Risk factors for fast-growing lung cancers detected on chest CT: a retrospective cohort study.

Background: Chest CT follow-up is frequently used before a lung cancer is diagnosed. The current study aims to explore the risk factors for the fast-growing lung cancers through a retrospective cohort study. Methods: This study selected eligible participants from a cohort of 39799 patients pathologically diagnosed with primary lung cancer at West China Hospital of Sichuan University from 2009 to 2020. Ultimately, 1693 patients were included, who were followed up with at least two chest CT images available before diagnosis. The volume/mass doubling time (VDT/MDT) of all lung cancers were calculated, and a fast-growing lung cancer was defined if the VDT/MDT was less than 400 days. Multivariate logistic regression analysis was used to explore risk factors associated with fast-growing lung cancers in the overall population, as well as in the solid and subsolid subgroups. Results: Among the 1693 patients (median age 56 years, 37% male, 21% ever smokers, 27% with solid density), 302 (18%) were classified as having fast-growing lung cancer. In the subgroup analysis of solid versus subsolid groups, fast-growing lung cancer accounted for 41% and 9.4%, respectively. In the overall population, risk factors independently associated with rapid growth included solid density, male sex, smoking history, personal and family history of malignancy. In the solid subgroup, the risk factors were male sex and smoking history, while in the subsolid subgroup, only smoking history was significant. Additionally, analysis of 128 patients with a 56-gene panel (18% with rapid growth) identified TP53 as an independent risk factor for fast growth. Conclusions: This study found risk factors associated with fast-growing lung cancers, helping to identify patients at high risk of disease progression.