Prognostic value of symptoms at lung cancer diagnosis: a three-year observational study

Abstract

Background: Lung cancer is mainly diagnosed at advanced or locally advanced stages, usually when symptoms become evident. However, sometimes it may be diagnosed incidentally during routine care, while patients are still asymptomatic. Prognosis differences based on symptomatic presentation have been partially explored. Our aim was to analyze the prognostic value of the initial symptomatic state of the patients in a general lung cancer cohort.

Methods: Observational ambispective study including patients consecutively diagnosed with primary lung cancer between January 2016 and December 2018 via the lung cancer Fast Diagnostic Track (FDT). Patients were followed up until death or the end of the study in September 2019. Asymptomatic patients were compared with patients presenting symptoms. Overall survival (OS) of both groups was compared using the log-rank test. Cox regression analysis was performed to clarify the effect of the symptomatic status at diagnosis on survival. Additionally, propensity score (PS) matching analysis was performed.

Results: A total of 267 patients were analyzed; 83.5% were men, with a mean (SD) age at diagnosis of 68 (10.7) years. Incidental diagnosis was ascertained in 24.7% of cases. Asymptomatic patients presented more frequently stage I and II disease compared to symptomatic patients (51.5% vs. 14%), and exhibited a significantly better prognosis, with a 3-year OS of 63.6% (vs. 30.3%) and a median OS that was not reached during follow-up (vs. 10.3 months). With an adjusted multivariate Cox proportional hazard model, we obtained a HR (95% CI) of 2.63 (95% CI, 1.6-4.2; P<0.0001) associated with symptomatic presentation independently of age, sex, stage at diagnosis and ECOG scale. In addition, after performing the propensity score matching analysis, the Cox regression model continued to show a significantly worse prognosis for patients presenting with symptoms (P=0.041).

Conclusions: Lung cancer patients who are asymptomatic at diagnosis exhibit a significantly better prognosis, regardless of the stage of the disease, underlining the importance of an early diagnosis.

Keywords: Lung cancer; incidental diagnosis; prognosis.

Figure 1

Flowchart of the study recruitment.

Figure 2

Kaplan-Meier curve of the time between diagnosis and all-cause death between patients who were asymptomatic and symptomatic at diagnosis. OS, overall survival.

Figure 3

Hazard ratios (HR) and 95% confidence intervals (CI) for all-cause death. Multivariate Cox regression analysis adjusted by age, sex, disease stage, symptoms at diagnosis and ECOG scale. ECOG, Eastern Cooperative Oncology Group.