Understanding the incidence, duration, and severity of symptoms through daily symptom monitoring among frail and non-frail older patients receiving metastatic prostate cancer treatments

Introduction: Older adults with metastatic prostate cancer (mPC) experience high symptom burden associated with treatment. Frailty may exacerbate treatment toxicity. The aim of this study was to explore short-term treatment toxicity in patients with metastatic prostate cancer. Materials and Methods: Older adults with metastatic prostate cancer starting chemotherapy, androgen-receptoraxis targeted therapies, or radium-223 participated in a prospective, multicentre, observational study. Participants self-reported symptoms daily using the Edmonton Symptom Assessment System for one treatment cycle via internet or telephone. The most common moderate-to-severe symptoms (score >= 4), their duration, and the proportion of participants who experienced improvements in symptom severity (score<4) after reporting moderate-to-severe symptoms at baseline were determined using descriptive statistics. Once-weekly symptom questionnaires were administered and analyzed using linear mixed effect models. Symptom incidence, duration, and frailty associations were assessed using t-tests and chi-square tests. Results: Ninety participants completed the study (mean age=77 years [standard deviation=6.1], 42% frail [Vulnerable Elders Survey >= 3]). The most common moderate-to-severe symptoms across cohorts were fatigue (46.8%), insomnia (42.9%), poor wellbeing (41.2%), pain (37.5%), and decreased appetite (37.1%). Poor wellbeing had a higher incidence in frail participants (62.5% in frail vs. 31.4% in non-frail, p=0.039). Symptom duration varied across cohorts and between frail and non-frail participants. Among participants who reported moderate-to-severe symptoms at baseline, no more than 15% improved in any symptom. There were statistically significant improvements in weekly symptoms for fatigue, decreased appetite, and insomnia in the chemotherapy cohort only. Discussion: Limitations include a short follow-up duration, lack of a control group, and few radium-223 participants. Regular symptom monitoring can help clinicians understand temporal patterns and durations of symptoms and inform supportive care approaches.