While SPTBN4 did not demonstrate prognostic significance in normal testicular tissues (p = 0.496, HR = 0.78, 95% CI: 0.39–1.578), subgroup analysis revealed that high SPTBN4 expression was associated with poorer prognosis in seminoma patients (p = 0.032, HR = 9.86, 95% CI: 1.217–79.87). This evidence concerns the gene SPTBN4 and seminoma.