Malignant Leydig cell tumor: A population-level demographic study using the National Cancer Database.

Abstract

e17010 Background: Leydig cell tumors (LCTs) are typically rare testicular neoplasms arising from androgen-producing interstitial cells and account for 1–3% of testicular tumors. Although most cases are benign, a subset malignantly transforms, and the resulting mortality increases sharply, with many patients dying within two years. Malignant LCTs respond poorly to platinum-based chemotherapy and radiation, and metastasectomy rarely achieves lasting disease control. Given the rarity of malignant LCTs, demographic and epidemiological data are limited, and population-level patterns remain poorly defined. This study used the National Cancer Database (NCDB) to further characterize demographic trends in malignant LCT. Methods: A retrospective cohort study from the NCDB identified patients with histologically confirmed malignant LCT (ICD-O-3 Code 8650) from 2004–2020 (N = 526). Demographic variables were analyzed, including age, sex, race, ethnicity, education, insurance, facility type, residential distance, tumor size, stage, treatment, education status, income, and Charlson–Deyo score. Incidence trends were evaluated using regression analysis and descriptive statistics. Results: A total of 526 cases were identified. Incidence showed moderate variability with no consistent trend (R² = 0.50). The cohort was overwhelmingly male (95%), predominantly White (74.7%), and largely non-Hispanic (87.8%), with a mean age of 47.6 years. An atypical percentage of patients lived in metropolitan counties with ≥1 million population (54.1%) and were concentrated in the highest income (≥ $74,063; 42.6%) and education quartiles ( < 5% without a high school degree; 28.5%). Treatment most commonly occurred in comprehensive community cancer programs (39.3%) or academic/research programs (38.2%), and private insurance was the primary payer for 61.6% of patients. Early mortality was rare (0.4% at 30 days; 0.6% at 90 days). Almost all patients (99.8%) received no palliative care. Surgery was the primary treatment, with 92.8% achieving negative margins; nonsurgical therapies were uncommon (radiation 2.7%, chemotherapy 3.2%, hormone therapy 1.0%, immunotherapy 0.4%). Tumors averaged 30.6 mm in size, and most were NCDB Analytic Stage I (70.7%). Mean survival was 165.4 months, with estimated two, five, and 10-year survival rates of 92.0%, 87.0%, and 79.0%. Conclusions: To our knowledge, this is the first NCDB analysis focused on malignant LCT, addressing a major gap in the epidemiologic characterization. Unlike prior reports, these cases occurred predominantly in middle-aged men in the early stages. This study provides the first nationwide description of socioeconomic patterns, demonstrating concentration in high-income, educated urban populations. Further research is needed to determine how demographic and socioeconomic factors shape diagnostic timing, treatment selection, and long-term outcomes.