Long-term outcomes and role of chemotherapy in adults with newly diagnosed medulloblastoma

Abstract

Objective: To assess the survival and role of adjuvant chemotherapy in adult medulloblastoma.

Methods: We reviewed outcomes of 66 patients (aged 18 y or more; median age, 33 y) with medulloblastoma. Forty-four (67%) patients had M0 disease, 9 had M1-M4, and 13 had MX. Thirty-one patients each for whom risk stratification was available were classified as high risk or standard risk. Fifty-six patients had histologic results: classic histology was the most common (n=46 [84%]), followed by desmoplastic (n=9), and large cell/anaplastic (n=1). Overall survival (OS) and progression-free survival (PFS) were estimated with Kaplan-Meier curves and log-rank tests. Cox regression analysis was used to compare recurrences.

Results: Median follow-up was 6.7 years. The estimated 5-year OS and PFS were 74% and 59%, respectively. High-risk versus standard-risk classification was associated with worse OS (61% vs. 86%; P=0.03) and recurrence (hazard ratio, 2.56; P=0.05) and a trend for worse PFS (49% vs. 69%; P=0.13). Gross total resection was associated with improved OS (P=0.03) and a trend toward improved PFS (P=0.09). No chemotherapy benefit could be demonstrated for the group as a whole. For high-risk patients with classic histology (n=25), chemotherapy was associated with a trend for improvement in 5-year PFS from 36% to 71% (P=0.10) and in 5-year OS from 49% to 100% (P=0.08).

Conclusions: In adult patients with medulloblastoma, the extent of resection and risk classification predicts the outcome. These results suggest a chemotherapy benefit for high-risk patients with classic histology.

FIGURE 1

Survival after diagnosis of medulloblastoma. Kaplan-Meier estimates of progression-free survival (PFS) and overall survival (OS) for 66 adult patients from the time of diagnosis.

FIGURE 2

Progression-free survival (PFS) of adult medulloblastoma patients by risk group. Kaplan-Meier estimates of PFS for 31 standard-risk adult patients compared with that for 31 high-risk patients (P = 0.13).

FIGURE 3

Overall survival (OS) of adult medulloblastoma patients by risk group. Kaplan-Meier estimates of OS for 31 standard-risk patients compared with that for 31 high-risk patients (P = 0.03).

FIGURE 4

Effects of chemotherapy in select subgroups of adult medulloblastoma patients. A and B, Kaplan-Meier estimates for progression-free survival (PFS) (P = 0.46) and overall survival (OS) (P = 0.36) for 31 high-risk patients treated with or without chemotherapy. C and D, Kaplan-Meier estimates for PFS (P = 0.10) and OS (P = 0.08) with both high-risk and classic histology (n = 25) with (n = 14) or without (n = 11) chemotherapy. Chemo indicates chemotherapy; No chemo, no chemotherapy.

FIGURE 5

Overall survival (OS) of adult medulloblastoma patients by time period treated. No significant difference in OS was found among groups of patients treated in 1969 to 1979, 1980 to 1989, 1990 to 1999, or 2000 to 2008 (P = 0.65).

FIGURE 6

Overall survival of adult medulloblastoma patients staged with or without magnetic resonance imaging (MRI). No significant difference was demonstrated for medulloblastoma patients staged with MRI (n = 44) over those not staged with MRI (n = 22) (P = 0.46).