Patterns of Mastectomy for Invasive Breast Cancer in Queensland — ASN Events

Patterns of Mastectomy for Invasive Breast Cancer in Queensland (#94)

Tony Green 1 , Dannie Zarate 2 , Shoni Colquist 2 , Hazel Harden 2 , Euan Walpole 3
  1. Cairns Private Hospital, Cairns, QLD, Australia
  2. Queensland Cancer Control Analysis Team, Queensland Health, Brisbane, Queensland, Australia
  3. PAH and QEII Hospital Network, Queensland Health, Brisbane, Qld, Australia


Breast conservation surgery (BCS) is the treatment of choice for small breast cancers.  Higher rates of mastectomy in rural compared to urban breast cancer patients are commonly reported in Australia and other countries. In Queensland many rural patients have to travel outside of their Hospital of Health Service of residence for their surgery. Distance has been cited as a barrier to access to quality cancer care.


The rate of definitive mastectomy among 22,124 Queensland women who underwent surgery for removal of invasive breast cancers diagnosed in 2001-2010 was estimated using the Queensland Oncology Repository. Multivariate logistic regression was used to model the variation in mastectomy rate due to age, residence at diagnosis, socioeconomic status, tumour size, and the presence of lobular carcinoma and multifocal tumours.


Mastectomy accounted for 42% of all definitive breast cancer surgeries in this study. In multivariate regression, the rate increased with increasing tumour size and was higher in patients with multifocal tumours and lobular carcinoma. Mastectomy was significantly more common in rural compared to urban women regardless of age or tumour size and histological characteristics (odds ratios [OR] 1.4; 95% confidence interval [CI]: 1.3-1.6). The rate of mastectomy was higher in rural areas even among young (< 40 year-old) women with T1 (< 2 cm) tumours (OR 1.9; CI 1.2 – 3.1). Rural women also had higher rates of mastectomy conversions relative to an initial or index breast conserving surgery (BCS); 19% of rural women initially treated with BCS had a subsequent mastectomy, compared to only 13% of index BCS among urban women.


Mastectomy is more common in rural compared to urban Queensland regardless of age or tumour characteristics. A higher proportion of young rural women who have BCS as the index surgery ultimately have mastectomy as a follow up procedure.