Phase II Randomized, Double Blind Study of Probiotics in Patients With Cervical Cancer in Clinical Stages IIB Undergoing Concurrent Chemotherapy and Radiation Therapy

Globally, many cancer survivors have undergone radiotherapy (RT) to pelvic tumors, this confers an increased risk of intestinal damage, affecting the quality of life of patients. The role of intestinal microbiota on the development of gastrointestinal toxicity and radiation enteritis has been described in cervical cancer patients that received pelvic RT. In this project we investigated the effect that a fermented dairy beverage (Yakult) may have in the modulation of inflammation and consequently of gastrointestinal toxicity in locally advanced cervical cancer (LACC) patients treated with concomitant chemo-radiotherapy (CRT).

In Mexico, the incidence of cervical cancer is 23 cases in 100,000 women (2015, Secretaría de Salud). In the Mexican National Cancer Institute (Instituto Nacional de Cancerología; INCan), 80% of patients arrive at locally advanced stages (IB2-IVA), the standard treatment is based on CRT. Gastrointestinal symptoms experienced by patients that receive pelvic RT define the pelvic radiation disease (PRD). Acute PRD is the result of cell death in the crypt epithelium and an acute inflammatory response in the lamina propria, which results in an insufficient replacement of the villi, rupture and inflammation of the mucosal barrier. Symptoms develop in 60-80% of patients. These include nausea, diarrhea, tenesmus, abdominal pain, urgency, anorexia, bleeding and fatigue; these are dose-limiting symptoms and affect the patients' quality of life.

A recent study analyzed the microbiota of LACC patients and found that patients that develop PRD during treatment with CRT possess a different microbiota to those patients that do not develop severe gastrointestinal toxicity. Evidence points to the critical role that the microbiota and intestinal inflammation play for the development of PRD in LACC patients. Therefore, an optimal intervention that modulates the microbiota is essential. We aimed to investigate the effect that a dairy beverage fermented with the probiotic Lactobacillus casei Shirota may have on intestinal and systemic inflammation, and consequently gastrointestinal symptoms and quality of life in women with LACC, undergoing CRT.

METHODS. This study was a double blind, placebo-controlled trial for Stage IIB cervical cancer patients that underwent CRT. The intervention group consumed of 3 servings of the fermented dairy beverage (Yakult) a day. The control group consumed 3 servings of the placebo beverage (with the same organoleptic qualities of Yakult). Clinical toxicity was analyzed with the Common Toxicity Criteria Version 2. Quality of Life score was measured with the QLQC 30 EORTC questionnaire. Fecal calprotectin was quantified to determine intestinal inflammation. Pro- and anti-inflammatory cytokines were quantified in blood samples to determine systemic inflammation.