[Subareolar injection for sentinel lymph node biopsy in multiple breast cancer]

In this study we performed subdermal injection of 99mTc-labeled albumin combined with subareolar (SA) injection of blue dye to axillary lymphatic mapping and sentinel lymph node biopsy (SNLB) in patients with multifocal and multicentric breast cancer (MC) to evaluate the feasibility and accuracy of this technique. We compared the results with a group of patients with unifocal breast cancer. From January 1999 to March 2006 axillary lymph node mapping and SLNB was performed on 250 patients followed by a complete axillary lymph node dissection. Retrospective analysis showed that 32 (12.8%) of these patients have MC on final histopathologic examination and 218 (87.2%) have unifocal cancer. In statistical analysis tumor size shows a significant difference (p=.01) with largest lesions in MC. In MC often histological type is invasive lobular with or without in situ cancer (p= .001). Metastatic lymph node involvement was significantly higher in the MC group compared to unifocal cancer group (p=.001). False negative (FN) rate was 5.8% in MC and 9.6% in unifocal cancers. The overall accuracy of lymphatic mapping was 96.8% in MC and 97.6% in unifocal cancers. Sensitivity was 94.4% in MC and 91.2% in unifocal cancers. In this study we provide further evidence that lymphatic mapping may be reliable even in patients with MC. SA injection technique demonstrates a high sentinel lymph node identification rate and low FN rate; therefore this technique should been recommended to SLNB in patients with MC of the breast.