Treatment of neuroblastoma in congenital central hypoventilation syndrome with a PHOX2B polyalanine repeat expansion mutation: New twist on a neurocristopathy syndrome.

Neuroblastoma in patients with congenital central hypoventilation syndrome (CCHS) as part of a neurocristopathy syndrome is a rare finding and has only been associated with paired-like homeobox 2b (PHOX2B) non-polyalanine-repeat-expansion mutations. To the best of our knowledge, we report the first case of a child with CCHS and Hirschsprung disease who had a PHOX2B polyalanine-repeat-expansion mutation (PARM) (genotype 20/33) and developed high-risk neuroblastoma. We further describe his treatment including chemotherapy and therapeutic I(131) -metaiodobenzylguanidine. This case highlights the need to consider neuroblastoma in patients with CCHS and the longest PHOX2B PARMs and to individualize treatment based on co-morbidities.