Coexistence of peripheral primitive neuroectodermal tumor and tetralogy of Fallot.

We describe a little girl with tetralogy of Fallot (TOF) who was found to have a huge peripheral primitive neuroectodermal tumor (pPNET) when she developed progressive difficulty in standing and crawling at the age of 11 months. The tumor was located in the left paraspinal region (T4-T12), with intraspinal extension causing severe compression. Nine days after surgical decompression with laminectomy, chemotherapy was initiated with alternative courses of vincristine, doxorubicin, cyclophosphamide, etoposide, and ifosfamide every 3 weeks. The muscle power in her legs recovered substantially after 2 courses of chemotherapy. Although peripheral blood for cytogenetic study revealed no chromosome abnormality, recent cytogenetic analysis has revealed a high frequency of reciprocal translocation t(11;22)(q24;q12) detected in pPNET and a strong association between TOF and chromosome 22q11 microdeletion (del 22q11). Both genetic defects involve chromosome 22q in the close region. This case report illustrates the necessity of investigating for cytogenetic change in chromosome 22 and close follow-up due to the possibility of subsequent development of malignancies in patients with TOF.