Breast bets to fight the Big C

Today, there are many more options available to diagnose and treat breast cancer. Every year in the Philippines, thousands of women, and some men, too, are diagnosed with breast cancer. In recent years, our understanding of the nature of the disease has improved and the number of more precise diagnostic tests and effective treatments has increased. For one, doctors now know that breast cancer is not just one disease — there are several types, each with its own unique characteristics. As a result, doctors are able to diagnose more accurately and to treat more specifically the different types of breast cancer. Today’s article discusses the latest advances in breast cancer diagnosis and management.

New laboratory tests

There are two new laboratory tests that hold promise in being able to diagnose breast cancer more accurately:

• Gene expression studies. One of the dilemmas with early-stage breast cancer is that doctors cannot always accurately predict which women have a higher risk of cancer coming back after treatment. That is why almost every woman, except for those with small tumors, receives some sort of adjuvant therapy after surgery. To try to better pick out who will best benefit from adjuvant therapy, researchers have looked at many aspects of breast cancers. In recent years, scientists have been able to link certain patterns of genes with more aggressive cancers — those that tend to come back and spread to distant sites. Some tests, based on these findings, such as the Oncotype DX and MammaPrint tests, are already available, although doctors are still trying to determine the best way to use them.

• Circulating tumor cells. Researchers have found that in many women with breast cancer, cells may break away from the tumor and enter the blood. These circulating tumor cells can be detected with sensitive lab tests. These tests are not yet available for general use, but they may eventually be helpful in determining whether treatment (such as chemotherapy) is working in patients with metastatic breast cancer.

Newer imaging tests

Several newer imaging methods are now being studied for evaluating abnormalities that may turn out to be breast cancer.

• Scintimammography (molecular breast imaging). In scintimammography, a slightly radioactive tracer called technetium sestamibi is injected into a vein. The tracer attaches to breast cancer cells and is detected by a special camera. Current research is aimed at improving the technology and evaluating its use in specific situations, such as in dense breasts of younger women. Some early studies have suggested that it may be almost as accurate as more expensive magnetic resonance imaging (MRI) scans. This test, however, will not replace your usual screening mammogram.

• Tomosynthesis (3D mammography). This technology is basically an extension of a digital mammogram. The images taken can be combined into a three-dimensional picture. It may allow doctors to see problem areas more clearly, lowering the chance that the patient will need to be called back for more imaging tests. The role, however, of this technology in screening and diagnosis is still not clear.

• Computer-aided detection and diagnosis (CAD). This test was developed to help radiologists detect suspicious changes in mammograms. Computers help doctors identify abnormal areas on a mammogram by displaying the image on a video screen, with markers pointing to areas that the radiologists should check especially closely. Although some doctors find CAD helpful, the results of two large studies found that it did not find more cancers or find cancers earlier. It did, however, increase the number of women who needed to come back for more tests and/or have breast biopsies. Whether CAD will continue to be used in the future is still not clear.

Newer surgical techniques

Many types of breast cancers are first treated with surgery. Some women with breast cancer are diagnosed with early-stage disease. Studies show that their chances of survival are equally good whether they have a mastectomy (full removal of the breast) or a lumpectomy (removal of just the tumor) with some surrounding tissues (followed by radiation).

Sentinel node mapping helps doctors identify the first (or sentinel) lymph node to determine if breast cancer cells have spread. If the sentinel lymph node is cancer-free, chances are that other nearby lymph nodes are also unaffected and can be left in place. In the past, surgeons routinely cut out many lymph nodes in the underarm to find out whether the cancer had metastasized, or spread. But if it’s not necessary to remove those nodes, then women with breast cancer can avoid the possibility of developing lymphedema, a painful swelling of the arm. As a result of new research published in the past several years, routinely performing extensive axillary lymph node dissection is being reconsidered, and many women are now being spared this procedure if they have only one to three involved lymph nodes and are going to receive radiation (see illustration on Page D-1).

Another surgical procedure gaining ground is breast reconstruction. Some women who undergo mastectomy now choose to have reconstructive surgery as well, to restore the breast’s appearance. Surgeons can reconstruct breasts using implants, tissues from your own body, or a combination of both. Surgery is done in later stages or at the same time as the mastectomy, sparing women from seeing themselves without a breast. Technical advances in microvascular surgery (reattaching blood vessels) have made free-flap procedures an option for breast reconstruction. Most women who undergo breast reconstruction report improved psychological, social, and sexual well-being as well as satisfaction with the restored appearance of their breasts. This type of surgery, however, should be done only by those with special training on this procedure.

Newer radiation therapy technique

For women who need radiation after breast-conserving surgery, newer techniques such as hypofractionated radiation or accelerated partial breast irradiation may be as effective while offering a more convenient way to receive it (as opposed to the standard daily radiation treatment that take several weeks to complete). These techniques are being studied to see if they are as effective as standard radiation in helping prevent cancer recurrences.

New chemotherapy drugs

Advanced breast cancers are often hard to treat, so researchers are always looking for newer drugs. A drug class has been developed that targets cancers caused by BRCA mutations. This class of drugs is called PARP inhibitors and they have shown promise in clinical trials treating breast, ovarian, and prostate cancers that had spread and were resistant to other treatments. Further studies are being done to see if this drug can also help patients without BRCA mutations.

• Targeted therapies. These are a group of newer drugs that specifically take advantage of gene changes in cells that cause cancer.

• Drugs that target HER2: There are two drugs approved for use that target excess HER2 protein, trastuzumab and lapatinib. Studies are continuing to see which of these is best for treating early breast cancer. Other drugs that target HER2 protein are being tested in clinical trials, including TDM-1 and neratinib. Researchers are also looking at using a vaccine to target the HER2 protein.

• Anti-angiogenesis drugs. In order for cancers to grow, blood vessel must develop to nourish the cancer cells. Some studies have found that breast cancers surrounded by many new, small blood vessels are likely to be more aggressive. More research is needed to confirm this. Bevacizumab is an example of an anti-angiogenesis drug. Several other anti-angiogenesis drugs are being tested in clinical studies.

• Drugs that target EGFR. The epidermal growth factor receptor (EGFR) is another protein found in high amounts on the surfaces of some cancer cells. Some drugs that target EGFR, such as cetuximab and erlotimib, are already used to treat other types of cancers, while other anti-EGFR drugs are still considered experimental. Studies are now under way to see if these drugs might be effective against breast cancer.

• Other targeted drugs. Everolimus is a targeted therapy drug that was first approved to treat kidney cancer. In a recent study of post-menopausal women with advanced hormone receptor-positive breast cancer that had been previously treated with anastrazole or letrazole, giving everolimus with exemestane worked better than exemestane alone in stopping tumor growth. This led to its recent approval for use with exemestane for treating advanced hormone-receptor positive breast cancer in women who have gone through menopause. More studies using these drugs are planned.

Many other potential targets for new breast cancer drugs have been identified in recent years. Drugs based on these targets are now being studied, but most are still in the early stages of clinical trials.

Indeed, one can truly say that in the last few years, medical science has gained significant strides in its fight to beat this dreadful disease. In fact, breast cancer today doesn’t look that invincible any more than it was only a few years ago. Many scientists now feel that we have finally started to win the war against breast cancer.

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On another front, scientists are also gaining ground in another disease — HIV-AIDS. Don’t fail to read next month’s article entitled “The beginning of the end of AIDS?” which will appear in the November 6 issue of this paper.