Biopsy type does not influence sentinel lymph node status

Background This study sought to determine whether the type of biopsy examination independently affects sentinel lymph node (SLN) status in breast cancer patients. Methods A prospective multicenter study of patients who had SLN biopsy examination followed by axillary node dissection was analyzed to determine whether the type of biopsy examination influenced SLN status. Results Of the 3853 patients studied, 32% had a positive SLN. Patients were diagnosed by fine-needle (N = 293), core-needle (N = 2154), excisional (N = 1386), or incisional (N = 20) biopsy procedures. The rates of SLN positivity for these groups were 45%, 32%, 29%, and 65%, respectively (P < .001). Other factors predictive of SLN status included: patient age (P < .001), tumor size (P < .001), tumor palpability (P < .001), number of SLN removed (P < .001), type of surgery (mastectomy vs. lumpectomy) (P < .001), histologic subtype (P = .048), and the use of immunohistochemistry (P < .001). All of these factors remained significant in the multivariate model except for histologic subtype and biopsy examination type. Conclusions Biopsy examination type does not independently influence the risk for nodal metastasis.