Management and outcomes of clinical stage IIA/B seminoma: Results from the National Cancer Data Base 1998-2012

Abstract

Purpose/objective: Disease-specific survival for testicular seminoma approaches 100%, even for those with node-positive disease. We sought to describe modern practice patterns, survival outcomes, and factors associated with postoperative therapy for patients with clinical stage (CS) IIA/B disease.

Methods and materials: Data on patients diagnosed with CS IIA/B seminoma from 1998 to 2012 were extracted from the National Cancer Data Base. Demographic, clinical, treatment, and payer characteristics were evaluated using multivariate regression to identify factors associated with receipt of chemotherapy or radiation therapy (RT) within 6 months of orchiectomy. Five-year Kaplan-Meier overall survival (OS) by CS and treatment was calculated. A Cox proportional hazards regression for 5-year OS was performed.

Results: A total of 1885 patients were included; 38.5% received chemotherapy and 61.5% received RT. On multivariate analysis, factors associated with receipt of postorchiectomy RT rather than chemotherapy included CS IIA (odds ratio [OR], 3.04; P < .01) and community treatment setting (OR, 1.81-2.76; P < .01). Reduced likelihood of receiving RT was associated with Medicaid insurance (OR, 0.50; P < .01), more recent year of diagnosis (continuous OR, 0.93; P < .01), and primary pathologic tumor 3/4 stage (OR, 0.47; P < .01). On multivariate Cox regression, decreased 5-year OS was associated with receipt of chemotherapy in CS IIA patients (hazard ratio, 13.33; P < .01) but not in CS IIB patients (hazard ratio, 1.39; P = .45). For CS IIA, 5-year OS was 99.4% for orchiectomy and RT versus 91.2% for orchiectomy and chemotherapy (log-rank P < .01). For CS IIB, 5-year OS was 96.1% for orchiectomy and RT versus 92.8% for orchiectomy and chemotherapy (log-rank P = .08).

Conclusions: Consistent with national guideline recommendations, our analysis supports preferred status for RT in CS IIA. In addition, these data also support use of RT for CS IIB. CS, treatment year, primary pathologic tumor stage, insurance, and facility type were associated with type of postoperative therapy. Longer follow-up to account for potential late effects of treatment is needed.