PROJECT SUMMARY: This application is being submitted in response to the Notice of Special Interest (NOSI): NOT-CA-21-058. In Lao People's Democratic Republic (Lao PDR), tobacco smoking prevalence among cancer patients is high: 60% in men and 15% in women. Evidence from developed countries suggests that smoking cessation offers considerable benefits for cancer survivors, including improving cancer treatment outcomes, reducing recurrence rates, reducing second primary tumor development, and reducing overall cancer mortality rates. Despite, no tobacco treatment programs are available in major (public) hospitals in Lao PDR, including in cancer hospitals/institutions. The parent project (1R21CA253600-01, R21 phase: 9/1/2020–8/31/2022, R33 phase: 9/1/2022–8/31/2025) aims to adapt and evaluate the efficacy of our theoretically and empirically based mobile health (mHealth) technology to help Lao general patients quit smoking cigarettes. This mHealth automated treatment (AT) approach includes a fully automated, interactive, personalized, smartphone-based intervention for behavioral treatment, delivered through our Insight platform. In year 1 of the parent project, we have been adapting our intervention content to the sociocultural context, language, and communication styles of Laotians. The purpose of this application is to expand our mHealth- based AT to address the pressing need for smoking cessation among cancer survivors and their caregivers in Lao PDR. In this project, we will conduct 4 focus group discussion to ensure that our revised materials are comprehensible and relevant to these target populations. Next, we will conduct a pilot randomized controlled trial (RCT, N=80) to evaluate the preliminary efficacy of the intervention. Cancer survivors (n=40) and caregivers (n=40) of both sexes who smoke will be recruited at Setthathirath Hospital and Lao National Cancer Center. Similar to the parent project’s design, participants will be randomized to 1 of 2 treatment groups: standard care (SC) or AT (20 cancer survivors and 20 caregivers in each group). SC consists of brief advice to quit smoking, self-help written materials, and a 2-week supply of NRT (transdermal patches). AT consists of all SC components plus our fully-automated interactive smartphone-based treatment program, personalized and tailored to cancer survivors or caregivers. The primary RCT outcome is biochemically confirmed self-reported 7-day point prevalence abstinence at 3 months post-study enrollment. After the RCT, we will conduct in-depth interviews (IDIs) with a diverse sample of 20 cancer survivors and 20 caregivers in the RCT to explore why and how they could or could not stay abstinent. The specific aims are: 1) to evaluate the feasibility of AT in cancer survivors and caregivers, 2) to evaluate the preliminary efficacy of AT in each cancer survivor/caregiver subgroup, and 3) to use mixed methods linked data (i.e., RCT and IDIs) and joint displays to explore why participants did...