Learning Curves and Certification for Breast Cancer Lymphatic Mapping

Abstract

To determine the usefulness of lymphatic mapping and SLN biopsy, two distinct aspects of the technique must be evaluated, mapping success rates and mapping accuracy. The mapping success rate simply reflects the ability to successfully map a SLN. Mapping accuracy is reflected by the false-negative rate defined as the proportion of patients with axillary metastases among those in whom the SLN is negative for disease. It is critical within each institution that these two measurements be obtained to validate the multidisciplinary collaborative effort. It seems that surgeons with appropriate training should be able to map with 85% efficiency with zero or one false-negative cases in their first 10 patients with metastatic disease. It is our recommendation that individual surgeons join together and follow an institutional (IRB approved) protocol for lymphatic mapping in which each surgeon is required to perform at least 30 procedures of SLN biopsy followed by completion axillary lymph node dissections (phase I). There are several advantages for surgeons and patients to participate in national trials as a new technique is established: 1. Patients are fully informed. 2. For those patients who have SLN biopsy followed by a CLND (phase I), there is still an added advantage in that the SLN can be scrutinized more closely resulting in more accurate staging. 3. The surgeon and the institution can be reimbursed even while the surgeon is on the learning curve. 4. It provides for good publicity for the institution. The data should be reviewed for each surgeon after completing the first 30 cases. If the aforementioned goals of 85% success with one or fewer false-negative cases is achieved, then the individual surgeon may move on to a second (phase II) mapping protocol. In phase II, a SLN biopsy is performed and a CLND is performed only if a SLN cannot be located or the SLN contains metastases. Should the aforementioned criteria not be met, then additional procedures or onsite intraoperative mentoring may be required to further evaluate the deficiencies of the mapping procedure by the surgeon or institution. Remember that failure to map may be a function of surgical skill, nuclear medicine injection methodology, or the pathologic evaluation of the SLN. Should institutional problems arise, onsite mentoring may be helpful by someone with adequate mentoring skills to troubleshoot a potential problem. The previously outlined recommendations are similar to the recently published requirements of the American Society of Breast Surgeons that recommend documentation of 30 cases or more with an 85% or higher success rate in identifying a SLN and 5% or greater false-negative rate (single false-negative SLN in the series). A national network of training centers is being established for radioguided surgery. This new technology has the potential of being applicable to 350,000 new cases of cancer diagnosed annually in the United States. Applications include breast cancer, melanoma, and other skin tumors like Merkel cell carcinoma and poorly differentiated squamous cell carcinoma, parathyroid localization, vulvar and vaginal lesions, and bone localization. This network of training centers will provide an opportunity for surgeons, nuclear medicine physicians, and pathologists to come together and learn about this new technology. Training will include didactic sessions, live surgery, and hands-on experience with animal models. The faculty will consist of leading experts from across the country. Participating centers include the H. Lee Moffitt Cancer Center and Research Institute, John Wayne Cancer Institute, and the M.D. Anderson Cancer Center. Training sites will also be available in Durham, NC; Pittsburgh, PA; Seattle, WA; Little Rock, AR; and St. Louis, MO. The network provides access to a national lymphatic mapping database (http:/(/)mapping.rad.usf.edu), participation in national trials, and web site listings (melanoma.net, or breastdoctor.com, and endocrine