The oral microenvironment in patients with oral squamous cell carcinoma

Objectives: To describe the microbial environment of the oral cavity in patients with and without oral squamous cell carcinoma.

Methods: Study design is case-control with enrollment over 14 months at one treatment hospital. Case definition is adults aged 21-89 years presenting for surgical treatment for oral squamous cell carcinoma in situ to malignant and ICD 10 codes C00.3 – C14.8. Clinical exclusion criteria include previous cancer diagnosis (except skin cancers), previous treatment for current carcinoma, immune disorders, and glucococorticoid treatment. Control patients are adults aged 21-89 years presenting for surgical treatment for obstructive sleep apnea. Demographic and behavioral data were collected by interview. Unstimulated saliva was collected for detection of 40 periodontal pathogens using the “Checkerboard” DNA-DNA hybridization, and for detection of Chlamydia trachomatis by Gen-Probe APTIMA® Combo 2 test. Mucosa and saliva specimens were collected from lateral border of tongue by Denbur Multi-Brush and stored in 50% glycerol at -80ºC for detection of Candida species, and from the tonsillar fossa by Cytobrush® Plus GT Scored (Medscand® Medical) and transferred into 5 ml ThinPrep® PreservCyt solution for detection of HPV by using a modified Puregene (Qiagen) protocol for buccal cells.

Results: Overall response rate was 43% (46/107): cases at 51% (19/37) and controls at 39% (27/70). Cases (n=19) were white males (14/19) with mean age of 59 years and controls (n=27) were 56% male, 63% white, with mean age 47 years. Preliminary analysis shows no difference between groups for presence of Capnocytophaga gingivalis, and all were negative for Chlamydia trachomatis. Carriage frequency of Candida species was higher for cases and C.albicans was the most prevalent yeast species. HPV16 was detected in 3/16 cases.

Conclusion: Additional analyses will describe the selected microenvironment (bacterial, fungal, and viral) of the oral cavity in patients with and without oral squamous cell carcinoma.

Support in part from CDC/H75/CCH424532, NIDCR/NIH/T32DE017551, GCRC/RR01070