California Breast Cancer Research Program

The prognostic significance of LEA.135 expression, detected by immunohistochemistry in formalin-fixed and paraffin-embedded tissue sections, was evaluated and compared with the widely utilized clinicopathological parameters for patients with primary invasive breast carcinomas. Pathological parameters such as tumor size, histological tumor type, histological grade, nuclear grade, lymph node (LN) status, bone marrow (BM) status, as well as age of patient at initial diagnosis together with follow-up in years were available for this group of patients (n = 178). Among these parameters, tumor size, histological tumor type, histological grade, LN status, and BM status were individually and significantly associated with increased probability of recurrence by univariate analysis. By multivariate analysis, however, only tumor size, LN status, and BM status remained statistically significant. LEA.135-positive patients showed a statistically significant probability of not recurring (77 +/- 5% at 5 years after surgery) compared with patients who were LEA. 135-negative (49 +/- 6% at 5 years after surgery) (log-rank p < 0. 001). Furthermore, the association remained statistically significant by multivariate analysis (log-rank p = 0.019), demonstrating that LEA.135 expression independently and significantly identified breast cancer patients with favorable clinical outcome. In addition, there was a statistically significant association between loss of LEA.135 expression and poor prognosis when patients were stratified by pathological parameters. Furthermore, a subgroup of patients who were LEA. 135-positive/LN-negative experienced a decreased rate of recurrence compared with those who were LEA.135-negative/LN-negative (16% vs. 27%, respectively). A similar result was also obtained when BM-negative patients were stratified on the basis of LEA. 135-positive or LEA.135-negative subgroups for recurrence (18% vs. 43%, respectively). Most interestingly, the patients whose cancer cells were LEA.135-positive/LN-positive experienced a much lower rate of recurrence than those whose cells were LEA. 135-negative/LN-positive (29% vs. 57%, respectively). The results clearly demonstrate that LEA.135 expression was a significantly independent and favorable prognostic marker for patients with primary invasive breast carcinoma by both univariate and multivariate analyses.