Are PROMs sufficient to record late outcome of breast cancer patients treated with radiotherapy? A comparison between patient and clinician reported outcome through an outpatient clinic after 10years of follow up.

AIM: To investigate whether breast cancer patients' visits to an outpatient clinic for late outcome (OCLO) can be replaced by patient reported outcome measures (PROMs), by comparing late toxicity scored at the OCLO with PROMs.
METHODS: All breast cancer patients treated in our institute with adjuvant radiotherapy 10-11years ago were invited to visit the OCLO, and for filling out PROM-questionnaires. Concordance rate between PROMs and OCLO-reported outcome and the percentage of patients with ≥2 degrees difference in toxicity level between patient and clinician was assessed.
RESULTS: 686 of 1029 patients were still alive. 249 patients visited the OCLO, and 341 patients returned a questionnaire. At a group level, patients reported higher toxicity rates than clinicians. The mean concordance for individual patients was 58% between patient and clinician reported outcome. In 2.8%, the clinician reported ≥2 degrees higher toxicity than the patients did, whereas in 6.8% patients reported ≥2 degrees higher toxicity.
CONCLUSION: PROMs do not underestimate late side-effects at a group level. In spite of the low concordance rate, PROMS can be used to identify patients who experience a heavy burden of side-effects, requiring specific attention. Therefore, patients can be spared a visit to the OCLO.