Patterns of multiple primaries in fortyfour cancer patients: a single-center clinical experience

Introduction. Multiple primaries are defined as the existence of more than one synchronous or metachronous cancer type in the same individual. Due to a longer follow-up time after a primary cancer diagnosis, the likelihood of detection of a second primary is also increased. We report on patterns of multiple primaries in a cohort of cancer patients from a single institution.Material and methods. We identified 44 patients with multiple primaries that were diagnosed, treated, and followed up between March 2011 and January 2022 from our prospectively maintained database at the Hatay Education and Research Hospital Cancer Unit.Results. The median follow-up time was 60 months (range; 3-103). The median time between the diagnosis of the first primary and the second primary was 29 months (range; 0-94). The median OS was 76 months (95% Cl 26.6-125.4) from the first diagnosis and 27 months (95% Cl 0.65-53.4) from the diagnosis of the second primary for the entire cohort. The first diagnosed tumor was localized in the gastrointestinal system in 43.2% of patients and 65.9% of all tumors were adenocarcinoma. The first diagnosed cancer was at an early stage (Stages I and II) in 63.6% of patients. At the staging evaluation of the second primary, 54.5% of patients were found to be in the early stage (Stages I and II) and 45.5% were found to be in the late stage (Stages III and IV).Conclusions. Our study is important as this is the largest cohort study about practical implications of managing multiple primaries. The risk of second and further primaries should be kept in mind in the active follow-up Introduction and surveillance of cancer patients .