BREAST-CANCER IN WESTERN-AUSTRALIA IN 1989 .2. DIAGNOSIS AND PRIMARY MANAGEMENT

This study was designed as a population-based study of all cases of br east cancer diagnosed in Western Australia (WA) in 1989. Cases were id entified from the State Cancer Registry and from computerized hospital inpatient records. Data were obtained from the records of surgeons an d oncologists managing the patients, hospital medical records and path ology and cytology reports. A total of 701 tumours in 692 women were t reated by 105 different surgeons of whom 25 saw 10 or more cases. Over 70% were proven by cytology or biopsy within 2 weeks of presentation to a doctor. The first diagnostic investigation was fine needle aspira tion in 45%, open biopsy in 28% and diagnostic mammogram in 24.4%. A d efinitive procedure involving breast conservation was performed in 31. 3% of patients with operable tumours; 35.6% of those under 50 years of age. If axillary dissection or sampling was part of such treatment, 9 3.5% of those under 50 years and 75% of those 50 years and over had ra diotherapy to the residual breast. Although less than one-third of pat ients were referred to a medical oncologist almost a half had adjuvant systemic therapy (92% of node positive and 23% of node negative patie nts). Tamoxifen was prescribed as part of adjuvant therapy in 93% of t hose over 50 years and cyclophosphamide, methotrexate and 5-fluorourac il in 71% of those under 50 years. Less than 10% of patients treated w ith mastectomy and axillary dissection had postoperative radiotherapy to the chest wall and drainage areas. The patterns of care of patients with breast cancer in WA prior to the introduction of population-base d mammographic screening have been established. They indicate a signif icant influence of clinical trials on practice with a more ready accep tance among surgeons of the results of randomized studies of non-surgi cal treatment than of those which relate to operative practice.