Table 2.

Main characteristics of studies included in the present systematic review.

Author	Year	Sample	Type of Therapy	Criteria	Results of Therapy
Jiang et al. [25]	2018	99 Patients: 64 probiotic 35 placebo	Cisplatinum plus radiotherapy 70 Gy	National Cancer Institute’s Common Terminology Criteria for Adverse Events	Reduces the severity of OM through changes in the gut microbiome
De Sanctis et al. [26]	2019	68 Patients: 32 probiotic 36 placebo	Cisplatinum plus radiotherapy 68 Gy	National Cancer Institute’s Common Terminology Criteria for Adverse Events	No difference between the two groups
Mirza et al. [27]	2022	46 Patients: 23 probiotic 23 placebo	Radiotherapy with or no chemotherapy 60–70 Gy	National Cancer Institute’s Common Terminology Criteria for Adverse Events	Reduces the severity of OM