The Latest on Sentinel Node Biopsy

For more than a century, when a woman had breast cancer, the surgeon would automatically remove all of her lymph nodes under the affected arm in order to catch any stray cancer cells that might have been trying to spread beyond the breast. Removing all these lymph nodes was of course believed to reduce the risk of more cancer, but the surgery also resulted in problems with the patient's arm mobility, and raised the risk that some women would develop lymphedema, a serious complication of breast-cancer surgery that can be even more debilitating and life changing than getting the breast cancer ever was.

The sentinel lymph node

But a decade ago, surgeons and scientists developed a technique that could pinpoint the specific lymph node that would be invaded first by any wandering cancer cells if they started to spread beyond the breast. This meant that rather than removing all of the nodes willy nilly, surgeons could now just remove this sentinel node, check it to see if it contained any breast-cancer cells, and, if not, leave all the remaining nodes intact. Now that sentinel node biopsy (as this procedure is called) has become the new standard of care, a woman's risk of debilitating and painful lymphedema has been greatly reduced.

If, on the other hand, the sentinel node does contain breast cancer, then a lymph-node dissection is of course performed to determine how many other nodes contain cancer. Knowing this information about the other nodes is important in determining the stage of the disease, as well as in identifying any additional treatment that may be needed after surgery. One treatment in particular that relies heavily on this information is radiation therapy to the armpit area.

But … there's one catch

Although sentinel node biopsy has simplified things immeasurably for both surgeons and patients, complications can still arise. This is because sometimes the sentinel node is neither chockfull of cancerous cells nor completely free of them. Quite often, only a few cancerous cells (known as micromets) are detected in the sentinel node, a finding that leaves surgeons in a quandary:  Should they remove and check more nodes? (Remember, the surgeons know from the get-go that each additional node they remove will increase the patient's chances of having severe problems later on.)

A review to help decide

Currently, an extensive review of the research literature on this topic is being undertaken at a national level--a review that is also taking into account numerous clinical databases and the opinions and experiences of many breast-cancer surgeons. The review will help determine what the standard of care should be regarding this question of micromets.

A new standard of care is suggested

A new research study was also completed last fall, and its results have led experts to strongly consider a new standard of care that would result in the following:

• If a woman is having a lumpectomy and she has a positive sentinel node, then no additional nodes would be removed, with the understanding that the radiation therapy that is nearly always done following lumpectomy surgery--including radiation to the armpit area--will be given without fail.
• If, however, the patient is undergoing mastectomy surgery and her sentinel node is positive, then an axillary-node dissection must be done. This is because a woman having a mastectomy is not automatically given radiation therapy as part of her treatment.

All this can be summed up by saying, if you are newly diagnosed, or you know someone else who is, please ask the surgeon-to-be these important questions before going under the knife:

• How many sentinel node biopsies have you performed, and what is your accuracy rate in finding the specific node called the sentinel node?
• If my sentinel node does turn out to be positive for cancer, will you be automatically performing an axillary-node dissection to remove more nodes at the same time?
• Is this decision dependent on whether I have a lumpectomy or mastectomy?
• How will you decide if additional nodes will need to be removed, and when will you make that decision? That is, would you base this decision on
  • the amount of cancer found inside the sentinel node?
  • Or on whether a lumpectomy or a mastectomy is performed?

Readers, you know the old saying about timing being everything? If you had been diagnosed 6 months ago, there would no longer be enough time to consider whether to have an axillary-node dissection or not.

As scientists and surgeons continue to discuss in which situations an axillary-node dissection would be appropriate, be sure that you are an informed patient so that you can have your voice heard and can participate in the decision-making to a reasonable degree.