Probiotics Evaluation in Oncological Surgery: A Systematic Review of 36 Randomized Controlled Trials Assessing 21 Diverse Formulations

Survival and cancer recurrence after short-course perioperative probiotics in a randomized trial

BACKGROUND & AIMS

The long-term impact of perioperative probiotics remains understudied while mounting evidence links microbiome and oncogenesis. Therefore, we analyzed overall survival and cancer recurrence among patients enrolled in a randomized trial of perioperative probiotics.

METHODS

6-year follow-up of surgical patients participating in a randomized trial evaluating short-course perioperative oral probiotic VSL#3 (n = 57) or placebo (n = 63).

RESULTS

Study groups did not differ in age, preoperative hemoglobin, ASA status, and Charlson comorbidity index. There was a significant difference in preoperative serum albumin (placebo group 4.0 ± 0.1 vs. 3.7 ± 0.1 g/dL in the probiotic group, p = 0.030). Thirty-seven deaths (30.8 %) have occurred during a median follow-up of 6.2 years. Overall survival stratified on preoperative serum albumin and surgical specialty was similar between groups (p = 0.691). Age (aHR = 1.081, p = 0.001), serum albumin (aHR = 0.162, p = 0.001), and surgical specialty (aHR = 0.304, p < 0.001) were the only predictors of overall survival in the multivariate model, while the placebo/probiotic group (aHR = 0.808, p = 0.726) was not predictive. The progression rate among cancer patients was similar in the probiotic group (30.3 %, 10/33) compared to the placebo group (21.2 %, 7/33; p = 0.398). The progression-free survival was not significantly different (unstratified p = 0.270, stratified p = 0.317).

CONCLUSIONS

Perioperative short-course use of VSL#3 probiotics does not influence overall or progression-free survival after complex surgery for visceral malignancy.

Recommendations to Improve Quality of Probiotic Systematic Reviews With Meta-Analyses

Importance

Systematic reviews and meta-analyses often report conflicting results when assessing evidence for probiotic efficacy, partially because of the lack of understanding of the unique features of probiotic trials. As a consequence, clinical decisions on the use of probiotics have been confusing.

Objective

To provide recommendations to improve the quality and consistency of systematic reviews with meta-analyses on probiotics, so evidence-based clinical decisions can be made with more clarity.

Evidence Review

For this consensus statement, an updated literature review was conducted (January 1, 2020, to June 30, 2022) to supplement a previously published 2018 literature search to identify areas where probiotic systematic reviews with meta-analyses might be improved. An expert panel of 21 scientists and physicians with experience on writing and reviewing probiotic reviews and meta-analyses was convened and used a modified Delphi method to develop recommendations for future probiotic reviews.

Findings

A total of 206 systematic reviews with meta-analysis components on probiotics were screened and representative examples discussed to determine areas for improvement. The expert panel initially identified 36 items that were inconsistently reported or were considered important to consider in probiotic meta-analyses. Of these, a consensus was reached for 9 recommendations to improve the quality of future probiotic meta-analyses.

Conclusions and Relevance

In this study, the expert panel reached a consensus on 9 recommendations that should promote improved reporting of probiotic systematic reviews with meta-analyses and, thereby, assist in clinical decisions regarding the use of probiotics.

Synergistic Strategies for Gastrointestinal Cancer Care: Unveiling the Benefits of Immunonutrition and Microbiota Modulation

Gastrointestinal (GI) cancers are a group of highly prevalent malignant tumors affecting the gastrointestinal tract. Globally, one in four cancer cases and one in three cancer deaths are estimated to be GI cancers. They can alter digestive and absorption functions, leading to severe malnutrition which may worsen the prognosis of the patients. Therefore, nutritional intervention and monitoring play a fundamental role in managing metabolic alterations and cancer symptoms, as well as minimizing side effects and increasing the effectiveness of chemotherapy. In this scenario, the use of immunonutrients that are able to modulate the immune system and the modification/regulation of the gut microbiota composition have gained attention as a possible strategy to improve the conditions of these patients. The complex interaction between nutrients and microbiota might contribute to maintaining the homeostasis of each individual's immune system; therefore, concurrent use of specific nutrients in combination with traditional cancer treatments may synergistically improve the overall care of GI cancer patients. This work aims to review and discuss the role of immunonutrition and microbiota modulation in improving nutritional status, postoperative recovery, and response to therapies in patients with GI cancer.

Mistletoe Extracts during the Oncological Perioperative Period: A Systematic Review and Meta-Analysis of Human Randomized Controlled Trials

BACKGROUND

We aim to evaluate the safety and efficacy of mistletoe extract (ME) use during the oncological perioperative period.

