A combination of probiotics significantly enhanced immune responses and reduced the severity of oral mucositis among patients with nasopharyngeal carcinoma who were undergoing concurrent chemoradiotherapy, according to results of a randomized, double-blind, placebo-controlled trial published in Cancer.
“For the first time, this study indicated that the probiotic combination had significantly enhanced the immunity of patients, reduced oral mucositis, and was beneficial for restoring microbial diversity after the end of concurrent chemoradiotherapy,” Chunling Jiang, MD, PhD, of Jiangxi Provincial Cancer Hospital in China, and colleagues wrote. “Therefore, this ... trial shows the benefits of oral probiotics for preventing oral mucositis.”
The mean incidence of oral mucositis in patients with head or neck cancer undergoing concurrent chemoradiotherapy or altered fractionation radiotherapy is about 80%, causing interruptions in therapy at a frequency of up to 19% and adding substantially to the costs of care.
To date, there are no effective ways to overcome oral mucositis.
Researchers randomly assigned 99 patients with locally advanced nasopharyngeal carcinoma who were undergoing concurrent chemoradiotherapy to a regimen of probiotics (n = 64) or a placebo (n = 35).
The probiotic combination contained Bifidobacterium longum, Lactobacillus lactis and Enterococcus faecium.
Researchers excluded six patients from the probiotic group for failing to undergo follow-up, at the patient’s request or because of poor drug compliance..
Participants took the probiotic combination or placebo twice a day for up to 7 weeks.
Grade 3 or higher oral mucositis served as the primary endpoint. Secondary endpoints included short-term curative effect, the immune index and fecal flora changes.
Results showed that patients taking probiotics had a significant reduction in the severity of oral mucositis.
The incidence rates of oral mucositis were:
- Grade 0: 0 patients in probiotics group vs. 7 patients (12%) in placebo group;
- Grade 1: 0 vs. 32 (55.1%);
- Grade 2: 19 (54.2%) vs. 10 (17.2%); and
- Grade 3: 16 (45.7%) vs. 9 (15.5%)
The probiotic combination increased the number of CD4-positive T cells (76.5% vs. 52.8%), CD8-positive T cells (62.9% vs. 29.7%) and CD3-positive T cells (69.7% vs. 45.4%), and it restored microbial diversity after chemoradiotherapy to that of healthy people.
The probiotic regimen did not affect tumor response to concurrent chemoradiotherapy. All patients reached parallel objective response rates.
Researchers suggested future studies include a larger group of patients and continue to analyze the effect of probiotics to find the optimal doses.
“T cells play a central role in cell-mediated immunity,” Jiang and colleagues wrote. “The significance of enhanced numbers of CD3-positive T cells, CD8-positive T cells, and CD4-positive T cells in the [probiotic] group indicated that the probiotics confirmed their roles in modulating human immune responses to pathogens and tumor cells and were important in orchestrating overall immune responses.” – by John DeRosier
Disclosures: The National Natural Science Foundation of China funded this study. Jiang reports no relevant financial disclosures. Please see the study for all other authors’ relevant disclosures.