Abstract 102P
Background
With the increasing use of the computed tomography (CT) scans, the clinicians more commonly encounter incidentally detected pulmonary nodules, parts of which are finally diagnosed as primary lung cancer during follow-up. The clinical characteristics of incidentally detected lung cancers (IDLCs) have not been well known in South Korea. In this study, we compared the clinical characteristics and prognosis of IDLC and screening detected lung cancer (SDLC).
Methods
This retrospective study included the subjects with pulmonary nodules (<3cm) at the baseline CT scans, which were pathologically confirmed as primary lung cancer in year 2015. The study population was classified as IDLC and SDLC according to the setting of the first pulmonary nodule detection. The symptomatic subjects at the time of the pulmonary nodule detection were excluded. Clinicoradiologic characteristics and overall survival (OS) rates were compared between the IDLC and SDLC groups.
Results
Among 553 study subjects, 209 (37.8%) IDLCs and 344 (62.2%) SDLCs were identified. IDLCs were most commonly discovered by the surveillance of other malignancy (36.4%) followed by the evaluation of benign diseases (32.1%). The IDLC group was older and had more smokers compared with the SDLC group. Adenocarcinomas were more commonly detected in the SDLC group (84.6%) than in the ILDC group (78.0%, P<0.001). The rates of pulmonary resection in the IDLC and SDLC groups were 86.1% and 87.8%, respectively (P=0.662). The 5-year OS rates of the IDLC group (80.9%) was similar to that of the SDLC group (84.9%, P=0.150).
Conclusions
Among non-symptomatic lung cancer patients, the proportion of IDLC was about 38% in our cohort. The IDLC group was associated with old age, smokers, history of other malignancy, and non-adenocarcinoma histology. However, the prognosis of the IDLC group was not inferior to the SDLC group.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.