Gonadal tumors in a contemporary cohort of patients with differences in sex development undergoing surgery - A multi-site study from the Pediatric Urologic Oncology Working Group of the societies for pediatric urology.

BACKGROUND: Disturbances in gonadal development lead to increased risk of gonadal malignancy in some but not all patients with differences in sex development (DSD). However, the natural history of these tumors is poorly described, and the literature remains sparse. OBJECTIVE: The objective of this study was to describe the incidence of germ cell neoplasia in situ (GCNIS) and germ cell tumor (GCT) in a contemporary cohort of patients with DSD undergoing surgery and to provide long-term oncologic outcomes for these patients. STUDY DESIGN: Patients with DSD who have undergone gonadectomy or gonadal biopsy were identified at four institutions. Clinical characteristics, pathology, and treatment details were obtained retrospectively. Patients were stratified into risk categories based on DSD diagnosis. Oncologic treatment and outcomes were recorded. Descriptive statistics are reported using parametric methods. RESULTS: 83 patients were identified. Distribution of diagnoses is summarized in the summary table. 14 (16.9%) patients underwent gonadal biopsy, and 71 (85.5%) patients underwent gonadectomy (50/71 gonadectomies were bilateral). 8/83 (9.6%) patients had GCNIS or GCT (7 GCNIS, 1 GCT). Median age at surgery was 2.95 years (y) (interquartile range [IQR] 0.6-12.2) and 14y (IQR 0.85-16.9) in patients without and with GCNIS/GCT, respectively. All 8 patients with GCNIS/GCT had high or intermediate risk DSD diagnoses (4 mixed gonadal dysgenesis, 3 Turner with Y, 1 partial gonadal dysgenesis). Of the patients with high-risk diagnoses, 8/54 (15%) had GCNIS/GCT. No patient received adjuvant therapy, no patient had a recurrence, and all patients were living with mean follow up 6.4y. DISCUSSION: The risk of gonadal malignancy is heterogeneous in the DSD population and can vary based on DSD diagnosis as well as maturation, testicularization, and location of the gonads. The most recent consensus recommendations on gonadal management emphasize risk stratification and consideration of gonadal surveillance based on gender of rearing, but supporting literature remains sparse. In this contemporary cohort of DSD patients who underwent gonadal surgery, most patients did not have evidence of adverse pathology, all patients with malignant or premalignant pathology had a high/intermediate risk DSD diagnosis, and all patients with GCNIS/GCT were treated with surgery alone without recurrence. CONCLUSIONS: The distribution of patients with premalignant and malignant gonadal pathology and DSD in this cohort aligns with prior literature, and oncologic outcomes were excellent. These data add valuable information to the current literature and highlight the necessity to develop appropriate screening regimens for retained gonads.

Validation of the modified Bosniak classification system to risk stratify pediatric cystic renal masses: An international, multi-site study from the pediatric urologic oncology working group of the societies for pediatric urology.

BACKGROUND: Pediatric cystic renal lesions are challenging to manage as little is known about their natural course. A modified Bosniak (mBosniak) classification system has been proposed for risk stratification in pediatric patients that takes ultrasound (US) and/or computed tomogram (CT) characteristics into account. However, literature validating this system remains limited. OBJECTIVE: To determine if the mBosniak classification system correlates with pathologic diagnoses. The hypothesis is that mBosniak classification can stratify the risk of malignancy in children with renal cysts. STUDY DESIGN: Patients treated for cystic renal masses with available imaging and pathology between 2000 and 2019 from five institutions were identified. Clinical characteristics and pathology were obtained retrospectively. Characteristics from the most recent US, CT, and/or magnetic resonance imaging (MRI) were recorded. Reviewers assigned a mBosniak classification to each scan. mBosniak scores 1/2 were considered low-risk and 3/4 high-risk. These groups were compared with pathology (classified as benign, intermediate, malignant). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (+LR), and negative likelihood ratio (-LR) were calculated to assess this categorization as a screening tool to guide surgical intervention. Agreement between imaging modalities was also explored. RESULTS: 99 patients were identified. High-risk imaging findings were correlated with malignant or intermediate pathology with a sensitivity of 88.3%, specificity of 84.6%, PPV of 89.8%, NPV of 82.5%, +LR of 5.7, and -LR of 0.14. The sensitivity for detecting malignant lesions only was 100%. There was substantial agreement between US/CT (n = 55; κ = 0.66) and moderate agreement between US/MRI (n = 20; κ = 0.52) and CT/MRI (n = 13; κ = 0.47). DISCUSSION: The mBos classification system is a useful tool in predicting the likelihood of benign vs. intermediate or malignant pathology. The relatively high sensitivity and specificity of the system for prediction of high-risk lesions makes this classification applicable to clinical decision making. In addition, all malignant lesions were accurately identified as mBosniak 4 on imaging. This study adds substantial data to the relatively small body of literature validating the mBosniak system for risk stratifying pediatric cystic renal lesions. CONCLUSIONS: Pediatric cystic renal lesions assigned mBosniak class 1/2 are mostly benign, whereas class 3/4 lesions are likely intermediate or malignant pathology. We observed that the mBosniak system correctly identified pathology appropriate for surgical management in 88% of cases and did not miss malignant pathologies. There is substantial agreement between CT and US scans concerning mBos classification.