Due to the variable presentation of mosaic chromosomal abnormalities, cases such as this are needed to define the phenotypic spectrum. It also highlights the importance of chromosome analysis to identify structural abnormalities that result in aneuploidy.
Keywords: long‐term survival; mosaic trisomy 9; pseudo‐isodicentric chromosome 9.
© 2021 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.