Background: Long-term relative survival (RS) data for testicular germ cell tumor (TGCT) patients are scarce. We aimed to analyze long-term RS among TGCT patients diagnosed in Norway, between 1953 and 2012.Methods: Data sources were the Cancer Registry of Norway and the Norwegian Cause of Death Registry. TGCT patients diagnosed during 1953 to 2012 were classified by time of diagnosis, histology, age, and disease extent at diagnosis. Estimates for RS were obtained, and a test comparing overall RS was performed. Corresponding data were obtained for men diagnosed with localized malignant melanoma before age 50.Results: A total of 8,736 TGCT patients were included. RS generally continued to decline with increasing follow-up time, particularly beyond 15 to 30 years, unlike in localized malignant melanoma. Although RS was generally higher for seminomas, the continuing decline was more pronounced than for nonsemino-