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Surgeons Vol.2 Issue 3: Blake
Cady, MD, FACS
Edited comments by Dr Cady
Relationship between local tumor control and
survival
Strong evidence in breast and other cancers shows that no matter
how radical the local treatment — surgery or surgery plus
radiation therapy — cure rates are not decreased by high
local recurrence rates. Local recurrence is an indicator of the
biology of the tumor, not a governor of the outcome.
In the NSABP-B-06 trial, there was more than a 40 percent local
recurrence rate in the group treated with lumpectomy alone, but
for the three groups — mastectomy, lumpectomy and radiation
or lumpectomy alone — there was no statistical difference
in survival.
Until the two recent trials from Denmark and British Columbia,
the data have been totally consistent — no matter what measures
were taken for local control, it did not change survival. The Danish
trials comparing mastectomy, adjuvant CMF and axillary dissection
with or without radiation therapy seem to contradict all others,
but are seriously flawed. There was a 45 percent rate of axillary
recurrence after axillary dissection that has never been seen before.
Because they took out only six or seven nodes when they did the
axillary dissection, there are serious concerns about improper
staging in the Danish trial. The Danish trial is different in that
all the patients received adjuvant CMF. In the era of routine adjuvant
chemotherapy, therefore, it’s possible that the standard
assumption in surgical oncology may have to be looked at more carefully.
In the trial by Veronesi comparing quadrantectomy to quadrantectomy
plus radiation therapy, there was no difference in overall survival
for the patients with negative nodes. The patients with positive
nodes all received chemotherapy, and at about five years, the two
arms split showing an advantage for the group treated with radiation
therapy. That’s consistent with data from the Danish trials.
The breast cancer trials comparing mastectomy to lumpectomy plus
radiation have shown no difference in survival, and yet there are
tremendously higher local recurrence rates. The data is consistent.
Some small cancers can be treated with local excision alone and
no radiation. I’m still convinced that the “radicalness” of
local treatment governs local recurrence, but not survival.
I tell breast cancer patients that no woman pays with her life
for saving a breast. A woman, even with marginal indications for
lumpectomy, won’t pay with her life but will pay with a higher
local recurrence rate. She might need a mastectomy later on, but
it’s not going to negatively affect her survival.
Radiation therapy in women with DCIS
In our unit, we’ve designed some protocols based on the
Van Nuys Prognostic Index. We only radiate 20 percent of our DCIS
patients. Due to the extensive nature of their disease or patient
choice, 30 percent of our patients require mastectomy. Another
30 percent are treated by local excision alone with reexcision
to achieve a one-centimeter margin — Mel Silverstein’s
criteria.
DCIS is not a homogeneous disease; there are a variety of biological
patterns and manifestations. The median diameter of the average
DCIS detected today by mammography is only eight or nine millimeters,
and those patients should not be treated with radiation therapy.
Revised American Joint Committee on Cancer (AJCC)
staging
Nodes are no longer just nodes, because there are micrometastases
and submicrometastases. It is distressing that many oncologists
are treating patients systemically for submicrometastases, which
is why the new AJCC staging system is so important.
Cells found in a node that are less than 0.2-mm, largely by IHC,
should not be used for therapeutic decisions. Those are considered
N0 in breast cancer. That type of information should not be used
to make therapeutic decisions — either for axillary dissection,
chemotherapy or radiotherapy. We don’t know what those things
mean.
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