Magnetic resonance imaging of pediatric adnexal masses and mimics

Ovarian cancer in children and adolescents: A unique clinical challenge

Ovarian cancer in children and adolescents is rare, presenting unique diagnostic and management challenges distinct from adult cases. This paper provides a comprehensive overview of this disease, focusing on the importance of a multidisciplinary approach to care. We discuss the common presentation of ovarian malignant masses in young patients, highlighting the role of imaging and tumor markers in diagnosis. The paper delves into the surgical management of these tumors, emphasizing the importance of fertility-sparing techniques whenever possible. We explore the role of adjuvant chemotherapy, considering histological subtypes and disease stage. Furthermore, we address the good prognosis associated with early diagnosis and treatment, with survival rates exceeding 90 % in many cases. Finally, the need for long-term follow-up to monitor for potential recurrence is underscored and the long-term treatment-related effects are addressed. This review aims to guide clinicians in providing optimal care for this unique patient population, emphasizing the importance of balancing oncological control with the preservation of future fertility and quality of life.

The Evaluation, Diagnosis, and Management of Ovarian Cysts, Masses, and Their Complications in Fetuses, Infants, Children, and Adolescents

The majority of abdominal masses in female children derive from the ovaries. Ovarian masses in pediatric populations can vary from simple functional cysts to malignant neoplasms. Their incidence, clinical presentation, and histological distribution vary across age groups. In the assessment of ovarian masses in children, the primary aim is to determine the probability of malignancy, as the treatment approaches for benign and malignant lesions are significantly distinct. The primary imaging tool for evaluating ovarian cysts and masses is ultrasound, which can assess the size, location, and characteristics of masses. Magnetic resonance imaging (MRI) or computed tomography (CT) may be used for further evaluation if ultrasound findings are inconclusive or if malignancy is suspected, especially in older adolescents. Serum markers may be considered in older adolescents to help assess the risk of malignancy, though it is less useful in younger populations due to normal developmental variations. Many functional ovarian cysts, especially those detected in fetuses or infants, often resolve spontaneously without intervention. Surgical intervention is indicated in cases of large cysts that cause symptoms, or if there are concerns for malignancy. Common procedures include primarily ovarian sparing laparoscopy or laparotomy. Complications like torsion, rupture, or hemorrhage may require urgent surgical intervention. Treatment should be performed in specialized centers to avoid unnecessary oophorectomies and ensure the best possible outcome for the patient. This comprehensive review aims to provide an overview of the evaluation, diagnosis, and treatment of ovarian masses in the pediatric population. Emphasis is placed on the particularities of the lesions and their management in relation to age subgroups.

Ovarian Masses in Children and Adolescents: A Review of the Literature with Emphasis on the Diagnostic Approach

Most abdominal masses in the pediatric population derive from the ovaries. Ovarian masses can occur in all ages, although their incidence, clinical presentation and histological distribution vary among different age groups. Children and adolescents may develop non-neoplastic ovarian lesions, such as functional cysts, endometrioma, torsion, abscess and lymphangioma as well as neoplasms, which are divided into germ cell, epithelial, sex-cord stromal and miscellaneous tumors. Germ cell tumors account for the majority of ovarian neoplasms in the pediatric population, while adults most frequently present with epithelial tumors. Mature teratoma is the most common ovarian neoplasm in children and adolescents, whereas dysgerminoma constitutes the most frequent ovarian malignancy. Clinical manifestations generally include abdominal pain, palpable mass, nausea/vomiting and endocrine alterations, such as menstrual abnormalities, precocious puberty and virilization. During the investigation of pediatric ovarian masses, the most important objective is to evaluate the likelihood of malignancy since the management of benign and malignant lesions is fundamentally different. The presence of solid components, large size and heterogenous appearance on transabdominal ultrasonography, magnetic resonance imaging and computed tomography indicate an increased risk of malignancy. Useful tumor markers that raise concern for ovarian cancer in children and adolescents include alpha-fetoprotein, lactate dehydrogenase, beta subunit of human chorionic gonadotropin, cancer antigen 125 and inhibin. However, their serum levels can neither confirm nor exclude malignancy. Management of pediatric ovarian masses needs to be curative and, when feasible, function-preserving and minimally invasive. Children and adolescents with an ovarian mass should be treated in specialized centers to avoid unnecessary oophorectomies and ensure the best possible outcome.

Added value of gadolinium-based contrast agents for magnetic resonance evaluation of adnexal torsion in girls

PURPOSE

Ultrasound is the first-line imaging modality to evaluate adnexa in girls with clinical suspicion of torsion. Patients with equivocal ultrasound findings can undergo MRI for better delineation of adnexal pathology. Here, we assess the utility of intravenous contrast in MRI evaluation of adnexal torsion in children.

