BALTIMORE--A review of randomized trials shows that local recurrence
rates for breast-conserving therapy are comparable to those for
mastectomy for early-stage patients, Irene Gage, MD, said at a
conference sponsored by Johns Hopkins Medical Institutions.
Ipsilateral breast recurrence is seen in about 6% of breast-conservation
patients at 5 years and in about 9% at 10 years. Most of these
occur in the same quadrant of the breast as the primary tumor
site. These true recurrences and marginal misses are observed
in the early years after treatment, while recurrences elsewhere
in the same breast are more frequent between 5 and 10 years, said
Dr. Gage, a radiation oncologist at the Johns Hopkins Oncology
The main risk of recurrence after breast-conserving therapy, she
emphasized, is distant failure.
"The risk of an ipsilateral breast recurrence remains fairly
constant in the first decade following treatment, and thus patients
require continuous monitoring and mammography for years after
their initial treatment," she said.
Ipsilateral breast recurrence is accompanied by distant metastases
in a minority of cases, and most recurrences are operable. Salvage
mastectomies produce 5-year survival rates ranging from 55% to
85%, according to studies cited by Dr. Gage.
The increased risk of ipsilateral breast recurrence may be associated
with treatment, pathology, and patient selection issues. For example,
an extensive intra-ductal component is a pathologic feature associated
with an increased risk of breast recurrence in some series. Other
path-ologic factors like lymphatic vessel invasion may be important,
but the literature is retrospective, controversial, and inconclusive,
Treatment decisions such as degree of surgery may influence the
recurrence rate, Dr. Gage said. Quadrantectomy or wide excision
of the primary tumor appears to result in fewer recurrences than
lumpectomy or gross excision.