George A. Knaysi, MD Richmond Surgical |
All cancers are caused by abnormalities in a person’s
genes. Some of these abnormalities
(mutations) are inherited and some are acquired by life activities, like
smoking. While breast cancer has become more common in the forty years since I
began to practice breast surgery in Richmond, the cause for the increasing
incidence is unclear. For example, we
know that the risk is elevated in women who are obese or who drink alcohol, but
the increased risk is small. Every week we see someone with breast cancer who
has a negative family history, but seems to do all of the right things relative
to diet and lifestyle. Why does this happen? Unfortunately, we still don’t
know.
It takes multiple genetic abnormalities to eventually
result in cancer. These do not happen
all at once, and some of the changes might begin many years before the cancer
actually develops. While it appears
there are four major types of breast cancer, there is significant genetic variation
even within each type. When we have a clearer understanding of this, drugs can
be designed to stop the abnormalities from developing or progressing. When that happens, breast cancer will become
a medical, not surgical illness. That scientific breakthrough will change
everything – and eventually it will happen.
While we wait for a revolution based on a better
understanding of cancer genetics, I would like to emphasize multiple significant
evolutionary changes which have taken place in the last forty years. When considered together, they have allowed
us to increase survival and in most cases, decrease pain and deformity:
Earlier
Detection
Early detection is the single most significant reason for
increased survival. In 1973, there was essentially no mammography, and what was
available was of poor quality. Patients presented with larger masses and more
involvement of lymph nodes, and as a result, survival rates were lower. With digital
mammography, and now tomosynthesis (3-D mammography), tiny cancers can be
detected. This allows for more surgical
options and increased survival. While a
recent Canadian study refutes that, in my view, that study is flawed, and also contradicts
the results of multiple other studies. If the quality of the mammogram is poor,
early cancers will be missed and the survival advantage of mammography is lost.
Another advance is that almost all breast biopsies can
now be done in an office with a needle rather than surgery. When I started practice, a breast biopsy
meant an operation under a general anesthetic with two nights in the hospital!
Increasing
Surgical Options
Forty years ago, the standard operation for cancer was
the Radical Mastectomy. The breast, underlying muscles, and many lymph nodes
were removed along with the overlying skin. A skin graft was frequently used,
making this surgery more painful, and extending the hospital stay. Because of
the extensive lymph node removal, arm swelling (lymphedema) was common. During
the 1970’s, the Modified Radical Mastectomy became the standard and is still
performed today. This procedure removes the breast but leaves more of the
overlying skin and all of the underlying muscle. By the 1980’s, surgeons began
doing Lumpectomies if the tumor was small enough and the patient preferred to
avoid a mastectomy. This procedure involves removing the lump and some normal
surrounding tissue and is followed by radiation.
There have been two other significant advances. One is
the Sentinel Node Biopsy, where dye is injected into the breast before and
during surgery. This demonstrates which underarm lymph nodes would most likely
have cancer. We remove those (usually
1-3 range) and if they are negative, we leave the remaining, presumably normal
nodes alone. This diminishes the chance of arm swelling if the nodes are
negative.
Another increasingly common operation is a unilateral or
bilateral Skin Sparing Mastectomy. Here, all of the breast tissue is removed
through a very small incision, occasionally even sparing the nipple. This is
followed by reconstruction of varying types, the excess skin allowing for
better cosmetic results. This is frequently chosen by women with a small
cancer, a large family history, prior worrisome biopsies, or a high risk of
cancer because they carry the BRCA gene mutation. The results with
reconstruction are usually excellent, and outcomes continue to improve.
More
Focused Radiation
When I trained, radiation was only used for large tumors
which were considered inoperable. Now it is a part of the local therapy in
lumpectomy cases. Radiation can be administered to the entire breast or just to
the area where the tumor existed (where the risk of recurrence is highest). In
terms of recurrence, both methods seem equally effective. Each has advantages and disadvantages. The
biggest change in radiation is the increased precision with which it is
delivered, thereby minimizing damage to adjacent normal tissues.
Focused
Drug Therapy
The field of medical oncology barely existed until 1970. There
were only two drugs for breast cancer, and no way to determine which was best
to use. There was no anti-estrogen therapy except removal of the ovaries. Since
then, there have been huge changes. A better understanding of cancer cells on
the molecular level has led to targeted therapy with the many new drugs. Some are effective against cells which are
stimulated by estrogen, and others are specific for a group of cancers (about
25%) which have overexpression of a specific growth factor. There have also
been advances to reduce the side effects of the drugs, but we still have plenty
of room for improvement. Modern chemotherapy has definitely improved survival
in breast cancer patients.
I’ve noticed that at cancer conferences, the medical
oncologist usually speaks last, following the surgeon. I think it’s because we
surgeons know that we’d better speak now, because as the genetic revolution
evolves, the field of medical oncology will render us obsolete. That day can’t
come soon enough.
For further inquiries about breast cancer management and
advancements, or HCA Virginia’s Breast Care Network, contact George A. Knaysi,
MD, of Richmond Surgical, at 804.285.9416, or visit their website at richmondsurg.com.
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