Time to treatment initiation of lung cancer and contributing factors from 2015-2020 utilizing Surveillance, Epidemiology and End Results program database.
Authors: Mariela Di Vanna, Saria Qaiser, Shreya Shambhavi, Sheilabi Seeburun, YUSRA B. MEDIK, Jose Iglesias
Journal: Journal of Clinical Oncology (2024)

1540 Background: Time from diagnosis of cancer to definitive therapy, or time to treatment initiation (TTI), has significant impact on prognosis. Kohorana et al performed an observational study in 2019 that found that TTI has increased in the United States with an absolute increased risk of mortality ranging from 1.2-3.2% per week in early-stage breast, lung, renal and pancreatic cancers. This study aims at identifying contributing factors and trends that can assist in shortening TTI of lung cancer. Methods: This is a retrospective cohort study conducted by review of Surveillance, Epidemiology and End Results Program database. Participants included 212,607 adults ages 18 and older diagnosed with lung cancer during 2015-2020. Variables contributing to TTI were studied like age, sex, race, marital status, geographic location, household income, stage and grade. TTI was measured as less than 30 days and greater than 30 days. ANOVA analysis was performed with SPSS and BlueSky Statistics, with p-value of &lt;0.05 as significant. Results: TTI was 1.30 months in males and 1.31 months in females (p=0.038). In patients less than 65 years, TTI was 1.14 months, while those greater than 65 had a delay of 1.38 months (p&lt;0.001). White patients had TTI of 1.26 months versus non-white patients, 1.44 months (p&lt;0.001). Married patients had TTI of 1.24 months versus 1.44 months in widowed patients (P&lt;0.001). Income less than $35,000 had less TTI (1.22 months) than income greater than $75,000 (1.33 months) (p&lt;0.001), but the population earning &lt;$35,000 was smaller (n=3,082) compared to &gt;$75,000 (n=209,525), therefore not representative of the total population. Metropolitan had longer TTI than nonmetropolitan at 1.34 months versus 1.24 months, p&lt;0.001. Grade IV had shorter TTI at 0.94 months with grades I and II having TTI of 1.42 and 1.46 months, respectively (p&lt;0.001). Localized cancers had the longest TTI at 1.71 months versus distant at 1.01 months (p&lt;0.001). More aggressive cancers had shorter TTI such as grade IV + distant at 0.76 months versus grade I + localized at 1.42 months. Association between grade and stage and impact on TTI was significant at p&lt;0.001. Conclusions: This study revealed significant factors influencing the duration from cancer diagnosis to treatment among adult patients greater than 18 years old diagnosed with lung cancers. Shorter TTI intervals were observed for females, younger individuals (&lt;65 years-old), white patients, married and those with higher tumor grades and distant cancer. Addressing these disparities requires targeted interventions that consider socioeconomic status, geographic location and cancer characteristics to ensure equitable access to timely and high-quality cancer care. Further investigation is warranted to fully understand the impact of factors such as household income and regional variations on treatment delays.