Breast cancer surgery margins are essential

A paper just published in the International Journal of Clinical Practice clarifies the importance and parameters of operating to excise a margin of healthy tissue around a breast tumor. The authors state:

"In breast-conserving surgery, the width of free margin around a tumour to ensure adequate excision is controversial. The aim of this study was first to evaluate the frequency of residual disease in wider excision specimens in patients who undergo further surgery because of close margins of < 5 mm."

The assessed 303 patients undergoing wider excision for the presence of residual disease, and this was tested for association with the width of the initial free margin. What did they find?

""With a free margin of 2 mm or more from invasive tumour, the probability of finding residual disease was 2.4% [versus 35.3%]. The probability of residual disease was higher for ductal carcinoma in situ (DCIS) and did not decline with increasing the free margin width...Our results clearly show a relationship between the width of the free margin and the likelihood of finding residual disease at further surgery."

Patients who choose breast conserving surgery for an invasive tumor should ascertain that their surgeons excise with a free margin of at least 2 mm. The authors state in conclusion:

"This study has demonstrated that in patients undergoing BCT, a free margin of 2 mm from invasive tumour is associated with a low risk of residual disease. A free margin of up to 5 mm from DCIS is associated with residual disease in one-third of patients. Large tumour size, as determined preoperatively by ultrasound, and lobular cancer type are associated with close margins and these patients should be counseled at the time of first surgery concerning the higher risk of further excision and mastectomy."