Fig. 4.

Comparison between intracranial GCTs (IGCTs) and testicular GCTs (TGCTs). (A) The percentage of germinoma and seminoma in each category was similar; however, the rates of nongerminomatous GCTs (NGGCTs) and nonseminomatous GCTs (NSGCTs) were different (26% vs. 40%, P = .04). Yolk sac tumor (YST) and embryonal carcinoma (EC) are more frequently found in TGCTs. (B) The presence of MAPK pathway mutations is similar in both IGCT and TGCT. (C) Copy number alterations were more prominent in TGCT. Statistically different frequencies of copy number alterations between IGCT and TGCT included a gain of chromosomes 7, 8, 12p, and loss of chromosomes 4,5,10,11,13,18. (D) Using the top 5000 probes of standard deviation (SD) on 450K methylation analysis, all the GCTs were clustered into two groups. The heatmap indicated 2 well-demarcated clusters, one with abundant demethylated probes, and the other with medium to highly methylated probes. The two clusters were related to histology; “Group A” was dominated by germinoma and seminoma and “Group B”, by mixed GCTs and NGGCT/NSGCT.