Illness perceptions and quality of life in Japanese and Dutch women with breast cancer.

Knowledge on cross-cultural quality of life (QOL) and illness perceptions may help women with breast cancer cope more effectively. The self regulation model (SRM) guided the current exploratory longitudinal pilot-study. Central to SRM is the perception of health threats and their effects on QOL. Illness perceptions and QOL were assessed in 22 Dutch and 21 Japanese patients with breast cancer who filled out questionnaires before, 1 week, and 8 weeks after the first chemotherapy course. The questionnaires assessed QOL and illness perceptions. Patients' scores were compared with groups of patients with other chronic somatic illnesses (asthma, diabetes). Patients in both samples reported major impact of chemotherapy on global health status, physical functioning, role functioning, emotional functioning, constipation and diarrhea. Differences between Japanese and Dutch patients were limited to social functioning and financial problems. Japanese patients expressed stronger concerns about their illness than Dutch patients. Results of the Japanese and Dutch patients with breast cancer differed from data in patients with asthma on consequences, timeline, concern and emotional response. Results of Japanese patients differed from patients with type 2 diabetes on timeline and concern, whereas Dutch patients differed on timeline and consequences. Japanese and Dutch breast cancer patients have-overall-similar illness perceptions and QOL responses and are aware of the typical characteristics of their disease. The results support the feasibility of cross-cultural psychosocial research in oncology and offer implications for clinical interventions which impact on self-efficacy to empower patients with breast cancer.