title: Medulloblastoma with brain stem involvement: the impact of gross total resection on outcome.
abstract: We studied the impact of gross total resection on progression-free survival (PFS) and postoperative morbidity in 40 children with locally advanced medulloblastoma characterized by tumor invading the brain stem. These patients represented 40% of children treated for newly diagnosed medulloblastoma at a pediatric oncology center over a 10-year period. All patients underwent aggressive initial surgical resection. Review of surgical and neuroimaging findings documented gross total resection in 13 cases, near-total resection (< 1.5 cm2 residual tumor on imaging) in 14 cases, and subtotal resection (> than 50% resection with > or = 1.5 cm2 residual) in 13 cases. Overall, 85% of patients had a > 90% resection. Subsequent therapy comprised craniospinal irradiation in all cases and chemotherapy on institutional or cooperative group protocols in 35 cases. At a median follow-up of 4 years, postirradiation PFS is 61% (SE = 10%). There was no difference in PFS for patients who underwent gross total resection compared to those with any detectable residual tumor (p > 0.70). The posterior fossa syndrome occurred in 25% of cases, and had no apparent relationship to the extent of resection (p > 0.5, exact test). In this series, true gross total resection was not associated with a PFS advantage when compared to strictly defined near-total and subtotal resection. Although there was no operative mortality, the frequency of the posterior fossa syndrome is of concern and emphasizes the need for careful consideration of the risk/benefit ratio in the surgical approach to this subgroup of patients.
authors.affiliation: Le Bonheur Children's Medical Center, Brain Tumor Team, Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, TN 38101-0318, USA. amar.gajjar@stjude.org
authors.forename: A
authors.initials: A
authors.lastname: Gajjar
authors.forename: R A
authors.initials: RA
authors.lastname: Sanford
authors.forename: R
authors.initials: R
authors.lastname: Bhargava
authors.forename: R
authors.initials: R
authors.lastname: Heideman
authors.forename: A
authors.initials: A
authors.lastname: Walter
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: J W
authors.initials: JW
authors.lastname: Langston
authors.forename: J J
authors.initials: JJ
authors.lastname: Jenkins
authors.forename: M
authors.initials: M
authors.lastname: Muhlbauer
authors.forename: J
authors.initials: J
authors.lastname: Boyett
authors.forename: L E
authors.initials: LE
authors.lastname: Kun
mesh_terms: D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D001933:Brain Stem / Q000473:pathology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D003388:Cranial Fossa, Posterior / Q000473:pathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008527:Medulloblastoma / Q000401:mortality / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D015996:Survival Rate