Patient symptoms, confidence, and adherence during the first 8 weeks of targeted oral anticancer agent treatment

We aimed to understand patients' initial experiences with targeted oral anticancer agents (OAAs). We investigated symptoms experienced and how symptom severity affected patient confidence to manage and seek care for symptoms and OAA adherence.

We conducted a longitudinal prospective cohort study of patients during the first 8 weeks of targeted OAA treatment at an NCI-designated cancer center. Participants completed patient-reported outcome measures (PROMs) online at three timepoints. Descriptive statistics quantified demographics, cancer characteristics, symptom severity, confidence, and OAA adherence. Logistic regression was used to estimate confidence and adherence by each symptom at each timepoint. Mixed effects logistic regressions accounted for repeated measures and time effects on outcomes.

Participants (n = 59) reported severe symptoms at all timepoints. Tiredness and drowsiness were most frequently reported as severe. Participants' confidence increased from timepoint 1 to 3. Most participants reported high confidence (61-86%) and excellent adherence (75-80%) across all timepoints, but 20-25% had less than excellent OAA adherence. High confidence to manage symptoms was positively associated with older age. Confidence to manage symptoms was inversely related to the severity of depression, tiredness, drowsiness, constipation, and tingling/numbness.

Confidence to manage symptoms increased with time on OAAs, but severe symptoms persisted. Although self-reported OAA adherence was high, a notable number of participants reported suboptimal adherence. Relationships between confidence, symptom severity, and adherence should be identified in clinical settings to evaluate patients who may need extra clinical support during OAA treatment.