Breast cancer surgery without drains: no influence on seroma formation.

It is not clear whether drains are necessary after breast cancer surgery. The purpose of this study was to compare seroma formation in patients that had postoperative drainage for 24 h with patients that had no drain after breast cancer surgery. In this retrospective cohort study 96 patients with a primary breast cancer were included. Between January 2009 and April 2011 44 patients had breast cancer surgery followed by postoperative drainage. Between May 2011 and February 2013 52 patients underwent breast cancer surgery without drainage. The operative procedures that were included were: axillary lymph node dissection, modified radical mastectomy or simple mastectomy±sentinel lymph node biopsy. There was no difference between both groups regarding frequency of seroma (84.6% versus 90.9%; p=0.290) and amount of seroma (540 ml versus 590 ml; p=0.446). Postoperative hospital stay was shorter in patients without drainage (2 versus 2.5 days; p=0.003). There was no difference between both groups in other secondary outcome measures. Modified radical mastectomy was an independent predictor of the amount of postoperative seroma (HR 0.039 [0.007-0.235]; p<0.001). These results suggest that there is no difference in seroma after breast cancer surgery between patients that had postoperative drainage and patients that had no postoperative drainage.