Mental adjustment to cancer: its measurement and prognostic importance.

Can the mental adjustment of patients to cancer influence the course of their disease? This question is considered in a critical review of relevant studies. Salient problems in this field of research are identified and basic methodological requirements outlined. The few systematic, prospective investigations which meet these requirements show evidence for an association between mental adjustment to cancer and subsequent outcome in patients with 'early'--ie non-metastatic disease. The evidence, however, should be regarded as provisional rather than conclusive. A definitive answer will require further carefully controlled long-term follow-up studies. In such studies, a crucial methodological issue is the measurement of mental adjustment to cancer. Hitherto, this has been based solely on clinical assessments. The development of a new measure of mental adjustment to cancer is reported. The MAC scale is a 40-item self-rating questionnaire. Initial results based on a study of 235 patients with a variety of cancers indicate that the scale is acceptable to patients, easy to administer in busy oncology clinics, reliable and stable over time. Its validity as measured by spouses' ratings appears satisfactory. Further evaluation is required. These preliminary results suggest that the MAC scale is a suitable, easily replicable method of measuring adjustment to cancer in studies of large numbers of patients.