Mucosal microflora in head and neck cancer patients

Objective To analyse the tongue and buccal microflora prospectively in head and neck cancer patients treated with radiation therapy (RT). Methods In 33 dentate patients, microbial samples from the tongue and buccal mucosa were collected pretreatment, during treatment, and 6 months, 1 year and 2 years post‐treatment. Microorganisms associated with oral health and oral disorders were analysed using cultivation technique. Oral mucositis was scored at the appointment during treatment. Results Compared with pretreatment, lactobacilli and Candida increased on the tongue, while streptococci and Neisseria decreased during treatment. Two years post‐treatment, Neisseria and Prevotella were decreased and Candida increased. On the buccal mucosa, an increased growth of lactobacilli and increased detection frequencies of the opportunistic bacteria Staphylococcus aureus, Gram‐negative enteric rods and enterococci were seen during treatment compared with pretreatment. Seventy per cent showed severe mucositis during treatment. Two years post‐treatment the total count as well as streptococci, Neisseria and Fusobacterium nucleatum were decreased and lactobacilli increased compared with pretreatment. Conclusion Despite improvements in treatment for cancer in the head and neck region, microorganisms associated with oral health decrease during treatment and mucosal pathogens increase. Two years post‐treatment, levels of acid‐tolerant (lactobacilli and Candida) were increased, while acid‐sensitive microorganisms (Neisseria and F. nucleatum) were decreased, plausibly due to persisting decreased salivary secretion rate.