Abstract: Objective To analyze the clinical and pathological characteristics and prognosis of breast cancer in women aged 35 years and younger. Methods The clinical data of 105 breast cancer patients (≤35 years) who received comprehensive standardized treatment in our hospital in 2008 were retrospectively analyzed. And the clinical data of 103 breast cancer patients aged 65-70 years treated in our hospital during the same year were chosen as control group. Results During the follow- up period, local recurrence and metastasis were found in 25 patients (23.8% ), and dead in 17 cases (16.2%) in young group. In elderly group, local recurrence or metastasis were found in 8 patients (16.2%) and dead in 9 cases (8.7%). Compared with elderly group, the primary tumor diameter was large, the histological grade was high and the mutation rate of P53 was higher in the younger group (P < 0.05). The 5-year disease-free survival rate was lower in the young group than that of the elderly group (76.2% vs. 92.2% , Log- rank χ2=9.799， P=0.002). There was no significant difference in the 5-year overall survival rate between the two groups (83.8% vs. 91.3%, Log-rank χ2=2.758, P=0.097). Cox multivariate analysis showed that tumor diameter and axillary lymph node metastasis were independent prognostic factors influencing 5- year disease- free survival rate in young group. The positive expression of P53 and axillary lymph node metastasis were independent prognostic factors influencing 5-year overall survival rate in young group. Conclusion Our study indicates that the histological grade of breast cancer is higher and the prognosis is even worse in young patients. Therefore, young women with the high risk of breast cancer need to be targeted for prevention and screening strategies to develop individualized treatment programs.

Key words: breast neoplasms, prognosis, clinical and pathological features, young patient