PREDICTING AXILLARY NODE POSITIVITY IN PATIENTS WITH INVASIVE-CARCINOMA OF THE BREAST BY USING A COMBINATION OF T-CATEGORY AND PALPABILITY

BACKGROUND: In spite of the development of numerous new tumor markers, axillary lymph node status continues to be the single most important prognostic variable regarding survival of patients with carcinoma of t he breast. This study was undertaken to determine whether or not the c ombination of T category (TNM staging system) and palpability would be a better predictor of nodal positivity than T category alone. STUDY D ESIGN: Clinical and pathologic data were analyzed for 1,554 patients w ho underwent axillary lymph node dissection as part of their treatment for invasive carcinoma of the breast. Data were analyzed by the prima ry lesion's T category and whether or not the lesion was palpable. RES ULTS: Five hundred fifty-one (35 percent) of 1,554 axillary node disse ctions contained metastases. The probability of nodal involvement was significantly higher and the average tumor diameter was slightly, but significantly, larger for palpable Tlb, Tie, and T2 lesions when compa red with nonpalpable lesions within the same T category (all p values less than or equal to 0.003). The probability of lymphatic tumor embol i or vascular invasion was generally higher for palpable lesions compa red with nonpalpable lesions and increased as lesions got larger. The percentage of patients with low nuclear grade and favorable histology was generally lower for patients with palpable lesions compared with t hose having nonpalpable lesions and decreased as lesions got larger, C ONCLUSIONS: Nodal positivity was significantly higher for palpable Tlb , Tie, and T2 carcinoma of the breast when compared with nonpalpable c arcinoma of the breast within the same T category. The combination of T category and palpability was a more accurate predictor of nodal posi tivity than T category alone.