunov A, Witt H, et al.: Medulloblastoma comprises four distinct molecular variants. J Clin Oncol 29 (11): 1408-14, 2011.
- Ellison DW, Dalton J, Kocak M, et al.: Medulloblastoma: clinicopathological correlates of SHH, WNT, and non-SHH/WNT molecular subgroups. Acta Neuropathol 121 (3): 381-96, 2011.
- Cho YJ, Tsherniak A, Tamayo P, et al.: Integrative genomic analysis of medulloblastoma identifies a molecular subgroup that drives poor clinical outcome. J Clin Oncol 29 (11): 1424-30, 2011.
- Ellison DW, Kocak M, Dalton J, et al.: Definition of disease-risk stratification groups in childhood medulloblastoma using combined clinical, pathologic, and molecular variables. J Clin Oncol 29 (11): 1400-7, 2011.
- Albright AL, Wisoff JH, Zeltzer PM, et al.: Effects of medulloblastoma resections on outcome in children: a report from the Children's Cancer Group. Neurosurgery 38 (2): 265-71, 1996.
- Taylor RE, Bailey CC, Robinson K, et al.: Results of a randomized study of preradiation chemotherapy versus radiotherapy alone for nonmetastatic medulloblastoma: The International Society of Paediatric Oncology/United Kingdom Children's Cancer Study Group PNET-3 Study. J Clin Oncol 21 (8): 1581-91, 2003.
- Grill J, Lellouch-Tubiana A, Elouahdani S, et al.: Preoperative chemotherapy in children with high-risk medulloblastomas: a feasibility study. J Neurosurg 103 (4 Suppl): 312-8, 2005.
- Stargatt R, Rosenfeld JV, Maixner W, et al.: Multiple factors contribute to neuropsychological outcome in children with posterior fossa tumors. Dev Neuropsychol 32 (2): 729-48, 2007.
- Pollack IF, Polinko P, Albright AL, et al.: Mutism and pseudobulbar symptoms after resection of posterior fossa tumors in children: incidence and pathophysiology. Neurosurgery 37 (5): 885-93, 1995.
- Robertson PL, Muraszko KM, Holmes EJ, et al.: Incidence and severity of postoperative cerebellar mutism syndrome in children with medulloblastoma: a prospective study by the Children's Oncology Group. J Neurosurg 105 (6): 444-51, 2006.
- Wells EM, Khademian ZP, Walsh KS, et al.: Postoperative cerebellar mutism syndrome following treatment of medulloblastoma: neuroradiographic features and origin. J Neurosurg Pediatr 5 (4): 329-34, 2010.
- Gudrunardottir T, Sehested A, Juhler M, et al.: Cerebellar mutism: review of the literature. Childs Nerv Syst 27 (3): 355-63, 2011.
- Wolfe-Christensen C, Mullins LL, Scott JG, et al.: Persistent psychosocial problems in children who develop posterior fossa syndrome after medulloblastoma resection. Pediatr Blood Cancer 49 (5): 723-6, 2007.
- Packer RJ, Sutton LN, Elterman R, et al.: Outcome for children with medulloblastoma treated with radiation and cisplatin, CCNU, and vincristine chemotherapy. J Neurosurg 81 (5): 690-8, 1994.
- Bailey CC, Gnekow A, Wellek S, et al.: Prospective randomised trial of chemotherapy given before radiotherapy in childhood medulloblastoma. International Society of Paediatric Oncology (SIOP) and the (German) Society of Paediatric Oncology (GPO): SIOP II. Med Pediatr Oncol 25 (3): 166-78, 1995.
- Kortmann RD, Kühl J, Timmermann B, et al.: Postoperative neoadjuvant chemotherapy before radiotherapy as compared to immediate radiotherapy followed by maintenance chemotherapy in the treatment of medulloblastoma in childhood: results of the German prospective randomized trial HIT '91. Int J Radiat Oncol Biol Phys 46 (2): 269-79, 2000.
- Taylor RE, Bailey CC, Robinson KJ, et al.: Impact of radiotherapy parameters on outcome in the International Society of Paediatric Oncology/United Kingdom Children's Cancer Study Group PNET-3 study of preradiotherapy chemotherapy for M0-M1 medulloblastoma. Int J Radiat Oncol Biol Phys 58 (4): 1184-93, 2004.
- von Hoff K, Hinkes B, Gerber NU, et al.: Long-term outcome and clinical prognostic factors in children with medulloblastoma treated in the prospective randomised multicentre trial HIT'91. Eur J Cancer 45 (7): 1209-17, 2009.
- Ris MD, Packer R, Goldwein J, et al.: Intellectual outcome after reduced-dose radiation therapy plus adjuvant chemotherapy for medulloblastoma: a Children's Cancer Group study. J Clin Oncol 19 (15): 3470-6, 2001.
- Packer RJ, Sutton LN, Atkins TE, et al.: A prospective study of cognitive function in children receiving whole-brain radiotherapy and chemotherapy: 2-year results. J Neurosurg 70 (5): 707-13, 1989.
- Johnson DL, McCabe MA, Nicholson HS, et al.: Quality of long-term survival in young children with medulloblastoma. J Neurosurg 80 (6): 1004-10, 1994.
- Walter AW, Mulhern RK, Gajjar A, et al.: Survival and neurodevelopmental outcome of young children with medulloblastoma at St Jude Children's Research Hospital. J Clin Oncol 17 (12): 3720-8, 1999.
- Geyer JR, Sposto R, Jennings M, et al.: Multiagent chemotherapy and deferred radiotherapy in infants with malignant brain tumors: a report from the Children's Cancer Group. J Clin Oncol 23 (30): 7621-31, 2005.
- Chi SN, Gardner SL, Levy AS, et al.: Feasibility and response to induction chemotherapy intensified with high-dose methotrexate for young children with newly diagnosed high-risk disseminated medulloblastoma. J Clin Oncol 22 (24): 4881-7, 2004.
- Laughton SJ, Merchant TE, Sklar CA, et al.: Endocrine outcomes for children with embryonal brain tumors after risk-adapted craniospinal and conformal primary-site irradiation and high-dose chemotherapy with stem-cell rescue on the SJMB-96 trial. J Clin Oncol 26 (7): 1112-8, 2008.
- Saunders DE, Hayward RD, Phipps KP, et al.: Surveillance neuroimaging of intracranial medulloblastoma in children: how effective, how often, and for how long? J Neurosurg 99 (2): 280-6, 2003.
- Jenkin D: Long-term survival of children with brain tumors. Oncology (Huntingt) 10 (5): 715-9; discussion 720, 722, 728, 1996.
- Goldstein AM, Yuen J, Tucker MA: Second cancers after medulloblastoma: population-based results from the United States and Sweden. Cancer Causes Control 8 (6): 865-71, 1997.
- Stavrou T, Bromley CM, Nicholson HS, et al.: Prognostic factors and secondary malignancies in childhood medulloblastoma. J Pediatr Hematol Oncol 23 (7): 431-6, 2001.
- Allen J, Donahue B, Mehta M, et al.: A phase II study of preradiotherapy chemotherapy followed by hyperfractionated radiotherapy for newly diagnosed high-risk medulloblastoma/primitive neuroectodermal tumor: a report from the Children's Oncology Group (CCG 9931). Int J Radiat Oncol Biol Phys 74 (4): 1006-11, 2009.