CHICAGO, IL USA (UroToday.com) - Advances in treatment have improved survival outcomes among men with metastatic testicular germ cell tumors (TGCTs). These advances include the use of cisplatin-based combination chemotherapy, and retroperitoneal lymph node dissection (RPLND) for persistent retroperitoneal masses after chemotherapy. Whether these treatments have truly been adopted and implemented broadly throughout the US has not been documented. Additionally, whether variability in experience with these and other treatments impacts patient outcomes is unknown. The investigators hypothesized that there would be an association between survival and hospital facility volume among men with stage III metastatic TGCT treated at high- or low-volume centers.
They used the National Cancer Data Base (NCDB) to determine whether survival among men with clinical stage III testicular germ cell tumors varied by volume of the center in which they were treated. They identified all men diagnosed with clinical stage III TGCT between 1998 and 2011 within the database. They included only men who were clinical stage III at presentation, and who were treated with chemotherapy, with the intent to assure that patients were treated in a similar way and could be expected to have similar survival outcomes. They defined “hospital volume” by the number of TGCTs diagnosed at each institution, each year, and created four groups by age of diagnosis. They then used Kaplan-Meier and Cox regression to evaluate the relationship between overall survival and hospital volume.
This study included 79 119 patients diagnosed with NGCT overall, but focused the analyses on 8 205 men who were diagnosed with clinical stage III disease. The median age at the time of diagnosis was 32, and the median length of follow-up was 5.7 years. The investigators determined that patients were most frequently seen in “comprehensive” hospitals (47.3% of men), followed by academic hospitals (10.0%), and least frequently in community settings (10.0%). In total, 1 295 men underwent RPLND (15.8% of patients) after chemotherapy.
In terms of the centers where these patients were treated, the number of cases of NGCT diagnosed varied extensively by site. The median number of NGCT cancers seen in a given institution was 8, but this ranged from 1-115 cases. Almost 25% of patients died during the study (1 225 patients, 24.8%). Overall survival at 5-years varied by hospital volume, at 74.3% in a low-volume center and 86.1% in a high-volume center. The authors note that the “greatest disparity for risk of death was recorded between the highest and lowest volume centers (HR: 0.85, p=0.003).”
In this retrospective analysis of the NCDB, overall survival among men with clinical stage III NGCT appeared to be longer when men were treated at high-volume centers as compared to treatment at low-volume centers. Although hypothesis generating, it is difficult to truly rely completely on this data as the authors did not explicitly state whether potentially critical covariates of interest (age, education status, socioeconomic status, to name a few) were (or could be) included in the analysis. It does raise the important point that differing levels of experience among providers and treatment teams, as well as resource availability, may affect patient outcomes in a very real way.
Presented by Claudio Jeldres, MD, MSc at the American Society of Clinical Oncology (ASCO) 50th Annual Meeting - May 30 - June 3, 2014 - Chicago, Illinois USA
Fred Hutchinson Cancer Research Center, Seattle, WA USA
Written by Alicia K. Morgans, MD, assistant professor of medicine and medical oncologist at Vanderbilt-Ingram Cancer Center, and medical writer for UroToday.com