Dynamic sentinel node biopsy for penile cancer: an initial experience in an Irish Hospital

The presence of nodal metastases is the single most important prognostic factor in penile cancer. However, reliable assessment of nodal status in clinically node-negative (cN0) patients poses a challenge. Approximately 20% of these patients harbour occult nodal metastases. Currently available non-invasive radiological investigations are unreliable in excluding micrometastatic disease.

Dynamic sentinel node biopsy (DSNB) is a minimally invasive procedure for assessing lymph node involvement. We report our initial experience with DSNB in assessing the status of regional lymph nodes in cN0 penile cancer patients.

DSNB was performed in penile cancer patients with at least one cN0 groin. All patients undergoing DSNB at our institution were included. Lymphoscintigraphic images were obtained from all patients, after intradermal, peritumoral injection of a Technetium-99m nanocolloid. The sentinel nodes were defined as the nodes identified on lymphoscintigraphy, which were also radioactive intraoperatively using a gamma probe.

In total, 18 groins from 11 patients underwent DSNB. Of these, 11 patients underwent bilateral DSNB and 4 had unilateral DSNB. The mean (range) age of patients at the time of presentation of their primary tumour was 63 (39-78) years. A mean of 1.2 nodes per groin was retrieved. One lymph node was positive in one patient, who subsequently underwent a bilateral inguinal lymph node dissection. Overall, the median (range) follow-up was 12.8 (2.7-31.3) months with no local or regional recurrences.

Further cases and longer follow-up will define the accuracy of this technique in the Irish population.