Development and validation of nomograms predicting cancer‐specific survival of vulvar cancer patients: based on the Surveillance, Epidemiology, and End Results Program

Abstract

Objective: To explore potential prognostic factors and develop nomograms to predict the cancer-specific survival of patients with vulvar squamous cell carcinoma (SCC) and patients with vulvar melanoma. Methods: Cases of vulvar SCC and melanoma were retrieved from the Surveillance, Epidemiology, and End Results (SEER) Program, and randomly segregated into training and test sets. Based on the training set, univariate and multivariate Cox proportional hazard regressions evaluate the association between key demographic/clinical characteristics and vulvar cancer survival. Potential prognostic factors were included to construct nomograms for the prediction of 3-year and 5-year survival probabilities. Results: Age, tumor size, stage, surgery, and chemotherapy were potential factors associated with vulvar cancer survival. The C-indices for the training and test sets were 0.82 and 0.81 for SCC, and 0.73 and 0.70 for melanoma. Calibration curves revealed correlated agreements between nomogram-based probability and actual survival status. Conclusion:Nomograms were developed to predict cancer-specific survival of patients with vulvar cancer, accordingly identifying the subgroup at high risk of cancerspecific mortality.

Developing and Validating Novel Nomograms for Predicting the Overall Survival and Cancer-Specific Survival of Patients With Primary Vulvar Squamous Cell Cancer

“…In line with previous studies, our model comprises age, tumor size, pathologic grade, radiotherapy, chemotherapy, surgery, and M stage, which were significant factors associated with CSS and included in the previously generated nomograms ( 9 , 10 , 14 ). Moreover, the FIGO stage was not included in our final model, although it was the most prevalent stage system for gynecological cancers, similar to two studies ( 9 , 10 ).…”

“…The DCA plot was shown in Figures 2, 3. Compared with the previously published nomograms with the best accuracy for CSS prediction (14), our model has the larger net benefit.…”

“…Moreover, the FIGO stage was not included in our final model, although it was the most prevalent stage system for gynecological cancers, similar to two studies ( 9 , 10 ). The invasion depth and N stage were also included in the final model, which has been argued as an essential prognostic factor of VSCC ( 9 , 10 ) but not included in a more recently published nomogram ( 14 ). The inclusion of radiotherapy tended to be associated with improved survival; although it is not significant in the final model, the addition of it increased the prediction accuracy of the model, contrary to a recent study in which radiotherapy was negatively associated with VSCC ( 14 ).…”

“…Some studies even found that margin status was not associated with survival, probably due to the hardship of identifying margin status (11)(12)(13). A recently developed study comprising age, tumor size, pathological stage, metastasis, radiotherapy, chemotherapy, and surgery had a prediction accuracy of C-statistics of 0.81 for CSS prediction, without considering the invasion depth, SLNB, and N stage (14). Moreover, no nomograms have been developed to predict the overall survival (OS) of the patients with VC.…”

Prognostic nomograms to predict overall survival and cause specific death in vulvar squamous cell carcinoma

“…Although the nomogram was superior to FIGO staging alone, it was only applicable to postoperative patients. Recently, Liu and Wang constructed a cancer specific death nomogram for vulvar cancer patients based on age, tumor size, stage, metastases, surgery, chemotherapy, and radiation 18. In this study, we relied on more detailed variables and done the analysis on both cancer specific death and overall survival in vulvar cancer patients.…”