Contemporary survival and treatment outcomes in malignant spermatic-cord tumors: A two-decade population-based analysis.

593 Background: Malignant spermatic-cord tumors (SCTs) are exceedingly rare, and population-level survival data in the modern era are limited. Historically, outcomes were limited by incomplete excision and high local recurrence, leading to recommendations for selective adjuvant radiotherapy. With modern imaging and improved histologic classification, presentation patterns and survival may have evolved. This study defines contemporary survival benchmarks and treatment utilization for malignant SCTs in the United States. Methods: The Surveillance, Epidemiology, and End Results (SEER) Program was queried for microscopically confirmed malignant SCTs (primary site C63.1). Analyses were restricted to first matching primaries and excluded autopsy/death-certificate-only records. Cause-specific survival (CSS) was estimated using the Kaplan-Meier method and summarized at 5 and 10 years. Stratifications included age (<40, 40–59, ≥60 years), and diagnosis era (2000–2005, 2006–2011, 2012–2016, 2017–2022). Treatment variables included RX Summ-Surg Prim Site, Radiation recode, and Chemotherapy recode. Results: A total of 403 patients with malignant SCTs were identified. All underwent definitive surgery. Age-specific CSS demonstrated excellent outcomes in younger patients, with 5- and 10-year CSS of 100% and 92.9% for <40 years, 93.6% and 86.9% for 40–59 years, and 87.9% and 83.3% for ≥60 years, respectively. Beam radiation was uncommon but present, with era-specific row percentages of 5.8% (2000–2005), 3.2% (2006–2011), 2.7% (2012–2016), and 3.6% (2017–2022). Chemotherapy use was observed at about 10–15% across eras. Localized-stage cases increased from approximately 55% to 70% over two decades, while regional and distant stages declined, demonstrating modest stage migration toward earlier detection. Stage-specific survival showed the expected prognostic separation (localized > regional > distant). Conclusions: Malignant SCTs achieve durable, near-curative survival with definitive surgery, even at the population level. Consistently high CSS despite minimal adjuvant use highlights that outcomes are driven by complete surgical resection and early detection rather than therapeutic escalation. The rising share of localized-stage cases reflects stage migration from improved imaging and histologic precision. These findings establish the largest and most contemporary national survival benchmarks for this rare malignancy and reinforce the need to optimize margin-negative surgery, early recognition, and age-tailored follow-up to sustain long-term cure and prevent late recurrences.