Study objective: There is a need to explore how patient-tailored integrative oncology (IO) programs reduce emotional distress. This study set out to bridge the IO research gap between non-specific, quality of life-related and specific emotionalrelated concerns in chemotherapy-treated patients. Methods: This pragmatic, prospective and preference-controlled study examined patients attending an integrative-physician consultation and weekly IO treatments during adjuvant/neo-adjuvant chemotherapy for localized cancer. Patients choosing to attend ≥4 IO sessions (highly adherent to integrative care, AIC) were compared to low AIC patients using the ESAS (Edmonton Symptom Assessment Scale) anxiety, depression and sleep; and the EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire) emotional functioning scale, at baseline, 6 and 12 weeks. Emotional distress was assessed by ESAS anxiety and depression, considered as the primary study outcomes. Results: Of 439 participants, 260 (59%) were high-AIC and 179 low-AIC, both with similar baseline demographic and cancer-related characteristics. At 6 weeks, high-AIC patients reported greater improvement on ESAS sleep (p = 0.044); withingroup improvement on ESAS anxiety and; and EORTC emotional functioning. Compared with low-AIC, high-AIC patients showed greater improvement on ESAS depression (p = 0.022) and sleep (p = 0.015) in those with high baseline ESAS anxiety scores (≥7); and ESAS anxiety (p = 0.049) for patients moderately anxious (4-6) at baseline. Conclusions: High-AIC was associated with significantly reduced anxiety, depression and sleep severity at 6 weeks, especially those with high-to-moderate baseline anxiety levels. These findings reduce the research gap, suggesting specific emotional-related effects of IO.