Demers, M., Dagnault, A., & Desjardins, J. (2013). A randomized double-blind controlled trial: Impact of probiotics on diarrhea in patients treated with pelvic radiation. Clinical Nutrition (Edinburgh, Scotland), 33(5), 761–767. 

To determine the effectiveness of the probiotic Bifilact^® (Lactobacillus acidophilus LAC-361) on moderate and severe treatment-induced diarrhea in patients with pelvic cancer undergoing therapy, with a secondary objective to assess whether Bifilact^® decreased or delayed the need for antidiarrheal medication, reduced intestinal pain, decreased hospitalization, lowered the interruption of radiotherapy treatments or doses of both radiotherapy and chemotherapy, and improved the overall well-being of patients during treatment

Patients were divided into three groups: prostatic cancers, gynecologic cancers without chemotherapy, and gynecologic or rectal cancers with chemotherapy. Then, using double-blind procedures, patients were block-randomized by blocks of two, four, or six patients according to random permutations. A second random block using a higher probiotic dosage was added after an interim analysis. New, random lists were generated for each stratum with a 3:1:1 ratio (higher dose, standard dose, placebo). Nutritional intervention was enacted with a diet teaching to control dietary lipids and providing recommendations on fiber and carbohydrate intake. Yogurt consumption was encouraged.

• N = 246  
• MEAN AGE = Placebo 60.6 years; standard-dose 61.4 years; high-dose 62.0 years
• MALES: Placebo 63; standard-dose 72; high-dose 66, FEMALES: Placebo 37; standard-dose 28; high-dose 34
• KEY DISEASE CHARACTERISTICS: Prostate, endometrium, cervix, and rectum
• OTHER KEY SAMPLE CHARACTERISTICS: Surgery placebo 35%; standard-dose 39%; high-dose 30%; chemotherapy placebo 56%; standard-dose 54%; high-dose 45%

• SITE: Single-site    
• SETTING TYPE: Outpatient    
• LOCATION: L’Hôtel-Dieu de Québec University Health Center, Canada

• PHASE OF CARE: Active antitumor treatment

Prospective, single-center, placebo-controlled, randomized, double-blinded trial

• World Health Organization (WHO) scale of abdominal pain
• National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI, CTCAE) version 3.0 
• Fecal incontinence NCI scale version 3.0 stool consistency
• An adapted Bristol Stool Scale (BSS) was used to facilitate use by patients: grade 1 = normal stools (BSS 1–4); grade 2 = soft stools, in pieces (BSS 5–6), and grade 3 = liquid stools, no shape (BSS 7). 
• Patients undergoing chemotherapy received a weekly complete blood count. If a patient's neutrophil count was ≤ 1.5 x 10⁹/L, study agent was discontinued.
• A log book was kept for symptom documentation, stools, and medications such as antidiarrheals. 
• The European Organization for the Research and Treatment of Cancer's Quality of Life Questionairre C30 (EORTC, QLQ-C30) was completed at baseline, after radiation therapy was completed, and two weeks later.

229 patients were analyzed. For the primary endpoint among all groups, there was no difference in the effectiveness of the probiotic Bifilact^® (Lactobacillus acidophilus LAC-361) on moderate and severe treatment-induced diarrhea. At the 60-day point, there were more patients without moderate and severe diarrhea in the standard-dose group (35%) compared with the placebo group (17%) (hazard ratio of 0.69, p = 0.04). The postsurgical group with patients taking the standard dose had fewer patients without very severe diarrhea compared to the placebo group (97% and 74%, respectively) (p = 0.03). While undergoing therapy, the average number of bowel movements per day during treatment was less than three soft stools (p = 0.80), and the median level of abdominal pain was < 1 based on the NCI scale (p = 0.23).

Bifilact^®, when administered in standard doses to patients with pelvic cancer undergoing therapy, may reduce the risk of radiation-induced grades 2–4 diarrhea towards the end of the treatment. While receiving radiation therapy, a standard dose of probiotics may reduce radiation-induced grade 4 diarrhea in patients who had prior surgery.

• Key sample group differences that could influence results

Nurses may want to consider offering counseling and education regarding probiotics as a potential alternative approach to reducing radiation-induced diarrhea.