BackgroundThere is a lack of psychotherapeutic trials of treatments of comorbid depression in cancer patients. Our study determines the efficacy of a manualized short-term psychodynamic psychotherapy and predictors of outcome by personality and quality of the therapeutic relationship.Methods/designEligible breast cancer patients with comorbid depression are assigned to short-term psychodynamic psychotherapy (up to 20 + 5 sessions) or to treatment as usual (augmented by recommendation for counseling center and physician information). We plan to recruit a total of 180 patients (90 per arm) in two centers. Assessments are conducted pretreatment, after 6 (treatment termination) and 12 months (follow-up). The primary outcome measures are reduction of the depression score in the Hospital Anxiety and Depression Scale and remission of depression as assessed by means of the Structured Clinical Interview for DSM IV Disorders by independent, blinded assessors at treatment termination. Secondary outcomes refer to quality of life.DiscussionWe investigate the efficacy of short-term psychodynamic psychotherapy in acute care and we aim to identify predictors for acceptance and success of treatment.Trial registrationISRCTN96793588