National practice patterns of sentinel lymph node dissection for breast carcinoma

Abstract
Background: The sentinel node is the first regional lymph node to receive tumor cells that metastasize through the lymphatic channel from a primary tumor. The tumor status of the sentinel node should reflect the tumor status of the entire regional node basin. Sentinel lymph node dissection (SLND) has recently been investigated for use in patients with early breast carcinoma to avoid the sequelae of complete axillary lymph node dissection (ALND). Published studies of SLND in breast cancer patients identify marked variations in technique, and there are few guidelines for credentialing surgeons to perform SLND. Study Design: The purpose of this study was to assess the current practice of SLND for breast cancer in the United States. A 27-item questionnaire was mailed to 1,000 randomly selected Fellows of the American College of Surgeons. Responses were anonymous. Statistical analysis was performed using SAS software (SAS Institute, Cary, NC). Results: Response rate was 41% (n = 410), and 77% of those who responded performed SLND for breast cancer. The majority (60%) of surgeons responding routinely ordered preoperative lymphoscintigraphy. Of those who did lymphoscintigraphy, 28% removed internal mammary lymph nodes when lymphoscintigraphy showed drainage to these nodes. Ninety percent of surgeons used both blue dye and radiocolloid. Eighty percent of centers responding performed routine immunohistochemistry on sentinel lymph nodes, and 15% performed reverse transcription polymerase chain reaction. Ninety-six percent of surgeons performed SLND for primary tumors 5 cm or smaller, and 95% performed SLND for an excisional cavity 6 cm and smaller. Twenty-eight percent performed SLND for high-grade ductal carcinoma in situ, and 28% of respondents performed 10 or fewer SLND procedures with subsequent ALND before performing SLND alone. Surgeons learned SLND through courses (35%), oncology fellowships (26%), observation of other surgeons (31%), or were self-taught (26%). Conclusions: The majority of surgeons in the United States use similar technique for SLND breast cancer. But, there was marked variation in the number of SLND cases validated by an ALND before performing SLND only.