The main objective of this study was to compare the reporting of health status and symptom severity, for a set of core symptoms related to imatinib therapy, between chronic myeloid leukemia patients and their treating physicians. Patients were asked to complete a questionnaire including questions on symptom severity and health status. The symptoms assessed were: abdominal discomfort, diarrhea, edema, fatigue, headache, muscle cramps, musculoskeletal pain, nausea and skin problems. The physicians were asked to complete a questionnaire for each of their patients entering the study. Four hundred twenty-two patients were included in the study. All respective paired physicians (n=29) completed the questionnaire, and thus the analyses are based on 422 patient-physician dyads. Agreement on symptom ratings ranged from 34% (for muscle cramps) to 66% (for nausea). For all symptoms, patients reported higher severity more often than their physicians. The three symptoms whose severity was most frequently underestimated by physicians were fatigue (51%), muscle cramps (49%) and musculoskeletal pain (42%). Health status was overestimated by physicians in 67% of the cases. Physicians and their patients with chronic myeloid leukemia often disagree in their ratings of the patients' symptom severity. Most typically, physicians tend to underestimate symptom severity and overestimate the overall health status of their patients. Current findings support the use of patient-reported outcome measures as a possible means to enhance the management of patients with chronic myeloid leukemia.