Background: RWD denotes data accumulated via electronic health records as well as cutting edge technology paired with consumer mobile devices. Artificial intelligence (AI) incorporates the use of algorithms and machine learning (ML) software to analyze complex medical data, improving the knowledge of cancer journeys. PRO on 256 BC patients (pts) survey repliers, users of Belong.life, a worldwide social media application for cancer pts, are presented. Methods: From 11/2018 to 01/2019, 256 pts replied to a 37 questions’ survey which included information regarding clinical and emotional S/E, FT and CM use. Results: 98 pts (38%) were < 50 years of age, 158 (62%) > 50 years. Most of the pts (163, 64%) were diagnosed within 2017-8. Most pts had Stage 1 (83 pts,32%) and 2 (94 pts,37%) and 71 pts (28%) had Stage 3-4. 154 (61%) had neo-adjuvant anthracyclines-based treatments, followed by a taxane (docetaxel/paclitaxel). 149 of 256 pts (58%) reported clinical S/E: nausea and vomiting in 77 pts (52%), fatigue in 63 pts (42%), hair loss in 42 pts (28%) and body pain and neuropathy in 13 pts each (8.8%). 90 pts (35%) described various emotional symptoms: depression in 32 pts (35.6%), anxiety 13 (14.4%), ‘up and down’ feelings in 20 pts (22 %). FT was experienced by 100/208 pts (48%). FT was most prevalent in ages 35-50 (51/85pts, 60%) than in 51-65 (41/100pts, 41%). Main reported causes in both groups were loss or absence from work (33% and 51%) and treatment copayments (40% and 21%). CM use was reported by 42/256 pts (16.4%). Most common CM were nutritional, multivitamins, supplements and CBD oil use. ML documented a strong relationship between BC recurrence in 55/256 pts (21.5%), FT in 25/55 pts (45.5%) and CM use in 9/25 pts (36%) vs no FT in 3/30 pts (10%). Conclusions: 256 BC users of the Belong application reported on clinical and emotional S/E, FT and CM use. The high incidence of emotional S/E stresses the need for individualized attention. FT was most prevalent in the younger age group (35-50yrs) due to work loss and treatment copayments. A significant relationship was determined by ML techniques on those patients experiencing BC recurrence, FT and CM use.