Emília Kaiserová, Viliam Žilinek, Ján Čáp, Oľga Mažáriová, Judita Puškáčová
Introduction: The second malignancies are serious late effect of primary malignancy treatment in childhood. They occur also as the second bone tumors, usually osteosarcomas. Most often they arise in the place of previous radiotherapy, but especially after retinoblastoma they develop also outside of irradiated field. Second malignancies are observed after primary bone tumors too: radiation-induced second solid tumors and chemotherapy-induced hematological malignancies. Goal: Evaluation of occurrence and treatment results of the second malignancies in patients with bone tumors. Focus is on early diagnosis of the second malignancies. Methods: Retrospective analysis of group of 40 patients with Ewing sarcoma and 52 with osteosarcoma, treated in years 1992 - 2005. Results: One case of the second Ewing sarcoma occurred after treatment of chorioid plexus carcinoma (the patient died) and two second osteosarcomas arose after retinoblastoma treatment. These patients are alive in the first and the second complete remission 2 and 8 years after diagnosis and treatment according to protocols for osteosarcoma (IOR 2 and COSS 96). Two cases of the second acute myeloid leukemia occurred after osteosarcoma treatment. Tolerance of leukemia treatment was bad and patient died 5 months after AML diagnosis. Conclusion: Unfavorable prognosis of the second malignant tumors has been improved with early diagnosis and with more intensive combined modality therapy, similar that applied for primary malignancies. Prognosis of the second leukemia has been worse than of the primary acute leukemia.