Factors correlating with lymph node metastases in patients with T1 breast cancer

Background: Identification of reliable predictors of axillary metastases (A LNM) may be useful in selecting appropriate management for patients with T1 -size breast cancer. This study was undertaken to determine the degree of c orrelation between ALNM and several variables, including age, race, menopau sal status, palpability, tumor size, positive margin on initial excision, h istology, grade, lymphatic invasion (LI), estrogen receptor status (ER), pr ogesterone receptor status, S-phase, and ploidy. Methods: Data from 1416 patients with T1 breast cancers treated at Columbia -Presbyterian Medical Center between 1989 and 1998 was reviewed. Patients w ith multifocal tumors were excluded. Results: Mean patient age was 57.5 years (SD = 12.0); 65% of the patients w ere postmenopausal. One hundred thirty-one patients with T1a (less than or equal to0.5 cm), 435 with T1b (0.6-1.0 cm), and 850 patients with Tie (1.1- 2.0 cm) lesions were studied. The overall rate of ALNM was 23%. AM was iden tified in 11% of T1a, 15% of T1b, and 29% of T1c patients. Statistically si gnificant factors from univariate analysis were age, palpability, skin chan ges, tumor size, LI, histology, grade, ER status, and positive margin on in itial excision. Conclusions: Axillary staging by either sentinel lymph node biopsy or level I/II axillary dissection is indicated for most T1 breast cancer patients. Omission of axillary staging can be considered for highly selected patients with T1a cancers.