Validation of predictors for lymph node status in penile cancer: Results from a population-based cohort

  • X. Melody Qu Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital
  • D. Robert Siemens Queen's University
  • Alexander V. Louie Western University, London Health Sciences Centre
  • Darwin Yip Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital
  • Aamer Mahmud Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital

Abstract

Introduction: The ability to predict lymph node (LN) status is essential in the management of men with localized squamous cell carcinoma (SCC) of the penis. There has been limited external validation of available risk stratification tools, particularly in routine clinical care. The objective of this study was to evaluate the predictive variables of LN metastases within a large population-based cohort of patients.

Methods: In this population-based cohort study, surgical pathology reports were linked to the population-based Ontario Cancer Registry to identify all patients who were diagnosed with penile cancer in Ontario, Canada. Multivariable analyses were performed to evaluate predictive variables for LN involvement. Three contemporary risk stratification schemes used to predict LN status were analyzed by logistic regression.

Results: The study included 380 localized penile SCC cases treated between 2000 and 2010. Sixty-three (17%) had pathologically confirmed LN metastases. Among these, 35 (56%) were diagnosed within three months of the initial penile SCC diagnosis and these patients had a worse five-year disease-specific survival (43%; 95% confidence interval [CI] 26–64) compared to patients who were diagnosed at a delayed LN dissection. On multivariable analysis, age (odds ratio [OR] 0.68; 95% CI 0.52–0.88), pathological stage (≥pT1b; OR 3.32; 95% CI 1.38–8.01), and tumour grade (Grade 2 OR 2.98; 95% CI 1.26–7.62; Grade 3 OR 3.97; 95% CI 1.32–11.9) were associated with an increased risk of LN metastases. Candidate risk stratification schemes demonstrated moderate to good property, with C-statistics ranging from 0.662–0.747.

Conclusions: Using a population-based cohort of penile cancer patients with a relatively low proportion of patients with pathologically confirmed LN involvement, we confirm and externally validate the importance of age, stage, and grade of the primary tumour in predicting nodal status.

Author Biographies

X. Melody Qu, Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital

Department of Oncology

D. Robert Siemens, Queen's University
Department of Urology
Alexander V. Louie, Western University, London Health Sciences Centre
Department of Radiation Oncology
Darwin Yip, Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital
Department of Oncology
Aamer Mahmud, Queen's University Cancer Centre of Southeastern Ontario at Kingston General Hospital
Department of Oncology
Published
2017-12-16
How to Cite
Qu, X. M., Siemens, D. R., Louie, A. V., Yip, D., & Mahmud, A. (2017). Validation of predictors for lymph node status in penile cancer: Results from a population-based cohort. Canadian Urological Association Journal, 12(4), 119-25. https://doi.org/10.5489/cuaj.4711
Section
Original Research