Malignant lesions of the ovary in childhood.

Approximately half of all lesions of the ovary in childhood are neoplastic, yet only a small fraction of neoplastic lesions contain malignant elements. Overall, malignancies of the ovary account for 10% of all ovarian masses and 1% of childhood cancers. Primary ovarian malignancies fall into three broad categories based on the cell type of origin. Germ cell tumors predominate and may be further subdivided based on the differentiation of the malignant cells. Epithelial cell tumors, which are most common in adults, and sex-cord stromal tumors each make up 15% of the total in children. Rare malignant lesions and metastatic disease account for the small remaining group of tumors. Regardless of tumor type, the majority of patients present with localized disease, but proper surgical staging is important to determine the need for adjuvant therapy. The development of platinum-based chemotherapeutic regimens has resulted in significant improvements in long-term survival, even for children who present with advanced stage disease.