METHODS

Two pediatric radiologists (R1, R2) retrospectively reviewed 198 pelvic MRI exams in 172 girls (median age 15 years). Each MRI was reviewed twice. The first review included pre-contrast images only. A second review, at least 1 month later, included both pre- and post-contrast images. Readers concluded if findings were suspicious for torsion or not. Readers' findings were compared to each other's and to surgical and MRI reports and clinical course.

RESULTS

198 MRI exams yielded 354 evaluable ovaries. Surgical and pathological reports were available for 47 patients. 11 patients had adnexal torsion. Both readers accurately diagnosed acutely torsed ovaries during pre- and post-contrast reviews (n = 4). However, readers disagreed on torsed paraovarian cysts (n = 4) and chronically/intermittently torsed ovaries (n = 3). In 21 non-torsed ovaries that had lesions, one or both readers concluded that there were pre-contrast features of torsion. In this set with ovarian lesions, contrast helped readers to correctly conclude no torsion (R1 = 8, R2 = 6) more commonly than to incorrectly conclude torsion (1 each), improving post-contrast specificity for each reader.

CONCLUSIONS

Post-contrast sequences did not provide additional benefit in evaluating acutely torsed ovaries but helped in excluding torsion in patients with adnexal lesions. Therefore, contrast administration should be individualized, potentially reserved only for those with abnormal ultrasound or pre-contrast images.

Diagnostic Performance of a Sonographic Volume and Solid Vascular Tissue Score (VSVTS) for Preoperative Risk Assessment of Pediatric and Adolescent Adnexal Masses

STUDY OBJECTIVE

To evaluate the diagnostic performance of a Volume and Solid Vascular Tissue Score (VSVTS) for preoperative risk assessment of pediatric and adolescent adnexal masses.

DESIGN

A retrospective cohort study comprised of all female individuals who presented with an adnexal mass that was managed surgically between April 2011 and March 2016.

SETTING

The Hospital for Sick Children (Toronto, Ontario, Canada).

PARTICIPANTS

Female individuals 1-18 years of age who presented to a large tertiary pediatric hospital with an adnexal mass that was managed surgically.

MAIN OUTCOME MEASURES

Main outcome measures included diagnostic performance of the VSVTS for malignancy via sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), negative likelihood ratio (LR-), and receiver operating characteristic area-under-the-curve (AUC) analysis.

RESULTS

A total of 179 masses in 169 subjects were included. The malignancy rate was 10.6%. The AUC for the VSTVS was 0.919. A VSTVS cut-off value of 4 achieved a sensitivity of 79% (95% CI 0.54-0.93), specificity of 88% (95% CI 0.82-0.93), PPV of 0.44 (95% CI 0.33-0.56), NPV of 0.97 (95% CI 0.94-0.99), LR+ of 6.77 (95% CI 4.18-10.97), and LR- of 0.24 (95% CI 0.10-0.57).

CONCLUSIONS

A sonographic scoring system based on the volume and presence of solid vascular tissue improves PPV for preoperative risk stratification of adnexal masses in the pediatric and adolescent population compared to existing ultrasound-only approaches. Further prospective research is needed to determine how best to incorporate components of such scoring systems into clinical management algorithms.

MR imaging in discriminating between benign and malignant paediatric ovarian masses: a systematic review

OBJECTIVES

The use of magnetic resonance (MR) imaging in differentiation between benign and malignant adnexal masses in children and adolescents might be of great value in the diagnostic workup of sonographically indeterminate masses, since preserving fertility is of particular importance in this population. This systematic review evaluates the diagnostic value of MR imaging in children with an ovarian mass.

METHODS

The review was made according to the PRISMA Statement. PubMed and EMBASE were systematically searched for studies on the use of MR imaging in differential diagnosis of ovarian masses in both adult women and children from 2008 to 2018.

RESULTS

Sixteen paediatric and 18 adult studies were included. In the included studies, MR imaging has shown good diagnostic performance in differentiating between benign and malignant ovarian masses. MR imaging techniques including diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging seem to further improve the diagnostic performance.

CONCLUSION

The addition of DWI with apparent diffusion coefficient (ADC) values measured in enhancing components of solid lesions and DCE imaging may further increase the good diagnostic performance of MR imaging in the pre-operative differentiation between benign and malignant ovarian masses by increasing specificity. Prospective age-specific studies are needed to confirm the high diagnostic performance of MR imaging in children and adolescents with a sonographically indeterminate ovarian mass.

KEY POINTS

• MR imaging, based on several morphological features, is of good diagnostic performance in differentiating between benign and malignant ovarian masses. Sensitivity and specificity varied between 84.8 to 100% and 20.0 to 98.4%, respectively. • MR imaging techniques like diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging seem to improve the diagnostic performance. • Specific studies in children and adolescents with ovarian masses are required to confirm the suggested increased diagnostic performance of DWI and DCE in this population.