Sentinel Node Mapping in Penile Cancer: An Update on Methods and Pitfalls

Area of Science:

• Oncology
• Surgical Oncology
• Nuclear Medicine

Background:

• Inguinal lymph node status is critical for penile cancer prognosis.
• Occult metastases occur in 20%-25% of clinically node-negative (cN0) patients.
• Accurate nodal staging is essential for appropriate treatment.

Purpose of the Study:

• To review the dynamic sentinel node biopsy (DSNB) technique for penile cancer staging.
• To discuss variations in DSNB practice and their impact on outcomes.
• To explore innovations and future directions in nodal staging.

Main Methods:

• Review of the DSNB technique, including its multidisciplinary aspects.
• Discussion of management for radio-tracer-silent groins and intraoperative frozen section analysis.
• Exploration of emerging innovations like magnetic nanoparticles and ctDNA analysis.

Main Results:

• DSNB is the current gold standard for cN0 penile cancer nodal staging.
• Reported false-negative rates for DSNB average approximately 12%-13%.
• Fewer than 20% of patients with metastatic sentinel nodes have additional metastases after ILND.

Conclusions:

• Optimizing DSNB is crucial to reduce false-negative rates and morbidity.
• Current guidelines may lead to overtreatment in over 80% of patients undergoing ILND.
• Refining DSNB to better select patients for ILND is a key future goal.