Retroperitoneal lymph node dissection (RPLND) is gaining traction as a primary treatment option for early-stage II seminoma, offering an alternative to systemic chemotherapy and radiation, which are associated with long-term side effects. Recent studies and guideline updates from the American Urological Association (AUA) and National Comprehensive Cancer Network (NCCN) support the use of RPLND in select patients, particularly those with low-stage metastatic seminoma.
Efficacy of Primary RPLND
Data from three prospective trials—SEMS, PRIMETEST, and COTRIMS—pooling 118 patients, demonstrate that RPLND achieves a 2-year recurrence-free survival (RFS) rate of approximately 70% to 90% without the need for adjuvant therapy. A retrospective study at Indiana University (IU) reported a 2-year RFS rate of 82% in 67 patients. These findings have led to the inclusion of primary RPLND as a treatment option in the AUA and NCCN guidelines for testicular cancer.
Cary, the director of the Urologic Germ Cell Tumor Program at Indiana University School of Medicine, notes that patients initially presenting with stage I seminoma who develop retroperitoneal metastasis after 12 months are more likely to be cured by RPLND alone.
Recurrence and Salvage Therapy
Surveillance post-RPLND is crucial, as most recurrences (over 80%) occur within the first two years. Recurrences can manifest in various locations, including the retroperitoneum, pelvis, mediastinum, and supraclavicular region. Systemic chemotherapy, typically involving 3 cycles of bleomycin, etoposide, and cisplatin (BEP) or 4 cycles of etoposide and cisplatin (EP), is highly effective in eradicating recurrent disease. In select cases with localized pelvic recurrence, repeat surgery, such as pelvic lymph node dissection (LND), may be considered.
Lymph Node Mapping and Template
The RPLND template is currently based on mapping studies of nonseminomatous germ cell tumors (NSGCTs). Given that pure seminoma primarily metastasizes through the lymphatic system, the lymphatic drainage patterns are expected to mirror those of NSGCTs in the retroperitoneum. Unpublished data from Indiana University suggests that the primary retroperitoneal landing zone is para-aortic for left-sided tumors and interaortocaval (IAC) for right-sided tumors.
Crossover, defined as microscopic positive nodal deposition in the IAC zone for left-sided tumors and the para-aortic zone for right-sided tumors, has been observed in 5% to 11% of patients. This rate appears higher than in NSGCTs, potentially due to the study cohort being limited to stage II seminoma with minimal pN0 disease. Bilateral template dissections are currently performed at Indiana University for all stage II seminoma patients until further data clarifies nodal drainage patterns.
Complications and Recovery
RPLND has a favorable safety profile, with a 30-day complication rate of 4.5% at Indiana University. Most complications are mild, such as ileus. Implementation of enhanced recovery after surgery (ERAS) protocols has reduced the median length of stay to 3 days, significantly shorter than the historical average of 6 days. Chylous ascites remains a potential complication, with an incidence of 1.9%, comparable to primary RPLND in NSGCTs.
Masterson, an associate professor of urology at Indiana University School of Medicine, emphasizes the importance of offering RPLND as an option in high-volume centers with experienced surgeons.
