Quality control in the locoregional treatment of breast cancer
Breast conserving treatment
BCT is a combination of a surgical excison aiming at
microscopically-free margins and of radiotherapy of the breast. It generally
applies to small (arbitrarily up to 4 cm) unifocal invasive breast cancer. The
to achieve local control,
to preserve breast cosmesis.
The requirements for breast surgery are described in the previous
paragraph. In breast conservation, the surgeon aims at 1 cm free margins.
Requirements for breast radiotherapy are:
high energy photons
simulation and treatment planning
use of appropriate beam modifiers to achieve homogeneity of dose distribution:
dose should not exceed 110% and should not be under 95% of the prescribed dose
avoidance of heart, lung and contralateral breast irradiation
interval between surgery and initiation of radiotherapy should preferably not
exceed 8 weeks.
Indications for BCT should take into account the risk factors for
local recurrence and the determinants for cosmetic outcome
The aim for BCT is to keep the breast relapse rate of invasive
cancer less then 1-2% per annum follow-up (<15% at 10 years)
If known risk factors indicate a higher risk for breast relapse (young age,
incompletely excised infiltrating or in situ cancer, impossibility to deliver
an adequate dose of radiation therapy), either a re-excision (when cosmetically
feasible) or mastectomy has to be considered
OUTCOME MEASURE: The breast relapse rate for invasive cancer after
BCT should not exceed 15% at 10 years.
OUTCOME MEASURE: Excellent or good cosmetic result from a patient's point of
view should be at least 80% at 3 years.
Recommendation: As radiation therapy substantially improves
breast tumour control (by a factor of 2-3), every patient (>95%) with invasive
cancer who have had breast conservation surgery must have had a consultation
with a radiation oncologist to ensure sufficient information has been given on
how to achieve the best tumour control with the least morbidity.