Therapy Dog Presence During Chemotherapy in a Day Chemotherapy Unit: A Prospective Pilot Comparative Pre-Post Study

Introduction Therapy dog visits have been introduced in oncology settings as supportive, non-pharmacological interventions. However, evidence regarding their use among adult patients receiving chemotherapy in day hospital settings remains limited. This study evaluated immediate changes in patient-reported symptoms and selected respiratory parameters during chemotherapy in the presence or absence of a therapy dog. Methods This prospective pilot comparative pre-post study with room-level allocation was conducted in the Day Chemotherapy Unit of the "Metaxa" Memorial Anticancer Hospital, Greece, between January 19 and March 27, 2026. Seventy adult oncology patients receiving scheduled chemotherapy were included: 35 in the therapy dog group and 35 in the control group. The intervention consisted of the presence of a certified therapy dog and trained handler for approximately 20 to 30 minutes. The control condition consisted of neutral procedural presence without a therapy dog or active supportive intervention. Patient-reported anxiety, relaxation, and dyspnea were assessed before and after the session using 0-10 numerical rating scales. Peripheral oxygen saturation and respiratory rate were also recorded. Change scores were compared between groups, and exploratory adjusted linear regression models were performed. Results Compared with the control group, the therapy dog group showed a greater reduction in anxiety and a greater increase in relaxation. Respiratory rate also decreased more in the therapy dog group, although this finding was interpreted as exploratory because respiratory rate differed between groups at baseline. The between-group mean difference in change score was -1.23 for anxiety, 1.83 for relaxation, and -0.49 breaths/min for respiratory rate. No statistically significant between-group differences were observed for dyspnea or peripheral oxygen saturation. Exploratory adjusted analyses were consistent with the unadjusted findings for anxiety, relaxation, and respiratory rate. Conclusions Therapy dog presence during chemotherapy was associated with immediate favorable changes in anxiety and relaxation scores in this prospective pilot comparative pre-post study. Findings for respiratory parameters were less consistent and should be interpreted cautiously. These exploratory results support the feasibility of therapy dog presence in a day chemotherapy setting and may inform the design of larger controlled studies.