[Independent external verification of the nomograms for predicting lymph node metastasis in penile cancer].

Objective: To evaluate the two newly established nomograms for predicting lymph node metastasis in penile cancer based on the clinical data on a large cohort of patients. METHODS: We retrospectively studied the clinical data on 93 patients with penile cancer treated in the Center for Tumor Prevention and Treatment. Using the two recently established nomograms (Bhagat nomogram and Zhu nomogram), we predicted lymph node metastasis in the patients, analyzed the differences between prediction and the results of postoperative pathology, and compared the accuracy of prediction between the two nomograms with the receiver operating characteristic (ROC) curve and the area under the curve (AUC). RESULTS: The median age of the patients was 55 (27－82) years. Positive lymph nodes were found in 31 cases (33.3%) postoperatively and in 9 (21.9%) of the 41 clinically negative cases. The AUC of the Bhagat nomogram was 0.739 and that of Zhu nomogram was 0.808, both of which were similar to the prediction accuracy of internal verification and manifested a medium predictive ability. CONCLUSIONS: The newly established Bhagat and Zhu nomograms can be used for predicting lymph node metastasis in penile cancer, but with a low precision, and therefore cannot be relied exclusively for the option of inguinal lymphadenectomy.