THE CELL-CYCLE INHIBITOR P27 IS AN INDEPENDENT PROGNOSTIC MARKER IN SMALL (T(1A,B)) INVASIVE BREAST CARCINOMAS

Breast carcinomas less than or equal to 1 cm in size (T-1a,T-b) are be ing detected more frequently as a result of screening, Because traditi onal prognostic parameters are either lacking (tumor size) or rare (no dal metastases), a marker(s) is needed to identify the subset of patie nts who could benefit from adjuvant therapy, A retrospective series of 202 patients with stage T-1a,T-b invasive breast carcinomas was evalu ated, The clinicopathological features (age, histological grade, exten sive in situ carcinoma, hormone receptor status, and nodal metastasis) as well as microvessel density and the expression of c-erb-B2, p53, M IB-1/Ki-67, and cdc25B were assessed. In addition, expression of the c ell cycle inhibitor p27 was evaluated. Nineteen patients (18% of patie nts who had axillary dissection) had locoregional lymph node metastase s, Forty-two % of them died of disease (median survival, 112 months), whereas mortality was 11% in nodenegative patients (median survival, 1 68 months; P = 0.0055), Patients with low p27 expression had a median survival of 139 months (17% mortality) versus 174 months (9% mortality ) in the group with high p27 expression (P = 0.0233), Lack of p27 was associated with poor prognosis when node-positive patients were exclud ed (P = 0.0252), Nodal status and low p27 were found to be the only in dependent prognostic parameters by both univariate and multivariate an alysis, with relative risks of dying of disease of 4.9 (P = 0.001) and 3.4 (P = 0.0306), respectively, Assessment of p27, which yields progn ostic information in node-negative patients, could be useful to identi fy patients with small, invasive breast carcinomas who might benefit f rom adjuvant therapy.