Pediatric Ovarian Tumors Research Articles

Assessment of Molecular Markers in Pediatric Ovarian Tumors: Romanian Single-Center Experience.

Pediatric ovarian tumors exhibit unique diagnostic and therapeutic challenges. This study evaluates the expression of SALL4 and OCT3/4 biomarkers in pediatric ovarian tumors and their associations with tumor subtype, stage, and clinical outcome. A retrospective analysis was conducted on 64 patients under 18 years old, examining demographic data, tumor characteristics, immunohistochemical staining, and clinical outcomes. Our results show that SALL4 was significantly expressed in adenocarcinoma, dysgerminoma (DSG), mixed germ cell tumors (GCTs), and immature teratoma, while OCT3/4 was highly expressed in DSG and mixed GCTs. Both markers are associated with a higher tumor grade and stage, indicating a more aggressive disease. The SALL4 positivity expression was correlated with high alpha fetoprotein (AFP) and lactate dehydrogenase (LDH) levels, while OCT3/4 positivity significantly predicted the risk of subsequent metastasis. The mean progression-free survival (PFS) was notably shorter in patients with positive markers. These findings underscore the diagnostic and prognostic value of SALL4 and OCT3/4 in pediatric ovarian tumors, aligning with previous research and supporting their use in clinical practice for better disease management and patient outcomes.

A Rare Case of Virilizing Ovarian Fibrothecoma in A Teenage Girl

Ovarian fibrothecomas comprise tumors in the spectrum of ovarian sex cord / stromal tumors where there are components of both an ovarian fibroma and an ovarian thecoma. They account for 3-4% of all ovarian tumors. Most occur in adult women, with 65% in postmenopausal women. However, it represents only 2% of pediatric ovarian tumors. They are the most common benign solid ovarian tumor. The tumors are usually hormonally inactive but can be estrogenic or sometimes androgenic. Here we are reporting a rare case of a 15-year-old girl presenting with primary amenorrhea, severe hirsutism and finally diagnosed with ovarian fibrothecoma. After surgical removal of the tumor, a dramatic response was observed as the patient developed menarche. She was relieved of her hirsutism by laser therapy later, but her deep voice remained the same. CBMJ 2024 January: vol. 13 no. 01 P: 95-97

Characteristics and Outcomes of Pediatric Ovarian Germ Cell Tumors: A Report of 162 Cases

Characteristics and Outcomes of Pediatric Ovarian Germ Cell Tumors: A Report of 162 Cases

Diagnostic Performance of Magnetic Resonance Imaging for Pediatric Ovarian Neoplasms: A Multi-Institutional Review

Study ObjectiveTo assess diagnostic performance of MRI to predict ovarian malignancy alone and compared to other diagnostic studies. MethodsRetrospective analysis of patients aged 2 to 21 years who underwent ovarian mass resection between 2009-2021 at eleven pediatric hospitals. Sociodemographic information, clinical and imaging findings, tumor markers, and operative and pathology details were collected. Diagnostic performance for detecting malignancy was assessed by calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for MRI with other diagnostic modalities. Results1,053 patients underwent resection of an ovarian mass with a median age of 14.6 years; 10% (110/1053) had malignant disease on pathology and 13% (136/1053) underwent preoperative MRI. MRI sensitivity, specificity, PPV, and NPV were 60%, 94%, 60%, 94%. Ultrasound sensitivity, specificity, PPV, and NPV were 31%, 99%, 73%, 95%. Tumor marker sensitivity, specificity, PPV, and NPV were 90%, 46%, 22%, 96%. MRI and ultrasound concordance was 88% with sensitivity, specificity, PPV, and NPV of 33%, 99%, 75%, 94%. MRI sensitivity in ultrasound-discordant cases was 100%. MRI and tumor marker concordance was 88% with sensitivity, specificity, PPV, and NPV of 100%, 86%, 64%, 100%. MRI specificity in tumor marker-discordant cases was 100%. ConclusionDiagnostic modalities used to assess ovarian neoplasms in pediatric patients typically agree. In cases of disagreement, MRI is more sensitive for malignancy than ultrasound and more specific than tumor markers. Selective use of MRI with preoperative ultrasound and tumor markers may be beneficial when the risk of malignancy is uncertain. Concise AbstractThis retrospective review of 1053 patients age 2-21 years who underwent ovarian mass resection between 2009-2021 at 11 pediatric hospitals found that ultrasound, tumor markers, and MRI tend to agree on benign vs malignant but in cases of disagreement, MRI is more sensitive for malignancy than US.

