OBJECTIVES: To depict current clinical practice in the treatment of local, locally advanced and metastatic (stages I/II, III and IV respectively) Breast Cancer in Greece. METHODS: A group of 7 Breast Cancer experts gave information about current therapeutic approaches and their frequency of usage in the treatment of breast cancer patients. Data were derived from retrospective patient hospital records analysis for the years 1998-2000, validated by expert panel opinion. The consensus method used was a modified form of the Rand Version of the Nominal Group Technique. For severity stages I/II and III analysis was conducted for subgroups of patients according to menopausal and estrogen/progesterone receptor status. Results were reported in the form of "decision analysis trees" for each patient group. Probability distributions were based on the frequency of usage of each treatment pathway. For Stage IV patients, analysis was conducted regardless of menopausal and ER/PR status. Clinical practice was reported at sequential lines of patient management in frequency tables depicting usage ratios of each therapeutic pathway. RESULTS: Treatment appears more standardized for disease stages I,II, III. The most frequently used therapy is surgery followed by radiotherapy and adjuvant therapy. Stage III patients are more likely to receive neo-adjuvant therapy. ER/PR status determines the choice of adjuvant therapy, as patients with positive receptors are most likely to receive endocrine therapy alone or in combination with chemotherapy. In Stage IV, observed treatment pathways present varying sequential usage across patients, with systemic chemotherapy, endocrine therapy and radiotherapy as the most frequent clinical options. CONCLUSIONS: The model seems a feasible approach in depicting current clinical practice in Greece. It can be used as tool for clinicians and decision makers for monitoring health care costs, estimating cost of illness, and evaluating the introduction of new therapies in the management of Breast Cancer patients in Greece.