Pathology Characteristics that Optimize Outcome Prediction of T1N0M0 Breast Cancer

Introduction: A series of T1N0Mx breast cancer was analyzed to identify features that may predict outcome and influence treatment strategy. Methods: Data from 621 female patients with T1N0M0 breast carcinoma with a median follow-up of 7 years were analyzed. Results: The majority of the carcinomas were ductal type (78.9%). The greater part (52.7%) of primary lesion was classified as moderate grade (G2), while 20.9% as G1 and 14.8% G3. Peritumoral lymphatic/blood vessel invasion was detected in 81 (13%) tumorsThe strongest single feature influencing overall survival was LVI (p 0.0007). At multivariate analysis statistically significant prognostic features were also age 60 (p 0.008), premenopausal status (p 0.017), immunohistochemically detected positivity of estrogen hormone receptors (ER) (p 0.001), Mib1 (p 0.004) and BCL2 (p 0.050). Discussion: Identifying aggressive disease in T1N0M0 breast cancer would give valuable information for planning adjuvant therapy. Our analysis revealed that presence of LVI is the most reliable indicators of unfavourable outcome in T1N0M0 breast cancer. In addition, high Mib1 and BCL2 immunopositivity and low ER immunopositivity also have predictive value. The risk in women aged 60 years or younger was greater than that in women aged older than 60 years. No statistical difference was found between smaller and larger tumors (pT, p 0.46