2ND MALIGNANT NEOPLASMS IN CHILDREN WITH RETINOBLASTOMA - THE ST-JUDE-CHILDRENS-RESEARCH-HOSPITAL EXPERIENCE

A retrospective review of 172 children with primary diagnosis of retin oblastoma(RB) was completed at St. Jude Children's Research Hospital t o evaluate the incidence of second malignant neoplasm (SMN) developmen t. Sixty-five patients presented with bilateral RE and IO7 with unilat eral RE. During follow-up, which ranged from 6 to 340 months (median = 170 months), 6 children (3.5%) developed SMN. All patients who develo ped SMN presented with bilateral disease (n=5) or asynchronous bilater al disease (n=I); two patients had a family history of RE. All had rec eived irradiation. Four patients developed osteogenic sarcoma within t his irradiated volume, one developed a basal cell carcinoma in the tem poral region (within the irradiation held), and one was diagnosed with a lower extremity Ewing's sarcoma. Time to development of SMN ranged from 125 to I94 months postirradiation. Initial irradiation total dose ranged between 32 and 45.76 Gy Three patients were treated with anter ior held irradiation and three received lens-sparing techniques (anter ior/lateral n=2, lateral n=I). At last followup, 4/6 patients had died of SMN. The crude incidence is 3.5% with an estimation of risk using the density method of 24% at 20 years for SMN development. The specifi cs of the treatment associated with these second malignancies and the possible reasons for the reported incidence of SMN will be discussed.