11. Diagnostic Accuracy of Magnetic Resonance Imaging for Pediatric Ovarian Neoplasms

11. Diagnostic Accuracy of Magnetic Resonance Imaging for Pediatric Ovarian Neoplasms

Laparoscopy for Ovary-Sparing Tumorectomy in Children with Ovarian Tumors: A Clinical Retrospective Analysis.

Objective: The aim of this study is to analyze the characteristics of pediatric ovarian tumors (OTs) and evaluate treatment strategies for ovary-sparing tumorectomy (OST). Materials and Methods: Medical records of children from October 2011 to December 2021 were reviewed. Data regarding clinical characteristics, pathological type, and management of OST were analyzed. Results: In total, 61 patients with OTs were screened. The median age was 14.8 ± 3.0 years. The median length and volume of borderline and malignant OTs were larger than those of benign OTs (P < .001 and P = .05, respectively). There was a significant difference in the median OT volume between torsion and nontorsion OTs (P = .04). The overall OST rate was 91.8% (67/73). A total of 53.4% (39/73) lesions were treated with laparoscopic OST. The OT volume was smaller in patients who underwent laparoscopy than in those who underwent laparotomy (P = .04). The probability of intraoperative tumor rupture or spillage was higher during laparoscopy than during laparotomy (P = .02). No significant differences were observed in OT recurrence. Seven patients had borderline and malignant tumors, 3 of whom had stage IA tumors and underwent OST. None of the patients experienced relapse. Conclusions: OT size is a useful reference factor for differential diagnosis and choosing laparoscopic surgery. Intraoperative tumor rupture and spillage of benign tumors during laparoscopy and laparotomy did not seem to be associated with recurrence, and laparoscopic OST was considered safe. Further prospective studies are required to confirm these conclusions.

Imaging of pediatric ovarian tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Ovarian tumors in children are uncommon. Like those arising in the adult population, they may be broadly divided into germ cell, sex cord, and surface epithelium subtypes; however, germ cell tumors comprise the majority of lesions in children, whereas tumors of surface epithelial origin predominate in adults. Diagnostic workup, including the use of imaging, requires an approach that often differs from that required in an adult. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary ovarian malignancy at diagnosis and during follow-up.

Long-term surgical outcomes in pediatric ovarian neoplasms: 20-year single-center experience.

The management of pediatric ovarian neoplasms (ON) is based on finding a balance between adequate surgical treatment and future reproductive capacity. We aimed to evaluate long-term results of patients who underwent surgery for ON. A retrospective cohort study design was used. Medical records of patients with ON were reviewed. They were invited to participate in a telephone-based survey assessing complaints, menstrual status, and post-surgical recurrence. Eighty-five patients were operated for ON between 1995 and 2015. Median age at surgery was 14.7years. 62.4% of patients had ovary-sparing surgery (OSS). Median tumor size in oophorectomy group was significantly larger than OSS group (p = 0.029). Median length of follow-up was 5.1years. Recurrent/metachronous disease was not significantly different between OSS and oophorectomy groups (p = 1.000). In OSS group, irregular menses (p = 0.004) and painful menses (p = 0.002) were significantly higher than oophorectomy group. The main goal of treatment in pediatric ON is to find the right balance between adequate and appropriate tumor resection and maximal effort for fertility preservation. Our results showed no difference between oophorectomy and OSS in the terms of recurrence. Although irregular and painful menses were found to be significantly higher in the OSS group, longer follow-up and prospective studies are needed to clarify this issue.

Fever and Abdominal Pain in a 10-year-old with Autism.

Fever and Abdominal Pain in a 10-year-old with Autism.

