Feasibility and Acceptability of a Positive Psychological Intervention for Patients With Metastatic Breast Cancer: Pre-Post Pilot Study.

Background: Depression and anxiety are prevalent among patients with metastatic breast cancer (MBC), but there are few evidence-based psychological interventions specifically designed for this population.

Objective: This study aimed to assess the feasibility, acceptability, and clinical impact of a multicomponent positive psychological intervention, enhanced with an ecological momentary intervention for symptom management, for patients with MBC.

Methods: We recruited patients with MBC from a National Cancer Institute-designated comprehensive cancer center. Participants completed 5 weekly virtual individual sessions with a study counselor focused on positive emotion regulation skills. Participants also reported physical and psychological symptoms daily between sessions via SMS text messaging. Clinically elevated symptoms triggered a personalized coaching SMS text message tailored to the symptoms reported and the skills learned that week. Primary outcomes were intervention feasibility and acceptability. We also examined pre- to postintervention changes in depression, anxiety, positive affect, and positive emotion regulation skill use. Finally, a subset of participants completed qualitative exit interviews focusing on their experience in the study; interview data were analyzed using rapid qualitative analysis.

Results: We approached 20 patients with MBC, established contact with 15 (75%), received consent from 10 (67%), and retained 9 (90%) patients through the end of the study. Participants were 55 (SD 14.4, range 35-75) years old on average and identified as non-Hispanic White (5/10, 50%), non-Hispanic Black (4/10, 40%), or Latina (1/10, 10%). Participants attended 92% (46/50) of intervention sessions (mean 50, SD 9, range 36-71 min). On average, they completed 85% (SD 18%, range 46%-100%) of daily symptom assessments and received 23 (SD 5, range 13-31) coaching messages. Participants reported high perceived intervention feasibility (mean 4.81/5, SD 0.44), acceptability (mean 4.78/5, SD 0.33), and appropriateness for patients with MBC (mean 4.83/5, SD 0.35), above our a priori cutoff of ≥4. All 9 participants (n=9, 100%) recommended the intervention for other patients with MBC. We observed pre- to postintervention decreases in depression (d=-0.32) and anxiety (d=-0.27) and increases in positive affect (d=0.30) and positive emotion regulation skill use (d=0.99). Rapid qualitative analysis results demonstrate participants' positive experiences with the intervention, as well as suggestions for improvement.

Conclusions: This pilot study supports the feasibility of enrolling and retaining racially and ethnically diverse patients with MBC to this trial, the acceptability of the positive psychological intervention enhanced with ecological momentary intervention, and preliminary intervention impacts on depression, anxiety, positive affect, and positive emotion regulation skill use. A large-scale randomized controlled trial is needed to assess intervention efficacy for outcomes of interest.