METHODS

Details registered a priori on PROSPERO (CRD42018086168).

RESULTS

Seven RCTs (comprising 663 participants in nine reports) and three nonrandomized studies were included. In five RCTs, ME was evaluated as adjunctive care and the control group had no additional intervention, whereas in two RCTs, ME was compared head-to-head against common cancer treatments (i.e., etoposide or bacillus Calmette-Guérin) with the intervention groups not receiving standard care. Meta-analyses found no evidence for a difference between ME and no added therapy for mortality and recurrence (RR, 95% CI: 1.00, 0.79-1.27; and 1.03, 0.79-1.33, respectively). Two RCTs reported beneficial effects of ME on immune cells, specifically natural killer cells, in colorectal cancer, and one RCT reported quality of life improvement. Two RCTs reported ME discontinuations due to adverse events and grade 3/4 toxicities. Nevertheless, no safety signals were detected from these 10 studies. Quality appraisal revealed a substantial risk of bias.

CONCLUSIONS

Preliminary data are encouraging for mistletoe extracts, particularly in the context of colorectal cancer. However, the evidence is limited by the number of studies, an evaluation of different outcomes, and methodological limitations. Further high-quality research is warranted.

The role of probiotics as wound healers: an overall view

A wound is an injury to the skin or damage to the body tissue. The healing process differs between various kinds of wounds. Treatment of hard-to-heal (chronic) wounds becomes challenging for healthcare practitioners, especially if patients have underlying health complications such as diabetes. Infection of wounds is another factor that interferes with the healing process and extends its duration. Active research is being conducted into the development of advanced wound dressing technologies. These wound dressings are intended to manage the exudate, reduce bacterial infection and speed up the healing process. Probiotics have been receiving much attention because of their potential application in the clinical field, especially in diagnostics and treatment strategies of various infectious and non-infectious diseases. The host immune-modulatory response and antimicrobial activity of probiotics are expanding their role in the development of improved wound dressing technology.

The Role of Probiotics in Inflammation Associated with Major Surgery: A Narrative Review

Background: Gut microbiota is well-known for its ability to maintain intestinal homeostasis. However, the disruption of this homeostasis, known as dysbiosis, leads to multiple consequences, including local and systemic inflammation. Surgery-induced inflammation is a major concern for patients, as it leads to many infectious and non-infectious complications. Objective: The purpose of this review was to explore the role of probiotics and symbiotics in surgery-induced inflammation and to determine if their use is effective in combatting inflammation and its complications Methods and Materials: A literature search was conducted, and articles published only in English, until December 2022 were included. The results are reported in the form of a narrative review. Results: The perioperative use of probiotics and/or symbiotics results in lower risk of infectious complications, including reduced rates of surgical site infections, respiratory and urinary tract infections, shorter hospital stays, and fewer days of antibiotic administration. It also contributes to reducing non-infectious complications, as it mitigates systemic and local inflammation via maintenance of the intestinal barrier, improves intestinal mobility, and is associated with lower rates of postoperative pain and anastomotic leak. Conclusions: Restoring gut microbiota after disruptions caused by surgery may accelerate local healing processes, attenuate systemic inflammation, and may thus prove beneficial to certain populations.

Examining the Role of Microbiota-Centered Interventions in Cancer Therapeutics: Applications for Urothelial Carcinoma

Modern advances in genomic and molecular technologies have sparked substantial research on the human intestinal microbiome over the past decade. A deeper understanding of the microbiome has illuminated that dysbiosis, or a disruption in the microbiome, is associated with inflammatory disease states and carcinogenesis. Novel therapies that target the microbiome and restore healthy flora may have value in dampening the immunopathologic state induced by dysbiosis. A narrative review of the literature on the use of microbiota-centered interventions (MCIs) was conducted. Several randomized clinical trials show that MCIs can augment response to immune checkpoint inhibitor (ICI) therapy in patients with metastatic cancer. Clinical trials have also demonstrated that modulation of the intestinal microbiome can enhance recovery and reduce infectious complications in the surgical management of colorectal adenocarcinoma. Overall, these major discoveries suggest future clinical applications of MCIs for a wide range of immune-mediated conditions. These results may also translate to improved patient outcomes in systemic immunotherapy for urothelial carcinoma as well as in patients recovering from radical cystectomy (RC), which is complicated by high infection rates. Further research is needed to evaluate the optimal bacterial composition of microbiota-centered therapies and the specific cellular changes that lead to improved tumor antigen recognition after microbiota-centered therapies.