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[Topotecan for pediatric patients with resistant and recurrent solid tumors].

BACKGROUND
Topotecan is a cytotoxic drug isolated from the Camptotheca acuminata tree (from China). It is able to block the enzyme DNA topoisomerase I and has recently been used in the treatment of pediatric cancer.


OBJECTIVES
To evaluate our preliminary experience with topotecan in the second line treatment of refractory solid tumors in the pediatric age group. PATIENTS AND MEHTODS: We performed a retrospective study of 10 patients with various recurrent solid tumors resistant to first line treatment who were treated with topotecan alone or in association with other chemotherapeutic agents.


RESULTS
Ten patients with recurrent solid tumors or tumors that were refractory to conventional treatment (two neuroblastomas, three rhabdomyosarcoma, two PNET/Ewing's sarcoma, one anaplastic astrocytoma, one soft tissue sarcoma and one synovial sarcoma) were included. Five patients showed favorable responses (two had complete responses, two had partial responses and one had stable disease). Five patients showed no response. All patients showed grade II-IV hematological toxicity.


CONCLUSIONS
In our experience, topotecan is beneficial in some refractory or recurrent solid tumors, especially neuroblastomas and soft tissue sarcomas. Myelosuppression was tolerable with the use of granulocyte colony-stimulating factors. Patients with a complete response to topotecan could benefit from high-dose chemotherapy and autologous stem cell rescue therapy.