Long-Term Follow-Up of the Reliability, Accuracy, and Morbidity of Dynamic Sentinel Lymph Node Biopsy in Patients with Intermediate- and High-Risk Penile Cancer and Clinically Negative Lymph Node Status

Objectives: The aim of this study was to evaluate the reliability, accuracy, and morbidity of dynamic sentinel lymph node biopsy (DSNB) in patients with intermediate- and high-risk penile cancer who had clinically negative lymph nodes, with a focus on long-term follow-up outcomes. Methods: Between January 2005 and January 2024, 287 patients with histologically confirmed penile cancer underwent radioisotope-guided DSNB at the Department of Urology, University of Pécs. Patients lost to follow-up within 24 months were excluded. Of the remaining patients, 211 underwent primary DSNB and 37 secondary DSNB. Thirty-nine patients in the primary DSNB group with Tis, T1a, or G1 tumours were additionally excluded, leaving 209 patients for analysis. Variables included tumour stage and grade, sentinel lymph node (SLN) yield and histology, complications, inguinal progression, false-negative rate, and radical lymphadenectomy findings. Results: A total of 573 SLNs were removed from 209 patients, with a median of 2.7 nodes per patient. SLN metastases were identified in 31 patients, involving 37 groins. Among 178 patients with negative SLNs, three developed inguinal metastases. Sensitivity was 91% per patient and 92.5% per groin, with false-negative rates of 8% and 7.5%, respectively. All false-negative cases occurred within two years, with no later inguinal recurrences. DSNB-related complications occurred in 24 patients (11.4%); most were mild or moderate and managed on an outpatient basis. Two patients required surgery and one required hospital readmission. Conclusions: In a high-volume centre, DSNB is a safe and reliable staging procedure with low morbidity in clinically node-negative intermediate- and high-risk penile cancer. Further studies should assess radiotracer injection sites and compare one-day versus two-day protocols.