When patients undergo surgery for colorectal cancer (CRC), can probiotics help recover bowel functions, or even prevent postoperative infections and complications?
A new randomized, controlled trial by Yang, et al. from Shanghai, China, set out to investigate the effects of perioperative probiotic treatment (Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis) in patients who required surgery for CRC. The researchers assigned 60 patients with CRC to receive either a probiotic or a placebo for 12 days surrounding the surgery. In the probiotic group, researchers saw a reduction in the number of days to first flatus and to first defecation; furthermore, the incidence of diarrhea was lower in probiotic group. They observed no significant differences in the rates of infectious and non-infectious complications. The researchers concluded that probiotics may have a positive effect on recovery of bowel function in patients undergoing CRC surgery.
A study from 2013, however, did find that a slightly different mixture of probiotic strains prevented infectious complications after CRC surgery. In a double-blind, randomized clinical trial, Liu, et al. investigated the use of a probiotic mixture (Lactobacillus plantarum, Lactobacillus acidophilus-11, and Bifidobacterium longum-88) for preventing infections after colectomy. The researchers were also interested in knowing whether the possible protective effects of probiotics were associated with reduced intestinal permeability. Thus, they asked whether serum concentrations of zonulin, a protein that is a possible biomarker of intestinal permeability, would be lower in the group that received probiotics.
In the study, 150 individuals from Shanghai and Guangzhou, China received the probiotic or the placebo treatment orally for six days before the surgery and ten days after the surgery. The researchers found that the probiotic group experienced lower rates of infections and infectious complications, shorter duration of postoperative fever, and less antibiotic therapy than the control group. Thus, they concluded that perioperative probiotic intervention with the three tested strains may provide important benefits for colectomy patients.
Probiotic intervention was also associated with reduced zonulin concentrations in this study, possibly indicating lower intestinal permeability. From this, the authors hypothesized that the probiotics may have worked to protect patients’ intestinal barrier function. So far, however, it is impossible to tie the changes in intestinal permeability directly to the effects of the probiotics. Much more mechanistic research is necessary to find out how probiotics may lead to the observed positive effects in colectomy patients.
These two Chinese studies, taken together, show that probiotics may provide specific benefits for individuals undergoing surgery for CRC—faster recovery of bowel function and lower rates of infections and complications. Replication in different cohorts of patients is necessary before widespread clinical use should be considered.
Liu ZH, et al. (2013) The effects of perioperative probiotic treatment on serum zonulin concentration and subsequent postoperative infectious complications after colorectal cancer surgery: a double-center and double-blind randomized clinical trial. Am J Clin Nutr, 97:117–26 doi:10.3945/ajcn.112.053777
Yang Y, et al. (2016) The effect of perioperative probiotics treatment for colorectal cancer: short-term outcomes of a randomized controlled trial. Oncotarget doi: 10.18632/oncotarget.7045