Table 3.

Qualitative analysis for all the included studies amongst the identified trials.

#	Author, publication year (reference)	Population	Intervention	Control	Sample Type	Findings
1	Nettleton, 2004 [41]	Breast cancer (BC) survivors	1. Diet+Soy protein isolate (S); 2. Diet+S+Probiotics (S+P) 3. Diet+Milk protein isolate (M); 4. Diet+M+Probiotics (M+P) *Four 42 d diet plan in random order	-	Plasma, 24 hr urine	1. No changes in plasma phytoestrogen between groups. 2. No changes between S and S+P diets due to plasma phytoestrogen levels and number of equol producers. 3. Probiotic supplement does not generally affect plasma isoflavones.
2	Nettleton, 2005a [42]					1. Soy consumption tended to increase urinary 2-OHE (p = 0.07) and 16α-OHE1 (p = 0.11) but had no effect on urinary 2:16OHE1. 2. Soy consumption increased 2:16OHE1 only in women who are equol producers.
3	Nettleton, 2005b [43]					1. Soy, probiotic supplements, or equol producer status had no impact on hormone levels. 2. Neither presence of cancernor or equol producers changed the effects of soy or probiotics.
4	Donders, 2015 [44]	Postmenopausal BC survivors on aromatase inhibitors with severe atrophic vaginitis	Vaginal use of 0.03 mg estriol and lactobacilli (1 tablet of Gynoflor® for 28 d) combination	-	Vaginal smear	1. Lactobacillary grades (p < 0.001) and aerobic vaginitis (p < 0.01) improved during treatment. 2. Leukocytes (p < 0.01) and parabasal cells (Ptrend < 0.01) dropped at the final visit. 3. Candida may develop soon after its use but rapidly disappears again upon their prolonged use.
5	Marschalek, 2017 [45]	Postmenopausal BC patients receiving chemotherapy, with vaginal atrophy and an intermediate vaginal microbiota (Nugent score 4–6)	Twice daily oral capsules for 2 weeks	Oral placebo having lactose	Vaginal smear	1. Observed a positive influence on vaginal microbiota in 63% women in the intervention group and 36% women in the control group. 2. There was a shift in Nugent score towards normal microbiota levels in the intervention group and significant deterioration in the score in the control group.
6	Vafa, 2020 [46]	BC survivors with breast-cancer-related lymphedema (BCRL)	A calorie-restricted diet plus a synbiotic (CRS) daily for 10 weeks	Diet plus a placebo (CRP) and control	Body fluid	1. A decrease in the total quality-of-life score (p = 0.004), and its psychosocial (p = 0.022) and functional (p = 0.002) domain scores 2. A decrease in edema volume (p = 0.002) and BMI (p < 0.001) in comparison to controls.
7	Vafa, 2022 [47]	Overweight or obese BC survivors with BCRL	Low-calorie diet (LCD) plus a synbiotic daily for 10 weeks	LCD plus a placebo	Serum	1. Had beneficial effects on increasing serum TGF-β, IL-10, and adiponectin levels in women with BCRL, but no significant differences. 2. Edema volume decreased in the synbiotic group. 3. BW, BMI, BF%, and WC decreased in both groups.
8	Totmaj, 2020 [48]					1. A significant reduction in leptin (p = 0.003) and TNF-α (p = 0.039) between the groups. 2. No significant effects in hs-CRP (p = 0.55) and IL-1β (p = 0.118) between study groups.
9	Pellegrini, 2020 [49]	Overweight BC survivors	Mediterranean diet for 4 mo. + Probiotics for first 2 mo.	Mediterranean diet for 4 mo. only	Serum, stool	1. Number of bacterial spp. (p = 0.01) and diversity (p = 0.004) significantly increased only with intervention. 2. Bacteroidetes:Firmicutes ratio decreased with intervention and increased in controls (p = 0.004). 3. Significant improvement in metabolic and anthropometric parameters (BW, BMI, glucose, and insulin) compared with Mediterranean diet alone
10	Lahiji, 2021a [50]	Overweight or obese postmenopausal BC survivors	LCD + 109 CFU/day of synbiotics for 8 weeks	LCD + Placebo	Serum	1. Insignificant reducing effects on glycemic profile (serum insulin, fasting plasma glucose, HbA1c, HOMA-IR), IGF-1, and sex hormones (estradiol, testosterone, DHEA-S, and SHBG).
11	Lahiji, 2021b [51]					1. Increased adiponectin (p < 0.001), reduced TNF-α (p < 0.001) and hs-CRP (p < 0.001) compared to placebo.
12	Juan, 2022 [52]	BC patients who underwent 4 cycles of docetaxel-based chemotherapy	Twice daily, 3 capsules (0.84 g)/time of probiotics during chemotherapy at a cycle of 21 d for a total of four cycles	Placebo	Plasma, stool	1. Supplement significantly decreased the CRCI, improved the allover cognitive functions, changed gut microbial, and modulated 9 plasma metabolite changes. 2. Metabolites p-mentha-1,8-dien-7-ol, linoelaidyl carnitine, and 1-aminocyclopropane-1-carboxylic acid negatively correlated with rate of CRCI.
13	Juan, 2021 [53]					1. Bacteroides (p < 0.001) and Anaerostipes (p < 0.001) changes inversely correlated with change in LDL. 2. Reduced BW, BF%, and LDL, and minimized metabolic changes and gut dysbacteriosis.