The diagnostic value of magnetic resonance imaging in differentiating benign and malignant pediatric ovarian tumors

BackgroundThe diagnostic workup of ovarian tumors in children and adolescents is challenging because preserving fertility, in addition to oncological safety, is of particular importance in this population. Therefore, a thorough preoperative assessment of ovarian tumors is required.ObjectiveTo investigate the diagnostic value of MR imaging in differentiating benign from malignant ovarian tumors in children and adolescents.Materials and methodsWe conducted a retrospective study of all children and adolescents age <18 years who underwent MR imaging of ovarian tumors during 2014–2019 at a pediatric specialty center. Two radiologists reviewed all MR imaging. We used pathology reports to define the histological diagnosis.ResultsWe included 30 girls who underwent MR imaging for an ovarian tumor. Signs indicative for malignancy were tumors with a diameter ≥8 cm, with areas of contrast enhancement, irregular margins, extracapsular tumor growth, and ascites. All benign and malignant ovarian tumors were correctly identified by the radiologists.ConclusionThe diagnostic utility of MR imaging in classifying ovarian tumors in children and adolescents as benign or malignant is promising and might aid in defining the indication for ovarian-sparing versus non-ovarian-sparing surgery. We recommend evaluating these tumors with MR imaging prior to deciding on surgical treatment.

Abstract A02: Pediatric ovarian cancer in the United States: Incidence trends over four decades

Abstract Objectives: Ovarian cancer is rare in children, accounting for 1% of childhood cancers. However, it is the most common cancer of the female genital tract in adolescents. Due to the rarity of the disease and the histologic and prognostic differences between pediatric and adult cases, there is a paucity of data describing incidence trends of pediatric ovarian cancer in the United States. It is unknown whether pediatric ovarian cancer has increased in incidence over time. The aim of the current study was to examine incidence and trends in pediatric ovarian cancer in the last four decades in the United States. Methods: We queried the Surveillance, Epidemiology, and End Results 9 database from 1975-2016 for age-adjusted ovarian cancer incidence rates for pediatric cases, aged 0 to 19 years. We used Joinpoint regression analyses to examine incidence trends stratified by race (white, blacks, and others, which included Hispanics, American Indians/Alaskan Natives, and Asian Pacific Islanders), histology (carcinoma, germ cell tumor, others), and age groups (0-14, and 15-19 years). Results: There were 897 pediatric ovarian cancer cases in the study. Whites accounted for 71.3% of tumors, and 75.6% of tumors were germ cell. Overall, there was a 46% increase in the incidence of pediatric ovarian tumors in (12.59 per 100,000 in 1975 vs. 18.38 per 100,000 in 2016). Average annual percent change (AAPC) was 0.9 (p &amp;lt; 0.05), and APC from 1975 to 1977 was 5.1 (p = 0.5), from 1977 to 2006 APC was 0.5 (p &amp;lt; 0.05), and from 2006 to 2016, APC was 1.3 (p &amp;lt; 0.05). There was an upward trend in tumor incidence in all racial groups, and age-adjusted incidence rate was highest among whites (18.95 per 100,000). Among whites, APC changed significantly between 1981 and 2016 (APC = 0.8, p &amp;lt; 0.05); however, among blacks, APC increased between 1997 and 2016 (APC = 1.3, p &amp;lt; 0.05); and among other races, it increased between 1975 and 1997 (APC=1.1, p&amp;lt;0.05) and between 2000 and 2016 (APC = 1.9 p &amp;lt; 0.05). Conclusions: In the past four decades, there has been a steady increase in the age-adjusted incidence rate of pediatric ovarian tumors, and while overall incidence is highest among whites, there has been a sharp increase in incidence among blacks and other minority populations, especially in the last two decades. This surveillance information may be relevant to issues germane to survivors of pediatric cancers, such as oncofertility issues. Citation Format: Kara M. Christopher, Eric Adjei Boakye, Justin M. Barnes, Matthew C. Simpson, Brittany J. Kline, Katherine Mass, Theresa L. Schwartz, Shannon Grabosch, Nosayaba Osazuwa-Peters. Pediatric ovarian cancer in the United States: Incidence trends over four decades [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr A02.

