Periodontitis as a field of cancerization: association with carcinoembryonic antigen in colorectal cancer patients Mesa López, María José Bravo Pérez, Manuel Egea, Juan El-Amrani, Sara Bonilla, Marco Alberca, Fernando Mesa Aguado, Francisco Luis Colorectal neoplasms Periodontitis Carcinoembryonic antigen Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s00784-025-06399-x Objectives This study aimed to, first, determine the prevalence of periodontitis in patients diagnosed with colorectal cancer (CRC) through a comprehensive clinical periodontal evaluation, and second, to analyze the relationship between periodontitis and different tumor severity variables. Materials and methods In a cross-sectional and analytical study in patients with CRC, we divided the patients into two groups, periodontitis and non-periodontitis, based on a complete periodontal assessment (clinical attachment loss, probing pocket depth, bleeding on probing, plaque index, number of present teeth, and a periodontal severity index). In both groups, in addition to sociodemographic variables, 12 histopathological tumor severity variables were compared. Results Out of 59 patients diagnosed with CRC, 41 (69.5%, 95% CI: 56.1–80.8) were diagnosed with periodontitis. The mean values in ng/mL of baseline and peak carcinoembryonic antigen (CEA) in the periodontitis patient group, mean ± SD (0.44 ± 0.39, 0.69 ± 0.49), were much higher compared to the non-periodontitis group (0.11 ± 0.29, 0.35 ± 0.45), 95% CI: 0.12–0.54, p < 0.001 and 95% CI: 0.06–0.62, p = 0.005, respectively. The rest of the comparisons between the different characteristics and histopathological variables of the tumor showed very similar results between both groups. Conclusions The 69.5% prevalence of periodontitis in patients with colorectal cancer highlights the relationship between both diseases. Furthermore, the association between periodontitis and elevated CEA levels suggests a possible role of chronic inflammation in tumor susceptibility. However, the absence of an association with other histopathological variables suggests that periodontitis is not related to cancer severity. Clinical relevance Recognizing periodontitis as a potential field cancerization highlights the importance of periodontal management as a possible strategy to reduce CRC susceptibility. 2025-06-10T07:19:33Z 2025-06-10T07:19:33Z 2025-06-02 journal article Mesa-López, M.J., Bravo, M., Egea, J. et al. Periodontitis as a field of cancerization: association with carcinoembryonic antigen in colorectal cancer patients. Clin Oral Invest 29, 323 (2025). [https://doi.org/10.1007/s00784-025-06399-x] https://hdl.handle.net/10481/104550 10.1007/s00784-025-06399-x eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Springer Nature