Objective: To investigate the association between cancer patients' reluctance for emotional disclosure to their physician and underrecognition of depression by physicians. Methods: Randomly selected ambulatory patients with lung cancer were evaluated by the Hospital Depression and Anxiety Scale (HADS), and those with scores over the validated cutoff value for adjustment disorder or major depressive disorder were included in this analysis. The data set included the responses to the 13-item questionnaire to assess four possible concerns of patients in relation to emotional disclosure to the treating physician ("no perceived need to disclose emotions", "fear of the negative impact of emotional disclosure", "negative attitude toward emotional disclosure", "hesitation to disturb the physician with emotional disclosure"). The attending physicians rated the severity of depression in each patient using 3-point Likert scales (0 [absent] to 2 [clinical]). Depression was considered to be underrecognized when the patients had a HADS score above the cutoff value, but in whom the depression rating by the attending physician was 0.Results: The HADS score was over the cutoff value in the 60 patients. The mean age was 65.1 ± 10.0, and 82% had advanced cancer (Stage IIIb or IV or recurrence). Depression was underrecognized in 44 (73%) patients. None of the four factors related to reluctance for emotional disclosure was associated with the underrecognition of depression by the physicians. None of the demographic or cancerrelated variables were associated with depression underrecognition by physicians. Significance of results: The results did not support the assumption that patients' reluctance for emotional disclosure is associated with the underrecognition of depression by physicians. © 2009 Copyright Cambridge University Press.