Development and validation of a nomogram for predicting outcome of patients with vulvar cancer.
OBJECTIVE
To construct and validate a nomogram to predict relapse-free survival of patients treated for vulvar cancer.


METHODS
Data from 244 patients treated for vulvar cancer at a single institution (Creteil, France) were used as a training set to develop and calibrate a nomogram for predicting relapse-free survival and local relapse-free survival. We used bootstrap resampling for the internal validation and we tested the nomogram on an independent validation set of patients (Torino, Italy) for the external validation.


RESULTS
The nomograms were based on a Cox proportional hazards regression model. Covariates for the relapse-free survival model included age, T stage, number of metastatic nodes, bilateral lymph node involvement, omission of the lymphadenectomy, margin status, lymphovascular space invasion, and depth of invasion. The concordance indices were 0.85 and 0.83 in the training set before and after bootstrapping, respectively, and 0.83 in the validation set. The predictions of our nomogram discriminated better than did the International Federation of Gynecology and Obstetrics stage (0.83 compared with 0.78, P = .01). The calibration of our nomogram was good. In the validation set, 2-year and 5-year relapse-free survival were well predicted with less than 5% difference between the predicted and observed survivals for each quartile. A nomogram for predicting local relapse was also developed.


CONCLUSIONS
We have developed nomograms for predicting distant and local relapse of vulvar cancer at 2 and 5 years and validated them both internally and externally. These nomograms will be freely available on the International Society for the Study of Vulvovaginal Disease Web site.


METHODS
III.
Rouzier
Roman
R
Department of Gynecology and Obstetrics, Centre Hospitalier Intercommunal de Créteil, University Paris 12, Créteil, France. rouzierroman@yahoo.fr
Preti
Mario
M
Haddad
Bassam
B
Martin
Michel
M
Micheletti
Leonardo
L
Paniel
Bernard-Jean
BJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D015233:Models, Statistical; D011379:Prognosis; D016896:Treatment Outcome; D014846:Vulvar Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy