Oral microbiota and cancer – what is the current state of knowledge?
DOI:
https://doi.org/10.12775/QS.2026.77.76054Keywords
cancer, microbiome, dysbiosis, oral microbiomeAbstract
Cancer is one of the leading causes of death worldwide, and increasing evidence suggests that bacteria and the human microbiome may contribute to its development. The oral microbiome is one of the most diverse microbial communities in the body and may influence both local and systemic diseases. This review summarizes current knowledge on the relationship between oral microbiome dysbiosis and cancer, focusing on possible mechanisms, risk factors, and diagnostic potential. A structured literature review was performed using major scientific databases, including studies published between 2000 and 2026. The available evidence shows that oral microbiome alterations are associated with several types of cancer, particularly oral, digestive tract, and hematological cancers. Further research is needed to clarify whether these changes contribute directly to cancer development and whether oral microbiome assessment could be useful for cancer prevention, screening, or treatment.
References
1. Santucci C, Mignozzi S, Levi F, et al. European cancer mortality predictions for the year 2025 with focus on breast cancer. Annals of Oncology. 2025;36(4):460-468. doi:10.1016/j.annonc.2025.01.014
2. Brennan P, Davey-Smith G. Identifying Novel Causes of Cancers to Enhance Cancer Prevention: New Strategies Are Needed. J Natl Cancer Inst. 2022;114(3):353-360. doi:10.1093/jnci/djab204
3. Zhang L, Liu Y, Zheng HJ, Zhang CP. The Oral Microbiota May Have Influence on Oral Cancer. Front Cell Infect Microbiol. 2020;9. doi:10.3389/fcimb.2019.00476
4. Wroblewski LE, Peek RM, Wilson KT. Helicobacter pylori and Gastric Cancer: Factors That Modulate Disease Risk. Clinical Microbiology Reviews. 2010;23(4):713-739. doi:10.1128/cmr.00011-10
5. Tuominen H, Rautava J. Oral Microbiota and Cancer Development. Pathobiology. 2020;88(2):116-126. doi:10.1159/000510979
6. Kamrani P, Sadiq NM. Anatomy, Head and Neck, Oral Cavity (Mouth). In: StatPearls. StatPearls Publishing; 2026. Accessed July 1, 2026. http://www.ncbi.nlm.nih.gov/books/NBK545271/
7. Santacroce L, Passarelli PC, Azzolino D, et al. Oral microbiota in human health and disease: A perspective. Exp Biol Med (Maywood). 2023;248(15):1288-1301. doi:10.1177/15353702231187645
8. The Human Oral Microbiome | Journal of Bacteriology. Accessed July 1, 2026. https://journals.asm.org/doi/full/10.1128/jb.00542-10
9. Caselli E, Fabbri C, D’Accolti M, et al. Defining the oral microbiome by whole-genome sequencing and resistome analysis: the complexity of the healthy picture. BMC Microbiol. 2020;20(1):120. doi:10.1186/s12866-020-01801-y
10. Osiak J, Wołowiec Ł, Żukow X, et al. Oral microbial dysbiosis in cardiovascular diseases. Journal of Education, Health and Sport. 2023;41(1):170-186.
11. Tuganbaev T, Yoshida K, Honda K. The effects of oral microbiota on health. Science. 2022;376(6596):934-936. doi:10.1126/science.abn1890
12. Coussens LM, Werb Z. Inflammation and cancer. Nature. 2002;420(6917):860-867. doi:10.1038/nature01322
13. Mantovani A, Allavena P, Sica A, Balkwill F. Cancer-related inflammation. Nature. 2008;454(7203):436-444. doi:10.1038/nature07205
14. Ng JH, Iyer NG, Tan MH, Edgren G. Changing epidemiology of oral squamous cell carcinoma of the tongue: A global study. Head & Neck. 2017;39(2):297-304. doi:10.1002/hed.24589
15. Rumgay H, Colombet M, Ramos da Cunha A, et al. Global incidence of lip, oral cavity, and pharyngeal cancers by subsite in 2022. CA: A Cancer Journal for Clinicians. 2026;76(1). doi:10.3322/caac.70048
16. Perera M, Al-Hebshi NN, Speicher DJ, Perera I, Johnson NW. Emerging role of bacteria in oral carcinogenesis: a review with special reference to perio-pathogenic bacteria. Journal of oral microbiology. 2016;8(1):32762.
17. Landskron G, De la Fuente M, Thuwajit P, Thuwajit C, Hermoso MA. Chronic Inflammation and Cytokines in the Tumor Microenvironment. Journal of Immunology Research. 2014;2014(1):149185. doi:10.1155/2014/149185
18. Patel A, Sant S. Hypoxic tumor microenvironment: Opportunities to develop targeted therapies. Biotechnology Advances. 2016;34(5):803-812. doi:10.1016/j.biotechadv.2016.04.005
19. Zhao H, Chu M, Huang Z, et al. Variations in oral microbiota associated with oral cancer. Sci Rep. 2017;7(1):11773. doi:10.1038/s41598-017-11779-9
20. Guthmiller JM, Novak KF. Periodontal Diseases. In: Polymicrobial Diseases. ASM Press; 2002. Accessed July 2, 2026. https://www.ncbi.nlm.nih.gov/books/NBK2496/
21. Pendyala G, Joshi S, Chaudhari S, Gandhage D. Links demystified: Periodontitis and cancer. Dent Res J (Isfahan). 2013;10(6):704-712.
22. Ray RR. Periodontitis: An Oral Disease with Severe Consequences. Appl Biochem Biotechnol. 2023;195(1):17-32. doi:10.1007/s12010-022-04127-9
23. Wu Y, Shi X, Li Y, et al. Hematopoietic and lymphatic cancers in patients with periodontitis: a systematic review and meta-analysis. Med Oral Patol Oral Cir Bucal. 2020;25(1):e21-e28. doi:10.4317/medoral.23166
24. Yao QW, Zhou DS, Peng HJ, Ji P, Liu DS. Association of periodontal disease with oral cancer: a meta-analysis. Tumor Biol. 2014;35(7):7073-7077. doi:10.1007/s13277-014-1951-8
25. Eliot MN, Michaud DS, Langevin SM, McClean MD, Kelsey KT. Periodontal disease and mouthwash use are risk factors for head and neck squamous cell carcinoma. Cancer Causes Control. 2013;24(7):1315-1322. doi:10.1007/s10552-013-0209-x
26. Freudenheim JL, Genco RJ, LaMonte MJ, et al. Periodontal disease and breast cancer: prospective cohort study of postmenopausal women. Cancer Epidemiology, Biomarkers & Prevention. 2016;25(1):43-50.
27. Michaud DS, Izard J, Wilhelm-Benartzi CS, et al. Plasma antibodies to oral bacteria and risk of pancreatic cancer in a large European prospective cohort study. Gut. 2013;62(12):1764-1770.
28. Lee WH, Chen HM, Yang SF, et al. Bacterial alterations in salivary microbiota and their association in oral cancer. Scientific reports. 2017;7(1):16540.
29. Mager D, Haffajee A, Devlin P, Norris C, Posner M, Goodson J. The salivary microbiota as a diagnostic indicator of oral cancer: a descriptive, non-randomized study of cancer-free and oral squamous cell carcinoma subjects. Journal of translational medicine. 2005;3(1):27.
30. Schmidt BL, Kuczynski J, Bhattacharya A, et al. Changes in abundance of oral microbiota associated with oral cancer. PloS one. 2014;9(6):e98741.
31. Zhou X, Hao Y, Peng X, et al. The Clinical Potential of Oral Microbiota as a Screening Tool for Oral Squamous Cell Carcinomas. Front Cell Infect Microbiol. 2021;11. doi:10.3389/fcimb.2021.728933
32. Zhang L, Liu Y, Zheng HJ, Zhang CP. The Oral Microbiota May Have Influence on Oral Cancer. Front Cell Infect Microbiol. 2020;9. doi:10.3389/fcimb.2019.00476
33. Sarkar P, Malik S, Laha S, et al. Dysbiosis of Oral Microbiota During Oral Squamous Cell Carcinoma Development. Front Oncol. 2021;11. doi:10.3389/fonc.2021.614448
34. Zhao H, Chu M, Huang Z, et al. Variations in oral microbiota associated with oral cancer. Scientific reports. 2017;7(1):11773.
35. Hsiao JR, Chang CC, Lee WT, et al. The interplay between oral microbiome, lifestyle factors and genetic polymorphisms in the risk of oral squamous cell carcinoma. Carcinogenesis. 2018;39(6):778-787.
36. Yang SF, Huang HD, Fan WL, et al. Compositional and functional variations of oral microbiota associated with the mutational changes in oral cancer. Oral Oncology. 2018;77:1-8. doi:10.1016/j.oraloncology.2017.12.005
37. Yang CY, Yeh YM, Yu HY, et al. Oral Microbiota Community Dynamics Associated With Oral Squamous Cell Carcinoma Staging. Front Microbiol. 2018;9. doi:10.3389/fmicb.2018.00862
38. Pushalkar S, Ji X, Li Y, et al. Comparison of oral microbiota in tumor and non-tumor tissues of patients with oral squamous cell carcinoma. BMC Microbiol. 2012;12(1):144. doi:10.1186/1471-2180-12-144
39. Sasaki M, Yamaura C, Ohara-Nemoto Y, et al. Streptococcus anginosus infection in oral cancer and its infection route. Oral Diseases. 2005;11(3):151-156. doi:10.1111/j.1601-0825.2005.01051.x
40. Amer A, Galvin S, Healy CM, Moran GP. The Microbiome of Potentially Malignant Oral Leukoplakia Exhibits Enrichment for Fusobacterium, Leptotrichia, Campylobacter, and Rothia Species. Front Microbiol. 2017;8. doi:10.3389/fmicb.2017.02391
41. Kageyama S, Takeshita T, Takeuchi K, et al. Characteristics of the Salivary Microbiota in Patients With Various Digestive Tract Cancers. Front Microbiol. 2019;10. doi:10.3389/fmicb.2019.01780
42. Li Y, Tan X, Zhao X, et al. Composition and function of oral microbiota between gingival squamous cell carcinoma and periodontitis. Oral Oncology. 2020;107:104710. doi:10.1016/j.oraloncology.2020.104710
43. Katz J, Onate MD, Pauley KM, Bhattacharyya I, Cha S. Presence of Porphyromonas gingivalis in gingival squamous cell carcinoma. Int J Oral Sci. 2011;3(4):209-215. doi:10.4248/IJOS11075
44. Wolf A, Moissl-Eichinger C, Perras A, Koskinen K, Tomazic PV, Thurnher D. The salivary microbiome as an indicator of carcinogenesis in patients with oropharyngeal squamous cell carcinoma: A pilot study. Sci Rep. 2017;7(1):5867. doi:10.1038/s41598-017-06361-2
45. Lim Y, Fukuma N, Totsika M, Kenny L, Morrison M, Punyadeera C. The Performance of an Oral Microbiome Biomarker Panel in Predicting Oral Cavity and Oropharyngeal Cancers. Front Cell Infect Microbiol. 2018;8. doi:10.3389/fcimb.2018.00267
46. Börnigen D, Ren B, Pickard R, et al. Alterations in oral bacterial communities are associated with risk factors for oral and oropharyngeal cancer. Sci Rep. 2017;7(1):17686. doi:10.1038/s41598-017-17795-z
47. Börnigen D, Ren B, Pickard R, et al. Alterations in oral bacterial communities are associated with risk factors for oral and oropharyngeal cancer. Sci Rep. 2017;7(1):17686. doi:10.1038/s41598-017-17795-z
48. Oliva M, Schneeberger PHH, Rey V, et al. Transitions in oral and gut microbiome of HPV+ oropharyngeal squamous cell carcinoma following definitive chemoradiotherapy (ROMA LA-OPSCC study). Br J Cancer. 2021;124(9):1543-1551. doi:10.1038/s41416-020-01253-1
49. Debelius JW, Huang T, Cai Y, et al. Subspecies Niche Specialization in the Oral Microbiome Is Associated with Nasopharyngeal Carcinoma Risk. mSystems. 2020;5(4):10.1128/msystems.00065-20. doi:10.1128/msystems.00065-20
50. Chen Z, Wong PY, Ng CWK, et al. The Intersection between Oral Microbiota, Host Gene Methylation and Patient Outcomes in Head and Neck Squamous Cell Carcinoma. Cancers. 2020;12(11):3425. doi:10.3390/cancers12113425
51. Hayes RB, Ahn J, Fan X, et al. Association of Oral Microbiome With Risk for Incident Head and Neck Squamous Cell Cancer. JAMA Oncol. 2018;4(3):358-365. doi:10.1001/jamaoncol.2017.4777
52. Guerrero-Preston R, Godoy-Vitorino F, Jedlicka A, et al. 16S rRNA amplicon sequencing identifies microbiota associated with oral cancer, human papilloma virus infection and surgical treatment. Oncotarget. 2016;7(32):51320-51334. doi:10.18632/oncotarget.9710
53. Shiga K, Tateda M, Saijo S, et al. Presence of Streptococcus infection in extra-oropharyngeal head and neck squamous cell carcinoma and its implication in carcinogenesis. Oncology reports. 2001;8(2):245-248.
54. Bhatt AP, Redinbo MR, Bultman SJ. The role of the microbiome in cancer development and therapy. CA: A Cancer Journal for Clinicians. 2017;67(4):326-344. doi:10.3322/caac.21398
55. Carbonero F, Benefiel AC, Alizadeh-Ghamsari AH, Gaskins HR. Microbial pathways in colonic sulfur metabolism and links with health and disease. Front Physiol. 2012;3. doi:10.3389/fphys.2012.00448
56. Kageyama S, Takeshita T, Takeuchi K, et al. Characteristics of the Salivary Microbiota in Patients With Various Digestive Tract Cancers. Front Microbiol. 2019;10. doi:10.3389/fmicb.2019.01780
57. Gao S, Li S, Ma Z, et al. Presence of Porphyromonas gingivalis in esophagus and its association with the clinicopathological characteristics and survival in patients with esophageal cancer. Infect Agents Cancer. 2016;11(1):3. doi:10.1186/s13027-016-0049-x
58. Chen X, Winckler B, Lu M, et al. Oral Microbiota and Risk for Esophageal Squamous Cell Carcinoma in a High-Risk Area of China. PLOS ONE. 2015;10(12):e0143603. doi:10.1371/journal.pone.0143603
59. Wang Q, Rao Y, Guo X, et al. Oral Microbiome in Patients with Oesophageal Squamous Cell Carcinoma. Sci Rep. 2019;9(1):19055. doi:10.1038/s41598-019-55667-w
60. Snider EJ, Compres G, Freedberg DE, et al. Barrett’s esophagus is associated with a distinct oral microbiome. Clinical and Translational Gastroenterology. 2018;9(3):e135. doi:10.1038/s41424-018-0005-8
61. Narikiyo M, Tanabe C, Yamada Y, et al. Frequent and preferential infection of Treponema denticola, Streptococcus mitis, and Streptococcus anginosus in esophageal cancers. Cancer Science. 2004;95(7):569-574. doi:10.1111/j.1349-7006.2004.tb02488.x
62. Zhao Q, Yang T, Yan Y, et al. Alterations of Oral Microbiota in Chinese Patients With Esophageal Cancer. Front Cell Infect Microbiol. 2020;10. doi:10.3389/fcimb.2020.541144
63. Farrell JJ, Zhang L, Zhou H, et al. Variations of oral microbiota are associated with pancreatic diseases including pancreatic cancer. Gut. 2012;61(4):582-588. doi:10.1136/gutjnl-2011-300784
64. Sun H, Zhao X, Zhou Y, et al. Characterization of Oral Microbiome and Exploration of Potential Biomarkers in Patients with Pancreatic Cancer. BioMed Research International. 2020;2020(1):4712498. doi:10.1155/2020/4712498
65. Fan X, Alekseyenko AV, Wu J, et al. Human oral microbiome and prospective risk for pancreatic cancer: a population-based nested case-control study. Gut. 2018;67(1):120-127. doi:10.1136/gutjnl-2016-312580
66. Vogtmann E, Han Y, Caporaso JG, et al. Oral microbial community composition is associated with pancreatic cancer: A case-control study in Iran. Cancer Medicine. 2020;9(2):797-806. doi:10.1002/cam4.2660
67. Torres PJ, Fletcher EM, Gibbons SM, Bouvet M, Doran KS, Kelley ST. Characterization of the salivary microbiome in patients with pancreatic cancer. PeerJ. 2015;3:e1373. doi:10.7717/peerj.1373
68. Olson SH, Satagopan J, Xu Y, et al. The oral microbiota in patients with pancreatic cancer, patients with IPMNs, and controls: a pilot study. Cancer Causes Control. 2017;28(9):959-969. doi:10.1007/s10552-017-0933-8
69. Lu H, Ren Z, Li A, et al. Tongue coating microbiome data distinguish patients with pancreatic head cancer from healthy controls. Journal of Oral Microbiology. 2019;11(1):1563409. doi:10.1080/20002297.2018.1563409
70. Gaiser RA, Halimi A, Alkharaan H, et al. Enrichment of oral microbiota in early cystic precursors to invasive pancreatic cancer. Published online December 1, 2019. doi:10.1136/gutjnl-2018-317458
71. Michaud DS, Izard J. Microbiota, Oral Microbiome, and Pancreatic Cancer. The Cancer Journal. 2014;20(3):203. doi:10.1097/PPO.0000000000000046
72. Wang Y, Zhang Y, Qian Y, et al. Alterations in the oral and gut microbiome of colorectal cancer patients and association with host clinical factors. International Journal of Cancer. 2021;149(4):925-935. doi:10.1002/ijc.33596
73. Zhang S, Kong C, Yang Y, et al. Human oral microbiome dysbiosis as a novel non-invasive biomarker in detection of colorectal cancer. Theranostics. 2020;10(25):11595-11606. doi:10.7150/thno.49515
74. Flemer B, Warren RD, Barrett MP, et al. The oral microbiota in colorectal cancer is distinctive and predictive. Gut. 2018;67(8):1454-1463. doi:10.1136/gutjnl-2017-314814
75. Ahn J, Sinha R, Pei Z, et al. Human Gut Microbiome and Risk for Colorectal Cancer. J Natl Cancer Inst. 2013;105(24):1907-1911. doi:10.1093/jnci/djt300
76. Uchino Y, Goto Y, Konishi Y, et al. Colorectal Cancer Patients Have Four Specific Bacterial Species in Oral and Gut Microbiota in Common—A Metagenomic Comparison with Healthy Subjects. Cancers. 2021;13(13):3332. doi:10.3390/cancers13133332
77. Kato I, Vasquez AA, Moyerbrailean G, et al. Oral microbiome and history of smoking and colorectal cancer. Journal of Epidemiological Research. 2016;2(2):92. doi:10.5430/jer.v2n2p92
78. Castellarin M, Warren RL, Freeman JD, et al. Fusobacterium nucleatum infection is prevalent in human colorectal carcinoma. Genome Research. 2012;22(2):299-306. doi:10.1101/gr.126516.111
79. Flanagan L, Schmid J, Ebert M, et al. Fusobacterium nucleatum associates with stages of colorectal neoplasia development, colorectal cancer and disease outcome. Eur J Clin Microbiol Infect Dis. 2014;33(8):1381-1390. doi:10.1007/s10096-014-2081-3
80. Tahara T, Yamamoto E, Suzuki H, et al. Fusobacterium in Colonic Flora and Molecular Features of Colorectal Carcinoma. Cancer Res. 2014;74(5):1311-1318. doi:10.1158/0008-5472.CAN-13-1865
81. Gao Z, Guo B, Gao R, Zhu Q, Qin H. Microbiota disbiosis is associated with colorectal cancer. Front Microbiol. 2015;6. doi:10.3389/fmicb.2015.00020
82. Wu J, Xu S, Xiang C, et al. Tongue Coating Microbiota Community and Risk Effect on Gastric Cancer. Journal of Cancer. 2018;9(21):4039-4048. doi:10.7150/jca.25280
83. Huang K, Gao X, Wu L, et al. Salivary Microbiota for Gastric Cancer Prediction: An Exploratory Study. Front Cell Infect Microbiol. 2021;11. doi:10.3389/fcimb.2021.640309
84. Hu J, Han S, Chen Y, Ji Z. Variations of Tongue Coating Microbiota in Patients with Gastric Cancer. BioMed Research International. 2015;2015(1):173729. doi:10.1155/2015/173729
85. Sun JH, Li XL, Yin J, Li YH, Hou BX, Zhang Z. A screening method for gastric cancer by oral microbiome detection. Oncology Reports. 2018;39(5):2217-2224. doi:10.3892/or.2018.6286
86. Lu H, Ren Z, Li A, et al. Deep sequencing reveals microbiota dysbiosis of tongue coat in patients with liver carcinoma. Sci Rep. 2016;6:33142. doi:10.1038/srep33142
87. Multhoff G, Molls M, Radons J. Chronic Inflammation in Cancer Development. Front Immunol. 2012;2. doi:10.3389/fimmu.2011.00098
88. Rajasekaran JJ, Krishnamurthy HK, Bosco J, et al. Oral Microbiome: A Review of Its Impact on Oral and Systemic Health. Microorganisms. 2024;12(9):1797. doi:10.3390/microorganisms12091797
89. Intan Suhana M, Farha A, Hassan B. Inflammation of the Gums. Malays Fam Physician. 2020;15(1):71-73.
90. Sedghi L, DiMassa V, Harrington A, Lynch SV, Kapila YL. The oral microbiome: Role of key organisms and complex networks in oral health and disease. Periodontology 2000. 2021;87(1):107-131. doi:10.1111/prd.12393
91. Zhang S, Kong C, Yang Y, et al. Human oral microbiome dysbiosis as a novel non-invasive biomarker in detection of colorectal cancer. Theranostics. 2020;10(25):11595-11606. doi:10.7150/thno.49515
92. Su SC, Chang LC, Huang HD, et al. Oral microbial dysbiosis and its performance in predicting oral cancer. Carcinogenesis. 2021;42(1):127-135. doi:10.1093/carcin/bgaa062
93. Chattopadhyay I, Verma M, Panda M. Role of Oral Microbiome Signatures in Diagnosis and Prognosis of Oral Cancer. Technol Cancer Res Treat. 2019;18:1533033819867354. doi:10.1177/1533033819867354
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