A comprehensive population-based study of malignant ovarian tumors, including histologic and immunohistochemical review, in children and adolescents 0-19 years old in Sweden between 1970 and 2014.

OBJECTIVES: Ovarian tumors in the pediatric population are rare. The incidence and frequency of subtypes differ between children and adults. Although not all tumors are aggressive, they may still lead to morbidity. The goal of this study was a comprehensive review of malignant ovarian tumors in children and adolescents diagnosed and registered in Sweden. METHODS: Individuals were identified through a search in the National Cancer Register, limited for ages 0-19, years 1970-2014. Stored tumor diagnostic material from regional biobanks was retrieved and reviewed. RESULTS: The study includes 345 individuals with ovarian tumors and 70.7% of them were between 15 and 19 years at time of diagnosis. No differences in incidence over time or geographic location were identified. The average follow-up time was 21.2 years and 5-year survival was 88.4%. Survival was similar in the different time periods, except for 1970-1979. Review was possible for 260 cases, resulting in 85 epithelial tumors, 121 GCTs, 47 SCSTs and 7 others. For age 0-4 years SCSTs dominated (85.7%), for 5-9- and 10-14-years GCTs dominated (70,8% and 75.0% respectively), and for age 15-19 years epithelial tumors dominated (43.8%). There was a strong agreement between review diagnosis and original diagnosis (Cohen's κ 0.944). Differentiating between entities within the sex cord-stromal group posed the biggest diagnostic challenge. CONCLUSIONS: Ovarian tumors in children and adolescents are rare and distinct from their adult counterparts regarding incidence and frequency. There was a strong concurrence between original and review diagnoses. The greatest diagnostic difficulty was subtyping of epithelial tumors and differentiating between tumors within the SCST group.

Imaging in pediatric ovarian tumors.

The spectrum of ovarian tumors in the pediatric population differs significantly from that in adults. Germ cell tumors are the predominant class of ovarian tumors in children, whereas epithelial tumors are the most common in adults. Ultrasonography is the modality of choice for the initial evaluation of pediatric ovarian tumors. Determining the diagnosis based on imaging may prove difficult, and combining the imaging findings with the clinical scenario is very helpful in reaching a differential diagnosis during clinical practice. We will discuss the spectrum of ovarian neoplasms in the pediatric population and describe their clinical, pathologic, and imaging characteristics. A few unique entities related to ovarian tumors, such as growing teratoma syndrome, anti-N-methyl-D-aspartate receptor encephalitis, and hereditary ovarian tumor syndromes, are also discussed. In addition, we will review several entities that may mimic ovarian neoplasms as well as their distinct imaging features.

Ovarian-Sparing Surgery in Pediatric Benign Ovarian Tumors.

STUDY OBJECTIVE: To evaluate outcomes of children after ovarian-sparing surgery (OSS) for non-neoplastic and benign neoplastic ovarian lesions. DESIGN: Retrospective cohort study from January 2003 to January 2012. SETTING: Single, high-volume, tertiary care hospital. PARTICIPANTS: Children 18 years of age and younger. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Postoperative complications and tumor recurrence after OSS. RESULTS: One hundred nine patients underwent OSS with a median age of 13.3 years (interquartile range [IQR], 11.4-15.1 years). Eighty-two patients were treated laparoscopically with 4 conversions to an open procedure. Postoperative complications included surgical site infections in 7 patients (6%). Pathology most commonly revealed functional ovarian cysts (n = 57) and mature teratomas (n = 37). Ninety-four patients (86%) were followed for a median of 10.4 months (IQR, 0.72-30.8 months). Fifty-five patients (60%) had subsequent imaging surveillance a median of 7.6 months postoperatively (IQR, 3.9-13 months). Ten patients (10%) developed a second ipsilateral lesion within a median time of 11 months (IQR, 7.7-24 months), of whom 5 girls had repeated surgery for mass enlargement or persistent abdominal pain at a median time of 10.5 months (IQR, 8.0-12.65 months). Fifty-eight patients (63%) began or resumed menses at their most recent follow-up. Three girls became pregnant after OSS at a median follow-up of 5 years (range, 2.4-6.7 years). CONCLUSION: Benign ovarian lesions in children can be treated successfully with OSS with low recurrence and repeat surgery rates.

Epithelial Tumors of the Ovary in Children and Teenagers: A Prospective Study from the Italian TREP Project.

STUDY OBJECTIVE: To report the clinical findings and treatment results of a series of patients with epithelial tumors of the ovary, registered and treated prospectively in a multi-institutional Italian network (TREP project) on rare tumors in children and adolescent between 2000 and 2014. DESIGN, SETTING, AND PARTICIPANTS: Data on 16 patients, aged 22 to 206 months, from 7 centers were reviewed. All patients were grouped on the basis of the results of the first surgical approach, according to the Children Oncology Group staging system. RESULTS: The most frequent symptom was abdominal pain; 3 patients were hospitalized for acute pain after ovarian torsion. Initial surgical treatment was complete in 15 of 16, and a biopsy was performed in 1 of 16. The histology examination revealed 8 benign tumors (7 mucinous cystadenomas and 1 serous cystadenoma) and 8 borderline tumors (2 serous and 6 mucinous). Fifteen of 16 patients maintained the complete remission after surgical treatment alone; 1 affected by Proteus syndrome died consequent to the progression of a synchronous Wilms tumor, after a delayed incomplete surgery. CONCLUSION: Our analysis documented the rarity of these tumors in children and adolescents. No malignant histologies were found. Surgery alone was effective to cure the majority of patients. Considering the rarity of malignant entities, ovary-sparing surgery may be planned when an epithelial tumor is suspected on the basis of the preoperative work-up and intraoperative findings.