The impact of method of biopsy on the incidence of breast cancer sentinel lymph node metastases

BackgroundThe dislocation of the malignant cells along the needle tract during breast cancer (BC) diagnosis has been demonstrated by several studies. However, the published experiences that relate the diagnostic technique with sentinel node (SN) involvement are few and controversial. The aim of our analysis was to evaluate the impact of different techniques for preoperative BC biopsy among prognostic factors of metastases occurrence in SN.Materials and methodsWe reviewed the institutional clinical database of our Center. A total of 674 patients were diagnosed between February 1999 and December 2006 with invasive BC. SN metastases classification followed the 2002 American Joint Committee on Cancer (AJCC) TNM pathological staging: macrometastases, micrometastases, isolated tumor cells or negative. Only macrometastases and micrometastases were considered positive. Concerning fine-needle aspiration cytology, we used disposable needles of the size of 21–27 G. For percutaneous biopsy we used cutting needle type “tru-cut”; the Gauge needle ranged between 14 and 20.ResultsAt univariate analysis of specific parameters using positive SN as outcome, percutaneous diagnostic technique did not affect significantly the SN positivity (p = 0.60). At multivariate models only central quadrant lesion (p = 0.005) and lymph vascular invasion (LVI) presence (p < 0.0001) maintained the statistical significance as risk factor for positive SN status. Polytomic logistics models showed that only LVI maintained the statistical significance both for prediction of micrometastases and macrometastases.ConclusionsOur analysis showed that different techniques used for BC diagnosis did not influence SN status.