Role of endocrine responsiveness and adjuvant therapy in very young women (below 35 years) with operable breast cancer and node negative disease.

Background: There is limited knowledge about prognosis, and treatment effects in young women with node-negative disease. Patients and Methods: We evaluated biological features, treatment recommendations and prognosis for 841 premenopausal patients with pT1-3, pN0 and M0, operated from 1997 to 2001. Results: Patients below 35 years (101, 12%) were more likely to have tumors > 2 cm (35.6% versus 24.2%, P = 0.002), grade 3 (48.5% versus 31.9%, P = 0.009) and with elevated Ki-67 expression (62.4% versus 50.7%, P = 0.002). At the multivariate analysis a statistically significant difference in disease-free survival (DFS, HR 4.44; 95% CI 2.53 to 7.78, P < 0.0001), risk of distant metastases (DDFS) (HR 3.23; 95% CI 1.32 to 7.94, P = 0.011) and overall survival (OS) (HR 2.89; 95% CI 1.06 to 7.87, P = 0.038) was observed for younger versus older patients and in the subgroup with endocrine responsive tumors (DFS, HR 5.17, 95% CI 2.72-9.83, P = < 0.0001; DDFS, 3.76, 95% CI 1.33-10.6, P = 0.013; OS, 4.71, 95% CI 1.09-20.4, P = 0.039). Conclusions: Compared with less young, very young patients with endocrine responsive and node-negative breast cancer have a worse prognosis. Tailored treatments should be explored in this cohort of patients.