Operative management of pediatric ovarian tumors and the challenge of fertility-preservation: Results from the UK CCLG Surgeons Cancer Group Nationwide Study

BackgroundOvarian tumors in the pediatric age group are rare. A significant number of children with ovarian mass lesions present “out of hours “as surgical emergencies, and surgical management does not always involve a surgical oncologist. This multicenter study reports how the mode of clinical presentation may influence (i) operation (conventional open vs minimally invasive surgery (MIS)) and (ii) examines if young females presenting as surgical emergency(s) are more likely to undergo total oophorectomy or ovarian sparing surgery. MethodsRetrospective multicenter study amongst UK pediatric surgical oncology centers. Females <16 years with diagnosis of ovarian tumor from 2006 to 2016 were included. Functional/neonatal ovarian cysts were excluded. ResultsThree hundred ten patients with ovarian tumors treated at 12 surgical oncology centers were identified. Mean age at surgery was 11 years [IQR 8–14]. Most common diagnosis were mature teratoma (57%, 177 cases), immature teratoma (10.9%, 34 cases) and cystadenoma (12%, 36 cases). Seventy percent (217) of cases were performed as open procedures. Thirty percent (94) of children underwent MIS.Tumors were significantly smaller in children who underwent MIS. Median tumor size in the laparoscopic group was 6 cm compared to 11 cm in the open group (p < 0.00001). Children who underwent MIS were significantly more likely to have ovary sparing surgery. ConclusionThis UK nationwide study demonstrates that ovary-sparing surgery and minimally invasive surgery are still infrequently deployed by pediatric surgeons in the UK. Patients with smaller tumors were more likely to undergo MIS, and more frequently underwent ovary-sparing surgery. In view of the implications on fertility and hormonal health caused by unilateral oophorectomy, it is time to review this current practise and agree consensus guidelines to reduce rates of unnecessary oophorectomy. Level of evidence statementThis is a level II evidence study. It is a retrospective multicentre collaborative study, which summarizes data from a national cohort of children.

Results of Ovarian Sparing Surgery in Pediatric Patients: Is There a Place for Laparoscopy?

Background: Laparoscopy is widely accepted for the surgical treatment of benign ovarian lesions in adult women, with results similar to an open approach when spillage is avoided by different means such as endobag retrieval. This approach is controversial in children. Materials and Methods: Retrospective study (2009-2018) of all pediatric ovarian tumors with histological confirmation treated in a tertiary center. Data regarding preoperative selection criteria, surgical technique, and follow-up were registered. Laparoscopy was used only in tumors without malignant features and whose size allowed retrieving them through a small incision without morcellating. Emphasis was set in ovarian sparing surgery (OSS), comparing the results of open (OP) and laparoscopic (LPC) approach. Results: During the study period, 48 suspicious lesions in 45 patients were operated. Thirty cases (32 tumors) showed benign features (10 cystadenomas, 14 mature teratomas, 6 nontumor lesions); treatment consisted in oophorectomy in 13 (OP 6, LPC 7) and OSS in 17 (OP 5, LPC 12). There was one conversion in the LPC group. Mean follow-up was 3.44 years (range 0.03-8.84), based on annual ultrasound (US) and tumor markers during at least 5 years, recommending a lifetime follow-up by a gynecologist. There was only one relapse in a laparoscopically enucleated cystadenoma, and 2 patients developed contralateral metacronous teratomas. No procedure-related complications happened. Conclusions: Our series, although small and with a limited follow-up, suggest that laparoscopy could be an option of treatment in a subset of highly selected patients, although laparotomy remains the gold standard approach if malignancy is suspected.

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.

Understanding the Value of Tumor Markers in Pediatric Ovarian Neoplasms

PurposeThe purpose of this study was to determine the diagnostic accuracy of tumor markers for malignancy in girls with ovarian neoplasms. MethodsA retrospective review of girls 2–21 years who presented for surgical management of an ovarian neoplasm across 10 children's hospitals between 2010 and 2016 was performed. Patients who had at least one concerning feature on imaging and had tumor marker testing were included in the study. Sensitivity, specificity, and negative and positive predictive values (PPV) of tumor markers were calculated. ResultsOur cohort included 401 patients; 22.4% had a malignancy. Testing for tumor markers was inconsistent. AFP had high specificity (98%) and low sensitivity (42%) with a PPV of 86%. The sensitivity, specificity, and PPV of beta-hCG was 44%, 76%, and 32%, respectively. LDH had high sensitivity (95%) and Inhibin A and Inhibin B had high specificity (97% and 92%, respectively). ConclusionsTumor marker testing is helpful in preoperative risk stratification of ovarian neoplasms for malignancy. Given the variety of potential tumor types, no single marker provides enough reliability, and therefore a panel of tumor marker testing is recommended if there is concern for malignancy. Prospective studies may help further elucidate the predictive value of tumor markers in a pediatric ovarian neoplasm population. Type of StudyRetrospective Cohort Review. Level of EvidenceLevel III.

