Loss of heterozygosity at 19q13.3 is associated with locally aggressive neuroblastoma

A genome-wide allelic analysis of neuroblastoma (NB) revealed a previously undescribed increased incidence of loss of heterozygosity (LOH) on chromoso me arm 19q13 primarily affecting stages 3 and 4N disease. Further allelic a nalysis of chromosome 19q13 in a cohort of 116 NE patients using 17 polymor phic microsatellite markers identified the shortest common region of loss b etween D19S606 and D19S112 at 19q13.3. In some cases, clonal LOH at 19q13 w as acquired during the course of disease, and deleted clones remained after cytotoxic therapy. In multivariant analysis, 19q13 LOH was associated with overall survival in local-regional International Neuroblastoma Staging Sys tem stages 1, 2, and 3 patients and was specifically present in tumors at t he site of recurrence.