Background
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.
Methods
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.
Results
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.
Conclusion
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.