Retroperitoneal Nodal Distribution for Metastatic Seminoma: Is Modified Template Appropriate? A Retrospective Study.

Area of Science:

• Urology
• Oncology
• Surgical Oncology

Background:

• Retroperitoneal lymph node dissection (RPLND) is a treatment for stage II seminoma.
• Modified templates for RPLND are often based on nonseminomatous germ cell tumor data.
• The optimal template for seminoma requires further investigation.

Purpose of the Study:

• To compare oncologic outcomes between unilateral and bilateral RPLND templates in stage II pure seminoma.
• To perform a clinical mapping study of metastatic seminoma patterns.

Main Methods:

• Retrospective review of 104 patients with stage II pure seminoma undergoing primary RPLND (2016-2022).
• Patients stratified by unilateral (n=36) vs. bilateral (n=68) template dissection.
• Comparison of recurrence-free survival and metastatic sites.

Main Results:

• The 2-year recurrence-free survival was 80.6% for unilateral and 86.8% for bilateral templates.
• Recurrences outside the retroperitoneum were 66.7% (unilateral) and 90% (bilateral).
• Common metastatic sites include para-aortic and interaortocaval regions; microscopic contralateral metastasis observed (6-11.1%).

Conclusions:

• Primary RPLND offers excellent outcomes for stage II seminoma.
• Metastatic patterns in seminoma resemble nonseminomatous germ cell tumors.
• Bilateral templates may offer advantages, but further data are needed to determine uniform applicability.