Abstract P6-07-35: Dragonfly Effect or Ironic Paradox: Prognostic Implication of Postsurgical Drain in Breast Cancer Patients

Abstract

Abstract Background: Surgical removal of primary breast cancer may result in subsequent alterations of host milieu. Massive clinical data have indicated that surgical extirpation favorably modifies the natural history for some patients, but it may also precipitate the metastatic outgrowth for others. Drainage fluid, harvested from a post-surgical wound, appears to be a physiological response to surgical trauma. However, few clinicians have recognized that the volume of wound drain might mirror the postoperative recurrence kinetics. Methods: A total of 1439 patients were selected retrospectively from a large database of patients who underwent surgery between Jan 1, 2000 and Dec 31, 2002 in Fudan University Shanghai Cancer Center, Shanghai, China. The Spearman rank correlation analysis was conducted to evaluate the association between drainage volume of postoperative day 1 (POD1) and clinicopathological parameters, which included age at diagnosis, body weight at diagnosis, total number of excised axillary lymph nodes (ALNs), time to drainage volume less than 30ml (TTV30), total protein and albumin concentrations in serum. Survival curves were performed with Kaplan–Meier method and annual recurrence hazard was estimated by hazard function. Results: Drainage volume of POD1 was positively correlated with age at diagnosis (Spearman's P < 0.001), weight at diagnosis (P <0 .001) and number of excised ALNs (P <0 .001) and TTV30 (P <0 .001), whereas it was inversely correlated with total protein concentration in serum (p = 0.028). We also observed that drainage volume of POD1 was significantly higher in patients with larger tumors (P < 0.001) and ALNs involvement (P = 0.030). In the univariate survival analysis, there was less recurrence and death in patients with lower drainage volume of POD1 (both p = 0.006). Cox proportional hazards regression analysis revealed that drainage volume of POD1 was an independent predictor of recurrence-free survival (RFS; p = 0.035) and overall survival (OS; p = 0.047). Additionally, triple negative patients with larger volume of POD1 seemed to have poorer RFS (log-rank p = 0.022; Cox model P < 0.05) and OS (log-rank p = 0.015; Cox model P < 0.05). Conclusions: Our study suggests that postsurgical drainage volume was strongly correlated with prognosis in breast cancer patients. The aim of this study was not only to enlighten novel prognostic factors, but also to infer that some host related characteristics such as extent of reaction to surgery play very important roles in the growth of micro-metastases. Therefore, integration of both host and tumor related factors be more precise to predict relapse risk than current modalities such as the St Gallen criteria, Oncotype-21 and Mammaprint etc. Further research on the underlying mechanism of this phenomena may lead the way to new adjuvant treatment targets and strategies. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-35.