BOSTON--Radical mastectomy is no longer routine for women with
breast cancer, but the indications for breast conservation are
still being debated by surgeons who fear the risk of breast cancer
recurrence. At the 48th Annual Cancer Symposium, sponsored by
the Society of Surgical Oncologists, a panel of physicians discussed
patient selection criteria for breast conservation surgery.
Monica Morrow, MD, of the Northwestern University Medical School,
emphasized the need to consider breast conservation in all women
with breast cancer. If given the opportunity to choose, she said,
"80% of all women greater than 70 years of age will select
breast conservative techniques. It's a physician perception that
elderly women don't care about preserving their breasts."
She recommends magnification mammography to select patients for
breast conservation and plan the extent of resection. Criteria
for selection include the size, depth, and location of the tumor,
in addition to the histologic features of the cancer. Performing
wide excision is not always necessary, Dr. Morrow said.
Minor variations in cosmetic outcome are seen on the basis of
breast size, but it is really the tumor-to-breast-size ratio that
is important, not absolute size, she said. The amount of tissue
resected is the main determinant of cosmetic outcome, and a limited
resection results in good to excellent cosmesis in 90% of patients.
Surgeons differ on just how wide an excision needs to be to counterbalance
the risk of local recurrence. "Excisional biopsy is not an
adequate therapeutic event," argued David S. Robinson, MD,
of the Sylvester Comprehensive Cancer Center, Miami.
He recommends breast conservation therapy only for tumors less
than 3 cm in diameter, and with a margin of at least 2 cm for
extensive ductal carcinoma in situ (DCIS).
All the surgeons on the panel recommended dialogue among the radiologists,
pathologists, and plastic surgeons in order to plan the extent
of resection.
Risk Factors for Recurrence
Only a small percentage of patients treated with conservative
surgery and radiation therapy develop recurrence in the treated
breast, said Stuart J. Schnitt, MD, associate director of surgical
pathology, Beth Israel Hospital, and associate professor of pathology,
Harvard Medical School.
Potential risk factors for local recurrence include the extent
of surgical resection, extensive intraductal component (EIC),
and microscopic margins of excision, he said.
EIC is defined as infiltrating ductal carcinoma with prominent
DCIS within the tumor and DCIS in adjacent tissue. Dr. Schnitt
believes that mammography is "critically important"
in determining whether a patient is positive for EIC, whether
there are diffuse malignant calcifications, and hence whether
the patient is a candidate for breast conservation therapy.
Though EIC-positive tumors are more likely to have margin involvement,
the presence of an EIC is not ipso facto a contraindication to
conservative surgery with radiotherapy, Dr. Schnitt said. Rather,
it is an indicator that a wider excision may be necessary to achieve
optimal local control.