Ovarian neoplasms of childhood.

Ovarian neoplasms are rare in children. Although usually asymptomatic, they sometimes present with abdominal pain, abdominal distension or palpable mass. The distribution of neoplasms in the pediatric population is different from in adults; benign mature cystic teratoma is the most common ovarian tumor in children. Radiologists should be familiar with the variable sonographic, CT and MRI findings of ovarian neoplasms. Although the less frequently encountered ovarian malignancies cannot be reliably distinguished by imaging alone, it does play an important role in workup. This review discusses the imaging and relevant clinical manifestations of the more commonly encountered pediatric ovarian neoplasms.

Treatment strategy for pediatric giant mucinous cystadenoma: A case report.

Because of their rarity, the treatment strategy for pediatric ovarian epithelial tumors is controversial, especially for a giant cystadenoma. We report the largest mucinous cystadenoma (MCA) case in the pediatric literature thus far. A 12-year-old girl had abdominal distention and visited our hospital. She had a multilocular cyst with some protuberance on the inside and high values of CA 19-9 and CA-125. We diagnosed her with a left MCA and performed a left oophorectomy. The tumor was the stage IA borderline malignant MCA and weighed 11.8 kg. Five years have passed, the patient has not experienced recurrence or metastasis. The resection of giant tumors can affect respiration and circulation. However, pre- or intra-operative drainage may lead to dissemination and adhesion. When we treat pediatric giant ovarian epithelial tumors, we must understand the findings that suggest the possibility of malignancy to decide appropriately as to whether drainage should be performed.

Genetic Causes of Rare Pediatric Ovarian Tumors.

Ovarian tumors in childhood and adolescence are distinguished from those that arise in adulthood by their histological subtype. These tumors may arise as the first manifestation of a cancer predisposition syndrome. Correct diagnosis of the syndrome may offer the possibility of surveillance for other members of the patients family. To summarize current knowledge about paediatric ovarian tumors that may be associated with genetically defined cancer syndromes. Juvenile granulosa cell tumors occur in those with Ollier disease and Maffucci syndrome; they are caused by postzygotic IDH1 and IDH2 gene mutations. Sertoli-Leydig cell tumors usually arise in association with DICER1 syndrome, which is caused by germline DICER1 gene mutations. Sex cord tumors with annular tubules and Sertoli cell tumors may arise in patients with Peutz-Jeghers syndrome; this syndrome is caused by germline STK11 gene mutations. The majority of germ cell tumors develop in the context of gonadal dysgenesis. In XY gonadal dysgenesis, the presence of a Y chromosome material renders the patient at increased risk for developing gonadal malignancy. Characteristically, these patients develop gonadoblastoma, which has the potential to evolve into dysgerminoma and exhibit malignant behavior. Sex-chromosome aneuploidy syndromes or mutations in genes involved in gonadal development and differentiation may cause gonadal dysgenesis. Small cell carcinoma of the ovary of a hypercalcaemic type is usually caused by loss-of-function mutations in the SMARCA4 gene. Ovarian tumors are uncommon during childhood and adolescence. It is always necessary to consider gonadal dysgenesis or any of the inherited cancer syndromes. These patients require interdisciplinary care, careful noting of personal and family history, precise clinical examination, laboratory testing, and differential diagnosis by a clinician with a good knowledge of genetic syndromes. Expert pathological review may be required for correct diagnoses. This is necessary for appropriate management and to establish an association with hereditary cancer syndromes. The work was supported by the Ministry of Health of the Czech Republic - Conceptual Development of Research Organization, Faculty Hospital of Ostrava /2015. We thank to Lenka Foretová, M.D., Ph.D., (MMCI, Brno) and Radoslava Tomanová, M.D., (Institute of Pathology, University Hospital Ostrava) for rewarding advice, Mrs. Jana N&#283;mcová (Department of Medical Genetics, University Hospital Ostrava), Bc. Ludmila Stuchlá and Mrs. Lenka Ziv&#269;áková (Medical Library, University Hospital Ostrava) for help during manuscript preparation. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 10. 3. 2019 Accepted: 16. 4. 2019.

