Medulloblastoma in childhood-King Edward Memorial hospital surgical experience and review: Comparative analysis of the case series of 365 patients

AIM: Medulloblastoma is one of the most common posterior fossa tumors in childhood. The treatment-related side effects as well as predictive outcome still remain as a major challenge. The improved understanding of the disease and advances in molecular biology is changing the treatment paradigms from Chang's staging system to molecular risk stratification. However, surgery still remains as an important mainstay of therapy and is formidable. The role of radical surgery has always been a crucial factor in the outcome of these patients, the best survival being reported in patients who had total excision of the tumor and with no metastasis. PATIENT AND METHODS: An analysis of 365 patients (age<18 years) of medulloblastoma who underwent treatment at the Seth G.S. Medical College and King Edward VII Memorial hospital (KEM), Mumbai over a 25- year period (1985-2000 and 2001-2010) is presented. The clinical profile, radiological features, pathology and surgical nuances are discussed. RESULTS: The most common age group affected was between 3 and 12 years. 75.3% presented with headaches, vomiting and 63.2% with papilledema. Sitting position was used in majority of cases. A total of 8 patients underwent shunting; all of them were in the postoperative period (5.19%). 92.2% (142 cases) had classical medulloblastoma, 5.1% (8 cases) had desmoplastic variant, 1.9% (3 cases) had anaplastic changes and 0.6% (1 case) had glial differentiation. The 5-year and 10-year progression free survival rate was 73 and 41% for average risk disease while for high risk disease rate it was 34%. The mortality rate was 2%. The quality of life was enhanced in patients who survived 5-10 years after treatment. CONCLUSION: Surgery for medulloblastoma is formidable. The option of sitting position for medulloblastoma surgery is still viable. A vigilant neuroanesthesiologist and a safe surgery are necessary to achieve a good postoperative result. Radiological characteristics are helpful adjuncts for determining effective surgical strategy. Permanent CSF drainage can be avoided in majority of patients and can be definitively considered in progressive symptomatic hydrocephalus. A safe maximal resection and a good Karnofsky score are paramount to ensure compliance with adjuvant therapy and contribute to an overall survival advantage.