To assess within a region, the management of operable breast cancer, treatment outcomes and agreement with published national treatment guidelines.

A prospective longitudinal study of consecutive patients presenting with breast cancer to participating clinicians was conducted for the purpose of quality assurance and to facilitate uptake of treatment guidelines. Annual feedback of individual patterns of care was provided to contributing clinicians. Written consent was obtained from all participants.

Over 15 years, 5700 subjects were enrolled, representing an estimated 95% of incident breast cancers in the region. There were 3819 (81%) subjects with unilateral invasive disease, 481 (10.2%) with DCIS, 246 (5%) with bilateral invasive disease; 83 subjects had de novo metastatic disease. There were 28 male subjects. Of the female subjetcs with unilateral invasive disease 1885 (49.4%) had breast conserving surgery (BCS) and 1934 (50.6%) underwent mastectomy (Mx). Subjects living in rural areas were less likely to have post-BCS adjuvant radiotherapy. 1805 (95.7%) of subjects who underwent BCS were offered RT. Of the 472 female patients with positive axillary lymph nodes, aged under 50 years, 467 (98.9%) were offered adjuvant chemotherapy. There were clear changes in the pattern of practice over the course of the study. BCS increased over time. CMF was intially the most commonly used chemotherapy regimen, but was replaced by anthracycline-based regimens and subsequently taxane-based regimens. The number of subjects who received an aromatase inhibitor increased rapidly after 2002.  With a median follow up of 8.5 years, of 3819 subjects with unilateral invasive disease, 310 were current status unknown, 605 patients had died with 349 breast cancer related deaths, there were 140 patients remain alive but with disease; 2764 (78.8%) remain alive and free from relapse. 

Long term follow-up of a breast cancer cohort is feasible. Overall, there was high concordance of treatment received with published guidelines with but some variation between rural and metropolitan residents.