Factors Associated With Management of Pediatric Ovarian Neoplasms

Available evidence supports ovary-sparing surgery for benign ovarian neoplasms; however, preoperative risk stratification of pediatric ovarian masses can be difficult. Our objective of this study was to characterize the surgical management of pediatric ovarian neoplasms across 10 children's hospitals and to identify factors that could potentially aid in the preoperative risk stratification of these lesions. A retrospective review of girls and women aged 2 to 21 years who underwent surgery for an ovarian neoplasm between 2010 and 2016 at 10 children's hospitals was performed. Multivariable logistic regression was used to examine the relationships between the preoperative cohort characteristics, procedure performed, and risk of malignancy. Among 819 girls and women undergoing surgery for an ovarian neoplasm, malignant lesions were identified in 11%. The overall oophorectomy rate for benign disease was 33% (range: 15%-49%) across institutions. Oophorectomy for benign lesions was independently associated with provider specialty (P = .002: adult gynecologist, 45%; pediatric surgeon, 32%; pediatric gynecologist, 18%), premenarchal status (P = .02), preoperative suspicion for malignancy (P < .0001), larger lesion size (P < .0001), and presence of solid components (P < .0001). Preoperative findings independently associated with malignancy included increasing size (P < .0001), solid components (P = .003), and age (P < .0001). The rate of oophorectomy for benign ovarian disease remains high within the pediatric population. Identification of factors associated with the choice of procedure and the risk of malignancy may allow for improved preoperative risk stratification and fewer unnecessary oophorectomies. These results have been used to develop and validate a multidisciplinary preoperative risk stratification algorithm that is currently being studied prospectively across 10 institutions.

Pediatric ovarian immature teratoma: Histological grading and clinical characteristics

BackgroundOvarian immature teratomas (ITs) are relatively rare among all pediatric ovarian tumors. The histological grading for ovarian ITs, which ranges from 1 to 3, is based on the proportion of immature neuroepithelial component. Higher-grade ITs in adults are treated as malignant neoplasms and require adjuvant chemotherapy. However, there is no consensus on the therapeutic management of pediatric ovarian ITs. The aim of our study was to analyze the histological grades and clinical characteristics of ovarian ITs in pediatric patients. MethodsThis retrospective chart review consisted of seven patients, including one, three, and three patients with histological grade 1, 2, and 3 pediatric ovarian ITs, respectively, who were treated at our institute between 2000 and 2016. Collected data comprised age, alpha-fetoprotein (AFP) level, clinical stage, tumor size, treatment, and prognosis. ResultsThe median age and AFP levels of patients with grade 1, 2, and 3 ovarian ITs were 8, 7, and 10 years and 37, 112, and 221 ng/ml, respectively. All cases were Children Oncology Group (COG) stage I and International Federation of Gynecology and Obstetrics (FIGO) stage IA. All patients had unilateral tumors in the right ovary. The median tumor sizes of the grade 1, 2, and 3 IT patients were 104, 160, and 100 cm2, respectively. All patients underwent primary open surgery alone. Two patients, including one patient each with grade 2 and 3 ITs, underwent tumor enucleation as ovary-sparing surgery, whereas the remaining five patients underwent unilateral salpingo-oophorectomy. The median follow-up was seven years, and all cases achieved event-free survival. ConclusionsClinical characteristics of patients with grade 3 ovarian ITs were relatively older and had higher AFP levels than those with lower-grade ITs. According to our patient’s clinical course and prognosis, COG stage I pediatric ITs should be treated by surgery alone and that postoperative chemotherapy is unnecessary even for those with grade 3 ITs as well as patients with rather low AFP levels. Level of evidenceIV