Lactobacillus supplementation for diarrhoea related to chemotherapy of colorectal cancer: a randomised study

Open-label, prospective, randomized, phase III, single-institution, 2×3 factorial design. 150 eligible colorectal cancer patients post-surgery (Dukes' B/C, n=126; Dukes' D metastatic, n=24); age 18–75 (median 60); 51% male; WHO performance status ≤2; adjuvant chemotherapy with Mayo regimen or simplified de Gramont; radiotherapy given for rectal cancer when indicated.

Lactobacillus rhamnosus GG: 1-2 × 10^10 CFU per day, orally in gelatin capsules, twice daily, during 24 weeks of adjuvant chemotherapy. Guar gum-containing nutritional supplement: 11 g guar gum per day (500 ml product) taken daily on cycle days 7–14 for 8 days per month, during 24 weeks of adjuvant chemotherapy.

Lactobacillus rhamnosus GG supplementation reduced grade 3–4 diarrhoea from 37% to 22% (P=0.027); also reduced abdominal discomfort, hospital care for bowel toxicity, and chemotherapy dose reductions due to bowel toxicity; no Lactobacillus-related toxicity detected. Guar gum fibre supplementation did not improve chemotherapy tolerability (severe diarrhoea: 25% with guar gum vs 30% without; P=0.24). The simplified de Gramont regimen was better tolerated than Mayo (45% vs 89% with any grade 3/4 adverse effects). Authors conclude daily Lactobacillus rhamnosus GG may reduce severe 5-FU–related diarrhoea and abdominal discomfort and is well tolerated; fibre supplementation may offer little benefit; Lactobacillus GG warrants further evaluation in this setting.

Open-label, non-blinded, single-institution trial; not placebo-controlled; 150 participants; older regimens not including irinotecan/capecitabine/oxaliplatin; diary-based adverse-event reporting may bias results; generalizability limited to similar regimens and settings.