CYTOGENETIC ABNORMALITIES AND CLONAL EVOLUTION IN AN ADULT HEPATOBLASTOMA

Hepatoblastomas usually occur in children < 3 years of age, and only o ccasional adult cases have been described. To date, 20 cytogenetically abnormal childhood hepatoblastomas have been reported. Karyotypic inv estigations have shown that most hepatoblastomas are diploid or hyperd iploid, often displaying trisomies for chromosomes 2 and 20. We have c ytogenetically investigated an adult hepatoblastoma for which no previ ous karyotypic data exist. A hypertriploid stemline with multiple nume rical and structural chromosomal aberrations, including +2 and +20, wa s found. In addition, the tumor displayed extensive clonal evolution w ith 11 subclones. Although the tumor thus displayed some chromosomal a bnormalities commonly observed in childhood tumors, providing further support for the importance of these abnormalities in the development o f hepatoblastoma, the level of genomic complexity seen in the present case has never been described in childhood hepatoblastomas and may sug gest a different etiology or pathogenesis.