Ewing sarcoma-family tumors that arise after treatment of primary childhood cancer

Abstract

Background: Unlike osteosarcoma, the Ewing sarcoma family of tumors (ESFT) has rarely been reported as secondary malignant neoplasms after treatment of childhood cancer. ESFT arising as a second cancer was reviewed and characterized at our childhood cancer center.

Methods: A retrospective review was undertaken of 11,183 patients age <21 years who were treated for a primary cancer between March 1962 and December 2003 at St. Jude Children's Research Hospital. All cases of ESFT were confirmed to have a rearranged EWS gene.

Results: Six cases of ESFT (1.3% of 479 second cancers) were identified in patients previously treated for lymphoma (n = 3), leukemia (n = 1), retinoblastoma (n = 1), or Wilms tumor (n = 1). None of these patients had a family history suggestive of a familial cancer syndrome. The median time between diagnosis of primary cancer and diagnosis of ESFT was 5.9 years (range, 3.1-18.3 years). ESFT occurred in typical anatomic locations: rib (n = 2), chest wall soft tissues (n = 2), pelvis (n = 1), and extremity (n = 1). One tumor arose at the margin of a previous radiotherapy field and 1 arose distant from previous radiotherapy fields; all other patients had not received radiotherapy. Three patients are alive at the time of this report, including 2 whose ESFT was diagnosed more than 8 years ago.

Conclusions: ESFT occurs rarely after treatment of a primary cancer during childhood, and most cases do not appear to be related to radiation therapy. Long-term survival can be achieved in some patients, and therefore secondary ESFT should be treated with curative intent.