Inguinal lymph node dissection for penile cancer: Predictors of lymph node metastasis.

Abstract

386 Background: Inguinal lymph node dissection (ILND) for lymph node metastasis (LNM) of squamous cell carcinoma of the penis (SCCP) can be a curative surgical treatment. Having the potential to identify clinical and pathological factors that predict LNM is important because of the poor prognosis this diagnosis carries. Methods: A retrospective review of 51 patients that underwent inguinal plus pelvic lymph node dissection from 1999 to 2012 was preformed. Age, race, body mass index (BMI), significant lymphadenopathy on preoperative imaging (nodes > 1 cm), palpable lymphadenopathy, and pathologic depth of invasion and diameter of the primary penile tumor along with associated lymphovascular invasion (LVI) were recorded and analyzed as potential predictors of LNM. Results: Median patient age was 65 and the median BMI was 29.3. Thirty-nine patients (76.5%) were white, 3 (5.9%) African American, and 9 (17.6%) were Hispanic. Median primary penile tumor diameter was 3.2 cm with 7, 29, and 15 patients having well, moderate, and poorly differentiated tumors. Pre-operatively, 32 patients (62.7%) had palpable lymphadenopathy on physical exam and 26 (51.0%) had significant lymphadenopathy on imaging (93% CT, 7% MRI), with 24 (47.1%) having both findings. Thirty-one patients (60.8%) who underwent ILND had pathological LNM. On univariate analysis, palpable nodes (p < 0.001), nodes on imaging (p <0.001), having both palpable nodes and nodes on imaging (p < 0.001), age (p = 0.02), and LVI (p = 0.04), were significantly associated with LMN. On multivariate analysis, having nodes on imaging (p = 0.001) and age < 65 years (p = 0.049) were significant for predicting LNM. Conclusions: In evaluation of patients with T1-T3 penile cancer, multiple factors were predictive of LNM in our series: palpable and radiographic nodes, younger than age 65 and LVI. Inguinal adenopathy defined as more than 1 cm appears to better predict occult nodal metastasis, however, this must be weighed in terms of the additional cost and clinical yield provided by widespread adoption of pelvic (CT or MRI) imaging in all patients with aggressive primary penile tumor phenotypes.