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Recurrence and Metachronous Disease in Children with Benign Ovarian Tumors: A Systematic Review of the Literature.

AIM
 The majority of ovarian tumors in children are benign, with good prognosis following complete resection. Little is published on the incidence of tumor recurrence and metachronous disease, and follow-up management of children with benign ovarian tumors (BOTs) remains a matter of debate. This systematic review aimed to evaluate the incidence and timing of recurrence and metachronous disease in children with BOTs in pediatric literature.


METHODS
 Comprehensive literature searches of the English literature (PubMed, OVID, EMBASE databases) from inception to present according to the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Outcomes for tumor recurrence and metachronous disease were synthesized.


RESULTS
 Nineteen studies comprising 1,069 patients with BOTs were included in the analysis. All studies were retrospective cohort studies of children less than 18 years old. A total of 56 events of recurrence or metachronous disease were reported in these patients. The overall risk of recurrence/metachronous event occurrence was 5.2%/2.9%. Seventy-five percent of events occurred within the first 4 years following resection.


CONCLUSION
 Although the studies identified are few and heterogeneous, they demonstrate a significant risk of tumor recurrence and metachronous disease for children following resection of a BOT.Especially following total unilateral oophorectomy, these children are at risk of losing the contralateral ovary in case of metachronous disease.Immediate discharge from follow-up, therefore, does not appear safe. The majority of events occurred within the first 4 years following resection. Follow-up for children following resection of a BOT should, therefore, be continued for a minimum of 4 years following surgery. Larger, long-term prospective studies are required to more accurately determine the true incidence and long-term outcomes for children and adolescents with these tumors.