Predict Lymph Node Metastasis in Penile Cancer Using Clinicopathological Factors and Nomograms

Yanxiang Shao; Xiang Tu; Yang Liu; Yige Bao; Shangqing Ren; Zhen Yang; Xu Hu; Kan Wu; Hao Zeng; Qiang Wei; Xiang Li

doi:10.2147/CMAR.S329925

Predict Lymph Node Metastasis in Penile Cancer Using Clinicopathological Factors and Nomograms

Cancer Manag Res. 2021 Sep 24:13:7429-7437. doi: 10.2147/CMAR.S329925. eCollection 2021.

Authors

Yanxiang Shao^#¹, Xiang Tu^#¹, Yang Liu^#¹, Yige Bao¹, Shangqing Ren^{1

2}, Zhen Yang^{1

3}, Xu Hu¹, Kan Wu¹, Hao Zeng¹, Qiang Wei¹, Xiang Li¹

Affiliations

¹ Department of Urology, Institute of Urology, West China Hospital, Sichuan University, Chengdu, People's Republic of China.
² Robotic Minimally Invasive Surgery Center, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, People's Republic of China.
³ Department of Urology, Chengdu Second People's Hospital, Chengdu, People's Republic of China.

^# Contributed equally.

Abstract

Objective: To investigate the predictive factors of lymph node metastasis (LNM) and evaluate the usefulness of prediction nomograms.

Methods: This study included 300 patients diagnosed with penile squamous cell carcinoma at West China Hospital (WCH) of Sichuan University (Chengdu, China) and 412 cases acquired from the Surveillance, Epidemiology, and End Results (SEER) program. Logistic regression analysis was performed on these cohorts to investigate the predictive factors of LNM. We evaluated a recently developed prediction nomogram for LNM, which was established based on the National Cancer Database (NCDB). Moreover, we developed a novel nomogram using cases from the WCH for the prediction of lymphatic metastasis.

Results: Logistic analysis identified that younger age at diagnosis, invasion of the penis body, poorer pT stage, cN stage, nuclear grade and the presence of lymph vascular invasion (LVI) were significantly correlated with LNM in WCH cases; however, only race, poorer T stage and cN stage were significantly associated with LNM among the cases from the SEER. Multivariate analysis demonstrated that younger age, poorer T stage, cN stage and nuclear grade were independent predictors of LNM. Receiver operating characteristic curve analysis of WCH cases showed that the tumor T stage 8th edition has better area under the curve than 7th stage (0.672 vs 0.636, respectively). Moreover, well AUC was seen in external validation of NCDB nomogram in WCH cohorts and SEER series (0.833 vs 0.795). The new nomogram included the aforementioned independent predictors and the bootstrap-corrected concordance was 0.876.

Conclusion: Younger diagnose age, poorer pT stage, cN stage, nuclear grade and LVI were the most important predictors of LNM in patients with penile cancer. 8th T stage performed better than 7th version in predicting LNM. NCDB nomogram has some application values in both WCH and SEER cases, and our novel model further improved the predictive accuracy.

Keywords: SEER; lymph node metastasis; nomogram; penile cancer; prediction model.

Grants and funding

This study was supported by the National Natural Science Foundation of China (Reference Number: 81672552), the Science and Technology Foundation of Sichuan Province (2017JY0226) and the 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University (Reference number: ZY2016104).