Risk factors for distant metastasis and prognosis of the penile cancer with distant metastasis.

Background: Penile cancer (PC) is a rare malignant tumor, whose distant metastasis (DM) is associated with the poorest outcomes. The risk factors associated with DM and prognosis of the PC with DM remain elusive. This study was aimed at investigating risk factors associated with DM and constructing prediction models of PC with DM.

Methods: This study analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database over a period of 2000-2020, including clinical characteristics such as age, marital status, tumor size, Tumor Node Metastasis (TNM) staging, and treatment information. Utilizing univariate and multivariate logistic regression, alongside cox regression analysis, we identified independent risk factors for DM and prognosis in the total cases and the cases with DM. Nomograms were developed for predicting DM and prognosis in PC patients.

Results: Enrolling 1,488 cases, our study identified tumor size and N stage as independent predictors of DM. The predictive nomogram for DM achieved an area under the curve (AUC) of 0.904. Notably, the 1-, 3-, and 5-year cumulative survival rates for PC with DM were 35%, 17%, and 13%, respectively, with larger tumor size associated with prognosis of PC cases with DM. This study verified a correlation between advanced age and TNM stage, as well as chemotherapy with the poor PC prognosis. The nomogram yielded 0.72, 0.69 and 0.69, in predicting 1-, 3-, and 5-year overall survivals (OS), while 0.73, 0.70 and 0.69 in predicting 1-, 3-, 5-year cancer specific survivals (CSS), respectively.

Conclusions: This study investigated risk factors of PC with DM. Also, nomograms for predicting DM, OS and CSS of PC patients were developed.