Published online Jun 6, 2019. doi: 10.12998/wjcc.v7.i11.1253
Peer-review started: March 15, 2019
First decision: March 29, 2019
Revised: April 7, 2019
Accepted: April 18, 2019
Article in press: April 19, 2019
Published online: June 6, 2019
The incidence of gastrointestinal (GI) tumors is increasing year by year, and its pathogenesis is closely related to the intestinal flora. At present, the use of antibiotics is very common in the clinic. And cancer patients with low immunity are vulnerable to all sorts of infections, such as respiratory tract infections and urinary tract infections. Moreover, cancer patients easily run into fever and neutropenia induced by myelosuppression. Therefore, antibiotics are used extensively and even overused in many conditions. However, because of the special anatomical location of the gastrointestinal tract, the antibiotic usage will bring changes to the intestinal flora. Besides, with the expanding popularity of immunotherapy, various factors affecting the efficacy of immune checkpoint inhibitors (ICIs) have been extensively explored, including cancer-associated inflammation and the local and systemic factors that lead to immunosuppression. Some biomarkers for ICIs, including the expression of PD-L1, tumor mutation load, and microbiota, also have been investigated, and many studies have confirmed that gut microbiota can affect the efficacy of immunotherapy. But further studies on the influence of antibiotics directly on immunotherapy are rare. In this review, we discuss the relationship between GI tumors and antibiotics, the current status of immunotherapy in GI tumors, and the influence of antibiotics on immunotherapy.
Core tip: With the widespread use of immunotherapy for almost all types of cancers and the extensive usage of antibiotics in many countries, the association between antibiotics and immunotherapy deserves an investigation based on some studies which showed that the gut microbiota plays an important role in immunotherapy. We reviewed the relevant papers and found that antibiotics may attenuate the effect of immunotherapy.