SIGNIFICANCE OF CHROMOSOME 1P LOSS OF HETEROZYGOSITY IN NEUROBLASTOMA

We analyzed 156 primary neuroblastoma tumor samples for loss of hetero zygosity at the distal short arm of chromosome 1 (1p LOH). We also com pared Ip LOH with known clinical and genetic prognostic variables as w ell as patient outcome, Ip LOH was detected in 30 of 156 tumors (19%) and was strongly associated with adverse clinical and biological featu res. 1p LOH was also strongly predictive of a poor outcome in univaria te analyses (estimated 4-year survival, 32 +/- 10% SE versus 76 +/- 5% SE; P < 0.001). However, the prognostic value of Ip LOH was equivocal when stratified for amplification of the MYCN oncogene (P = 0.16). We conclude that 1p LOH is an important component of a pattern of geneti c abnormalities in neuroblastoma associated with an aggressive clinica l course.