Chromosomal aberrations of M0 versus M+ non-WNT/non-SHH medulloblastomas
Introduction: Whole genome analysis of non-WNT/non-SHH medulloblastomas (MB) was performed to compare chromosomal aberrations between MB without metastases (M0) and metastatic MB (M+).
Methods: 57 M0 and 79 M+ MB were analyzed by molecular inversion profiling and whole chromosomal aberrations (WCA) were assessed.
Results: Chr. 7 gain (M0, 49%; M+, 37%) and chr. X loss (M0, 32%; M+, 22%) were the most frequent WCA in both groups. In both cohorts loss of chr. 11 was associated with favourable outcome (5-year PFS: M0, 100% (n = 13) vs. 71%; M+, 81% (n = 16) vs. 50%). Gain of chr. 7 and loss of chr. 8 were predictive for good outcome only in the M0 group (5-year PFS: 89% (n = 28) vs. 66% and 94% (n = 18) vs. 69%) while chr. 10 loss indicated a better outcome in M+ patients (5-year PFS: 100% (n = 7) vs. 53%). In the M0 cohort, the presence of any WCA was associated with a better outcome, but not in the M+ cohort.
Conclusion: Assessment of WCA can be used to identify prognostic chromosomal aberrations in non-WNT/non-SHH MB, but their predictive value differ between M0 and M+ patients.