Usually a person with a new breast cancer diagnosis knows she has a decision regarding surgery: lumpectomy or mastectomy. Plenty of articles implore women and surgeons to avoid the bigger operation when possible, because mastectomy does not offer a survival advantage over lumpectomy. I have written previously about that choice.
One aspect of breast cancer surgery that’s less often discussed—about which patients may not be aware—is the method by which doctors check glands under the armpit. The old way to evaluate if cancer has spread is called axillary lymph node dissection. That procedure, in which surgeons remove as many glands as they can find in the armpit, carries significant risk of lymphedema, a sometimes painful arm swelling, and other complications.
The modern way to see if cancer has spread to nearby glands is called sentinel node biopsy. In this less drastic procedure, just a couple of lymph nodes are removed from the armpit. Taking a biopsy of “sentinel” nodes—selected after injection of labeling material, such as a dye or radioactive tracer, into the breast tumor—has been routine in many academic and cancer centers for over a decade, and is associated with lower rates of complications including lymphedema, and lower costs. It’s been at least 22 years since surgeons reported on this technique (in 1994).
Yet in only 60 to 80% of relevant breast cancer cases do surgeons perform only the lesser procedure, said Dr. Gary Lyman in a phone interview. He’s an oncologist and professor of public health at the University of Washington who co-directs the Hutchinson Institute for Cancer Outcomes Research in Seattle, and an author of updated ASCO guidelines published last month. The ASCO recommendations, like the American Society of Breast Surgeons consensus statement, support use of sentinel node biopsy in most cases of early-stage invasive breast cancer.
Full lymph node removal is an unfortunate and common example of breast cancer overtreatment, Lyman said. “Approximately two-thirds of women with early-stage breast cancer can safely undergo the sentinel node procedure without axillary node dissection,” he said. “If the sentinel node is negative, it was established years ago that a patient can skip the full axillary node dissection,” Lyman said. “Now we know that in most early-stage cases, even with a positive sentinel node, the dissection can be skipped,” he said. “There are caveats,” he indicated. (See this paper for details, and below.)
“The advantages of avoiding lymph node dissection are several,” Lyman said. “Quality of life is improved.” Chronic arm swelling is not nearly so frequent a complication of breast cancer surgery as it once was, he considered. “Surgeons have improved their skills. But it still happens.” The swelling can be problematic. “Women may be unhappy about the appearance of a swollen arm or hand. Some can no longer use their arm as before,” Lyman said. “It depends on what they do with their life, and for a living. If a woman types or if she’s a pianist, lymphedema is a big deal.”
Disparity in overtreatment is a significant concern, Lyman emphasized. Patients without insurance, with lower income, and who are less educated are more likely to have lymph node dissection, he said.
“Uptake in major cancer centers has been substantial, not perfect but very high,” he said. “Many patients are still treated in community settings,” he said. “Based on Medicare and other billing data, we know that’s where more surgeons still perform full axillary lymph node dissections,” he considered. “I feel strongly that most patients should be referred to a breast surgeon for this kind of surgery, ideally at a cancer center.”
“With sentinel node biopsy, the risks of developing infection or lymphedema go way down,” Lyman said. “Sentinel node biopsy lowers costs. There’s not a huge difference in operating room costs,” he noted. “But hospital stays are shorter, and problems with subsequent infections are reduced.”
Cynthia ("Cjay") Judge is a cancer survivor who advocates for people affected by lymphedema. At age 68, she lives in Las Vegas and co-hosts the Lymphedema Mavens podcast. “I experienced lymphedema over 30 years ago,” she told me by phone. “When I had my cancer surgery, no doctor even mentioned the possibility of lymphedema.”
Judge participates in several lymphedema support groups on Facebook and advocacy organizations including the National Lymphedema Network. “Every day I hear of people affected,” she said. “Some women have had it forever, living for lymphedema for years, and some don’t know that’s what it is until they hear about it from other patients,” Judge said. “Without proper care, they are really prone to cellulitis. People need to know about it before they have their surgery.”
“I’m a bit surprised that some doctors are not doing the sentinel node biopsy,” Judge said when we discussed the updated guidelines last month. “Actually, I’m stunned,” she continued. “There’s usually no reason to take out a gaggle of lymph nodes.”
“Women need to educate themselves before surgery, Judge said. Sentinel node biopsy still has risks, she considered. “It’s not foolproof. You can still get lymphedema, but the risk is lower,” she said. “If your doctor is not familiar with the procedure, you can get a second opinion or if at all possible, go elsewhere."
“There are doctors who say to me, I don’t know much about it,” Judge said. “That’s really sad. They should learn more about it, and follow the guidelines, because lymphedema is so devastating.”
The effectiveness and safety of sentinel node biopsy for breast cancer staging—as opposed to the larger, full axillary node dissection—is supported by careful studies over the past 20 years. In 2003, a randomized trial showed that sentinel node biopsy helpful, and not harmful, for women with tumors of less than 2 centimeters. By 2005, the American Society of Clinical Oncology (ASCO) issued guidelines deeming the sentinel node method an “appropriate initial alternative to routine staging” for early-stage breast cancer patients. A decade ago, the routine in many hospitals was for women to undergo sentinel node biopsy with intra-operative pathology evaluation of the sentinel node or nodes; if those results were negative, dissection would be stopped.
In 2011, a published JAMA trial showed that even when the sentinel node is positive, there is no survival benefit in full node dissection. The emerging “less-is-more” consensus was that the reason to do lymph node sampling is primarily for staging purposes—establishing prognosis and planning treatment—but that removing all the glands in early-stage cases doesn’t help and may cause net harm. But some doctors hesitated to adopt this recommendation. In 2014, ASCO published guidelines based on a literature review, quite similar to those updated last month.
Exceptions and areas of uncertainty include breast tumors of greater than 5 centimeters, inflammatory breast cancer, DCIS and some other circumstances. The recommendations to avoid axillary node dissection don’t apply to patients with advanced, stage 3 or 4, breast cancer.
An area of controversy pertains to neoadjuvant chemotherapy, Lyman said. That’s when patients receive chemotherapy before definitive surgery in an effort to shrink the tumor first. “This is an area of investigation.” Lyman referred to several preliminary papers on this subject presented at last month’s San Antonio Breast Cancer Symposium. “Historically we have recommended that the best results are doing the sentinel node before the chemotherapy.” But some patients or surgeons may prefer just one surgery, and so the sentinel node is checked only after patients receive some chemotherapy. “Neoadjuvant chemo can affect the lymph nodes. If they’re negative, that may give a false sense of security, that you don’t need to give hormonal or chemotherapy,” he said. “In this setting, the false negative rate will be higher. It’s a less meaningful finding. The patient needs be aware of that.”
The updated guidelines apply to many, many patients: In this year alone, over 150,000 U.S women will undergo surgery for early-stage invasive breast cancer. In most cases—when lumpectomy followed by radiation to the armpit is planned—axillary node dissection is no longer advised. This is the two-part question patients should ask their breast cancer surgeons: “Can you perform a sentinel lymph node biopsy, and avoid removing all of the glands from my armpit?”
