Self-evaluation of Adjuvant Chemotherapy-Related Adverse Effects by Patients With Breast Cancer

Patient perspective on chemotherapy-related adverse effects is being increasingly acknowledged both in experimental clinical trials and in clinical practice.

To evaluate a 10-item, paper questionnaire derived from the US National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 for patient-reported chemotherapy-related adverse effects.

Prospective, single-arm study of 604 women with breast cancer receiving standard adjuvant chemotherapy conducted at 11 outpatient oncology clinics at academic and nonacademic Italian hospitals between January 2011 and October 2013. The CTCAE version 4.0 definitions of grade of severity for nausea, vomiting, constipation, anorexia, dysgeusia, diarrhea, fatigue, pain, paresthesia, and dyspnea were translated into Italian and rephrased. Questionnaires were administered after the first and third cycle of chemotherapy. Adverse effect information was also extracted from the medical records to compare with patient-reported data.

Differences in adverse effect-reporting between paired questionnaires and agreement between patient and physician adverse effect-reporting (grade 0 vs grade ≥1) were studied. Linear regression was used to study the effect of the number of patients enrolled at each institution on the magnitude of discrepancy in adverse effect-reporting between patients and physicians.

A total of 604 women (median age, 53.4 years; interquartile range, 45.0-62.7 years) were enrolled. The number of patients enrolled at each site varied between 6 and 236. Three patients withdrew consent prior to starting the first cycle of adjuvant chemotherapy. After cycle 1 of adjuvant chemotherapy, 596 patient questionnaires were collected, and 581 patient questionnaires were collected after cycle 3. Of the questionnaires collected, 594 and 573 had corresponding questionnaire results extracted from medical records at the same time point. The median (interquartile range) percentage of completed questionnaire fields was 82% (80%-88%) for both the first and third cycle questionnaires, and the results of the 2 patient questionnaires showed a reduction in vomiting (severity), diarrhea (both incidence and severity), and pain (both incidence and severity), as well as a statistically significant increase in dysgeusia (both incidence and severity) and dyspnea (both incidence and severity) in the second patient-completed questionnaire. The frequency and severity of chemotherapy-related adverse effects were consistently greater in patient-reported data than physician-reported data. As a result, interrater agreement was low for most adverse effects, ranging from 0.10 for anorexia to 0.54 for vomiting (Cohen κ statistic). There was a strong and significant positive correlation between the magnitude of the discrepancy in the frequency of reporting adverse effects and the number of patients enrolled at each site.

Adherence to reporting adjuvant chemotherapy-related adverse effects using the CTCAE system is high in women undergoing adjuvant chemotherapy for breast cancer. Workload may contribute to agreement discrepancies by limiting the physician-patient relationship.