Exploring Stage I non-small-cell lung cancer: development of a prognostic model predicting 5-year survival after surgical resection†.
OBJECTIVE
Despite impressive results in diagnosis and treatment of non-small-cell lung cancer (NSCLC), more than 30% of patients with Stage I NSCLC die within 5 years after surgical treatment. Identification of prognostic factors to select patients with a poor prognosis and development of tailored treatment strategies are then advisable. The aim of our study was to design a model able to define prognosis in patients with Stage I NSCLC, submitted to surgery with curative intent.


METHODS
A retrospective analysis of two surgical registries was performed. Predictors of survival were investigated using the Cox model with shared frailty (accounting for the within-centre correlation). Candidate predictors were: age, gender, smoking habit, morbidity, previous malignancy, Eastern Cooperative Oncology Group performance status, clinical N stage, maximum standardized uptake value (SUV(max)), forced expiratory volume in 1 s, carbon monoxide lung diffusion capacity (DLCO), extent of surgical resection, systematic lymphadenectomy, vascular invasion, pathological T stage, histology and histological grading. The final model included predictors with P < 0.20, after a backward selection. Missing data in evaluated predictors were multiple-imputed and combined estimates were obtained from 10 imputed data sets.


RESULTS
Analysis was performed on 848 consecutive patients. The median follow-up was 48 months. Two hundred and nine patients died (25%), with a 5-year overall survival (OS) rate of 74%. The final Cox model demonstrated that mortality was significantly associated with age, male sex, presence of cardiac comorbidities, DLCO (%), SUV(max), systematic nodal dissection, presence of microscopic vascular invasion, pTNM stage and histological grading. The final model showed a fair discrimination ability (C-statistic = 0.69): the calibration of the model indicated a good agreement between observed and predicted survival.


CONCLUSIONS
We designed an effective prognostic model based on clinical, pathological and surgical covariates. Our preliminary results need to be refined and validated in a larger patient population, in order to provide an easy-to-use prognostic tool for Stage I NSCLC patients.
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy francesco.guerrera@outlook.com.
Francesco
F
Guerrera
Departement of Oncology, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Luca
L
Errico
Unit of Cancer Epidemiology and CPO Piedmont, San Giovanni Battista Hospital, Turin, Italy.
Andrea
A
Evangelista
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Pier Luigi
PL
Filosso
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Enrico
E
Ruffini
Departement of Oncology, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Elena
E
Lisi
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Giulia
G
Bora
Departement of Oncology, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Elena
E
Asteggiano
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Stefania
S
Olivetti
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Paolo
P
Lausi
Departement of Oncology, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Francesco
F
Ardissone
Departement of Thoracic Surgery, San Giovanni Battista Hospital, University of Torino, Turin, Italy.
Alberto
A
Oliaro
D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality* / Q000601:surgery*; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality* / Q000601:surgery*; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012306:Risk
Early stage; NSCLC; Non-small-cell lung cancer; Prognostic factors; Staging; Surgery; Survival