Prognostic significance of peritumoral vessel invasion in clinical trials of adjuvant therapy for breast cancer with axillary lymph node metastasis

To assess the prognostic significance of peritumoral vessel invasion, data were examined for 1,510 women entered into the Ludwig Breast Cancer Group Trials I to IV evaluating adjuvant therapy for operable breast cancer with axillary nodal metastasis. Vessel invasion by tumor cells was identified by routine light microscopy in 59 per cent (889 of 1,510) of the patients and was equally distributed between premenopausal/perimenopausal (60 per cent, 468 of 778) and postmenopausal (58 per cent, 421 of 732) women. In logrank analyses stratified by nodal status (one to three or four or more positive nodes), the four-year disease-free survival (DFS) rate was significantly lower in patients with vessel invasion than in women without vessel invasion (50 per cent versus 65 per cent, P