Impact of hospital case volume on testicular cancer outcomes and practice patterns.

BACKGROUND: Given the rarity of testicular germ cell tumors (TGCTs) and the complex aspects of management, we evaluate the effect of hospital TGCT case volume on overall survival outcomes and practice patterns.

MATERIALS AND METHODS: The National Cancer Database was queried for patients diagnosed with seminoma or nonseminomatous germ cell tumor (NSGCT). Hospitals were classified by case volume as high (99th percentile, ≥26.1 cases annually), high-intermediate (95-99th percentile, 14.6-26.0 cases annually), intermediate (75-95th percentile, 6.1-14.5 cases annually), low-intermediate (25-75th percentile, 1.8-6.0 cases annually), and low (25th percentile,<1.8 cases annually). The median (interquartile range) number of TGCT cases per institution per year was 3.4 (1.8-6.1).

RESULTS: A total of 33,417 patients with TGCT diagnosed from 1,239 institutions met inclusion criteria. Despite worse disease characteristics of patients treated at higher volume institutions, hospital volume was positively associated with survival outcomes in more advanced cases of TGCT. In the overall cohort, compared to the high-volume hospitals, patients treated at high-intermediate, intermediate, low-intermediate, and low volume hospitals the hazard ratio for overall mortality was 1.28, 1.45, 1.48, and 1.83, respectively (P<0.05). The association between survival and hospital volume was not apparent for seminoma or stage I NSGCT. Patients treated at higher volume hospitals were more likely to undergo surveillance for stage I seminoma, primary retroperitoneal lymph node dissection (RPLND) for stage I NSGCT, and postchemotherapy RPLND for stage II/III NSGCT.

CONCLUSIONS: Our analysis of a nationwide cancer registry demonstrated that increased hospital TGCT case volume was associated with significant differences in management strategies and improved survival outcomes, in particular for more advanced disease.