Depression and anxiety in cancer patients: evidence for different causes.

Fifty-seven cancer patients currently receiving treatment were classified into three groups: (1) those who stated they were depressed/anxious for reasons other than cancer at any time in the past, including the interview day, (2) those who stated they were depressed/anxious solely related to cancer during the past or currently, (3) those who stated they were not depressed/anxious at anytime either in the past or currently, or had only 'normal' symptoms. Patients who were depressed for reasons other than cancer scored higher on self-rated anxiety, depression, and somatization. Patients who were depressed solely due to cancer were not significantly different from those with 'normal' symptoms. The findings suggest the importance of adequate differential diagnosis. The use of anti-depressant treatment with a subset of depressed cancer patients is also suggested.