Abstract P6-02-11: The TILs-US scores based on ultrasonography can predict lymphocyte-predominant breast cancer before surgery

Abstract

Abstract [Purpose] Tumor-infiltrating lymphocytes (TILs) has been shown to be useful for predicting outcomes after surgery in breast cancer, and while TILs can be evaluated in preoperative biopsy tissue, heterogeneous distribution of TILs requires examination of all biopsied tissue samples. We gave scores to preoperative ultrasonography (US) images with characteristics indicative of lymphocyte-predominant breast cancer (LPBC) and attempted to apply these for diagnostic prediction of LPBC. In this study, TILs-US scores based on preoperative US were assessed for their usefulness in predicting LPBC, the diagnosis of which was confirmed with postoperative pathology. [Methods] We evaluated 161 patients with invasive breast cancer between January 2014 and December 2017. All patients were treated by either mastectomy or breast-conserving surgery. Stromal lymphocytes were evaluated on preoperative biopsy tissues and surgical pathological specimens. Breast cancer samples with ≥ 50% stromal TILs were defined as pre-LPBC (preoperative biopsy tissues) and LPBC (surgical pathological specimens). TILs-US score was calculated from US before curative surgery. Based on clinicopathological factors including TILs-US scores based on preoperative US and pre-LPBC indicators, determinants useful for prediction of LPBC were examined. [Results] There were 39 cases of LPBCs and 122 cases of non-LPBCs in surgical pathological specimens. We set TILs-US score cut-offs for predicting LPBC at 4 points based on the receiver operating characteristics (ROC) curves (AUC, 0.88). There were significant predictors for LPBC in maltivariate logistic analysis (TILs-US score: OR26.8, p<0.001; pre- LPBC: 18.6, p=0.002; HER-2: OR9.2, p=0.009) in preoperative clinicopathological factor. The sensitivity, specificity and accuracy of TILs-US score for predicting LPBC were 0.74 (0.62-0.84), 0.89 (0.85-0.92) and 0.85 (0.79-0.90). Those of pre-LPBC were 0.51(0.42-0.55), 0.98 (0.96-1.00) and 0.87 (0.82-0.89), and those of HER2 were 0.28(0.19-0.36), 0.94(0.91-0.97) and 0.78 (0.74-0.82), respectively. The sensitivity of TILs-US score for predicting LPBC was significantly greater than those of pre- LPBC (p=0.04) and HER2 (p<0.001). On the other hand, the specificity of pre- LPBC for predicting LPBC was significantly greater than that of TILs-US score(p=0.002). The sensitivity, specificity and accuracy of predicting LPBCPerformance measureTILs-US score (95%CI)Preoperative biopsyHER-2P, TILs-US score vs. Preoperative biopsyP, TILs-USscore vs. HER-2Sensitivity0.74 (0.62-0.84)0.51 (0.42-0.55)0.28 (0.19-0.36)0.04<0.001Specificity0.89 (0.85-0.92)0.98 (0.96-1.00)0.94 (0.91-0.97)0.0020.11Accuracy0.85 (0.79-0.90)0.87 (0.82-0.89)0.78 (0.74-0.82)0.230.11 [Conclusions] TILs-US scores are an important factor that can predict LPBC preoperatively. The TILs-US score has particularly high sensitivity and may be an applicable index in the preoperative evaluation for LPBC. Citation Format: Kanou A, Masumoto N, Shiroma N, Fukui K, Sasada S, Emi A, Kadoya T, Yokozaki M, Arihiro K, Okada M. The TILs-US scores based on ultrasonography can predict lymphocyte-predominant breast cancer before surgery [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-02-11.