The appearance of the low amount (<2) of the positive droplets has been seen after preamplification in several samples with confirmed H3 wild type status belonging to patients with the infant-type hemispheric glioma, ETV6-NTRK3-positive (sample #1), posterior fossa ependymoma, group A (sample #7), diffuse pediatric-type high-grade glioma, H3-wildtype, and IDH-wildtype (sample #8) and pilocytic astrocytoma, KIAA1549 (exon 15)—BRAF (exon 9)—positive (sample #14). This evidence concerns the gene NTRK3 and central nervous system cancer.