PURPOSE: Several phase II trials have investigated the efficacy of retroperitoneal lymph node dissection (RPLND) with unilateral modified template as the first-line treatment for stage II seminoma. However, the rationale for using modified templates is extrapolated from studies of non-seminomatous germ cell tumor (NSGCT). In this retrospective study, we sought to compare the oncologic outcome of bilateral and unilateral templates, and perform a clinical mapping study for metastatic seminoma. MATERIALS AND METHODS: Patients who presented with pure seminoma at orchiectomy, retroperitoneal only metastasis either at presentation or relapse, and underwent primary RPLND from 2016 to 2022 at our institution were reviewed. Pathologic and clinical outcomes were compared after stratification based on dissection templates. RESULTS: The cohort included 104 patients with 36 unilateral and 68 bilateral template dissection. The two-year RFS was 80.6% for the unilateral group and 86.8% for the bilateral group. Among the recurrences, 66.7% and 90% were outside of the retroperitoneum in unilateral and bilateral group, respectively. The most common landing zones of metastatic seminoma are para-aortic for left and interaortocaval for right sided primary tumors. The microscopic metastasis in the contralateral zones ranges from 6-11.1%. CONCLUSIONS: The most common landing zones of seminoma mirror NSGCT. Primary RPLND provides excellent oncologic outcomes for early stage II seminoma. In the early experience in stage II seminoma we have favored bilateral template dissections. More data is needed to better understand if bilateral templates should be uniformly performed in pure seminoma.