Chest CT in Testicular Mass Evaluation: A Stepwise Approach to Minimize Radiation Exposure

Chest computed tomography (CT) is commonly obtained for initial staging of testicular cancer. Since pulmonary metastases are rare in the absence of retroperitoneal disease or elevated tumor markers, a selective imaging approach may be justified, as routine chest CT can lead to unnecessary radiation exposure to the thorax.

We conducted a retrospective cohort study of men evaluated for a newly diagnosed testicular mass at a tertiary medical center between 2011 and 2025. According to institutional protocol, all patients underwent abdominal and chest CT prior to radical orchiectomy. A risk-stratified approach was then assessed, assuming that chest CT would have been omitted if both serum tumor markers and abdominal CT were negative for metastasis. The primary outcome was the false-negative rate for thoracic metastases among patients who would have been triaged to omit chest CT, and the key secondary outcome was the proportion of chest CT examinations that could have been avoided.

Among 183 eligible patients (mean age 34.3 ± 11.1 years), 174 (95.0%) had germ-cell tumors, including 107 (61.4%) seminomas. Chest metastases were identified in 10 patients (5.5%). Nine (90%) had positive tumor markers and seven (70%) had retroperitoneal nodal involvement. Using the prespecified rule (perform chest CT if either markers or retroperitoneal nodes were abnormal), no metastatic cases would have been missed, yielding sensitivity 100% (95% confidence interval [CI]: 69.2-100.0) and negative predictive value: 100.0% (95% CI: 95.7-100). Specificity was 48.0% (95% CI: 40.3-55.7), and application of the rule would have avoided 45.4% (95% CI: 38.0-52.9) of chest CTs.

Integrating serum tumor markers with abdominal CT before deciding on chest CT may safely reduce radiation exposure without compromising diagnostic accuracy in the workup of men with a testicular mass. External validation is warranted before clinical implementation.