WASHINGTONSurgeons in community hospitals as well as
in university-based cancer centers can successfully find sentinel lymph nodes
(SLNs) in breast cancer patients for biopsy,
Douglas S. Reintgen, MD, of the H. Lee Moffitt Cancer Center, University of
South Florida, Tampa, said at the 54th Annual Cancer Symposium of the Society
of Surgical Oncology (SSO).
Reporting final results from the Department of Defense
Multi-Center Breast Lymphatic Mapping Trial, he said that the procedure has
"the potential for being standard of care" for nodal staging in
Axillary lymph node status is the most powerful predictor of
outcome in breast cancer, he observed. The multi-institution study aimed to
determine how successfully surgeons in a variety of settings could find SLNs
and also how commonly skip metastasessituations in which a sentinel node is
negative but other axillary nodes are positiveoccurred in patients with
invasive breast cancer.
The mapping technique used in the study included both blue dye
and a ra-diocolloid. In addition, the trial evaluated the utility of
preoperative lymphoscin-tigraphy for mapping lymph nodes.
The study included 111 surgeons at 42 institutions, 71% of
which were community hospitals. The trial involved 965 women with invasive
breast cancer, 64% of whom underwent lumpectomy. Most had small, infiltrating,
ductile tumors. Accrual began in July 1997 and lasted through January 1999.
Participating surgeons who were unfamiliar with lymphatic
mapping using blue dye and radiocolloid took a formal course in the procedure.
Each of these surgeons followed the study’s protocol I for the first 30
cases; for these patients, complete axillary lymph node dissection followed SLN
mapping and SLN biopsy. All nodes excised underwent routine
histologic examination for metastatic
Once a surgeon had completed 30
cases and entered protocol II, complete axillary lymph node dissection was
performed only when metastatic disease was found in a sentinel lymph node.
Positive nodes were found in 114 protocol I patients. Five of
these women had a positive node despite a negative SLN, resulting in a skip
metastasis rate of 4%. Preoperative lympho-scintigraphy revealed that 13% of
the patients had extra-axillary drainage.
Surgeons successfully found a sentinel lymph node 86% of the
time. Surgeons at Moffitt succeeded more often, 93% of the time, because of
their extensive experience doing lymphatic mapping in breast cancer. The
surgeons at the other institutions had a combined average 85% success rate at
Increased experience with the technique improved surgeons’
results, Dr. Reintgen observed, noting that, "as people got through their
learning curve, they did better."
Because the success rates of surgeons at community hospitals
did not differ significantly from those at university medical centers, the
technique has the potential to "change the staging system for breast
cancer, as it did for melanoma, and the standard of care for the surgical
treatment of the disease," he said.