SUO 2017: Impact of Hospital Case Volume on Testicular Cancer Outcomes and Practice Patterns

Washington, DC ( Dr. Woldu and colleagues presented their results of a study assessing the impact of hospital case volume on testicular cancer outcomes. For other complex procedures, for example abdominal aortic aneurysm repair, Whipple procedure and radical cystectomy, there has been a call for centralization of these procedures to tertiary centers of excellence. Given the rarity of testicular germ cell tumors (TGCTs) and the complex aspects of management, the objective of this study was to evaluate the impact of hospital TGCT case volume on overall survival (OS) outcomes and practice patterns.

The authors used the National Cancer Database (NCDB) to query for patients diagnosed with seminoma or non-seminomatous 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 (25th-75th percentile, 1.8-6.0 cases annually), and low (25th percentile, <1.8 cases annually). The median (IQR) number of TGCT cases per institution per year was 3.4 (1.8-6.1). 

There were 33,417 patients with TGCT diagnosed from 1,239 institutions that met inclusion criteria. Low, low-intermediate, intermediate, high-intermediate, and high-volume hospitals accounted for 5.0%, 36.8%, 35.6%, 15.9%, and 6.8% of the cases, respectively. As such, the highest volume hospitals took care of a disproportionate number of patients with the top 5% of hospitals by case volume caring for 22.7% of all patients. 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). A statistically significant 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 post-chemotherapy RPLND for stage II/III NSGCT.

Dr. Woldu concluded that based on this analysis of a nationwide cancer registry, increased hospital TGCT case volume was associated with significant differences in management strategies and improved survival outcomes, in particular for more advanced disease. Particularly for patients with >stage 1 NSGCT, they should be referred to tertiary centers of excellence in order to receive appropriate treatment and ongoing post-treatment surveillance. 

Presented by: Solomon L. Woldu, MD

Co-Authors: Justin Matulay MD², Nirmish Singla MD¹, Timothy Clinton MD¹, Laura-Maria Krabbe MD¹, Ryan Hutchinson MD¹, Yuval Freifeld MD¹, Arthur Sagalowsky MD¹, Yair Lotan MD¹, Vitaly Margulis MD¹ and Aditya Bagrodia MD¹

Affiliation: ¹UT Southwestern Medical Center ; ²Columbia University Medical Center NY, NY

Written by: Zachary Klaassen, MD, Society of Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre @zklaassen_md at the 18th Annual Meeting of the Society of Urologic Oncology, November 20-December 1, 2017 – Washington, DC