Breast cancer in young women: Pathologic features and molecular phenotype

Purpose: Controversy exists about the prognosis of breast cancer in young women. Our objective was to describe clinicopathological and prognostic features to improve adjuvant treatment indications. Methods: We conducted a retrospective multi centre study including fifteen French hospitals. Disease free survival's data, clinical and pathological criteria were collected. Results: 5815 patients were included, 15.6% of them where between 35 and 40 years old and 8.7% below 35. In 94% of the cases, a palpable masse was found in patients <= 35 years old. Triple negative and HERZ tumors were predominantly found in patients <= 35 (22.2% and 22.1%, p < 0.01). A young age <= 40 years (p < 0.001; hazard ratio [HR]: 2.05; 95% confidence limit [CL]: 1.60-2.63) or <= 35 years (p < 0.001; [HRI: 3.86; 95% [CL]: 2.69-5.53) impacted on the indication of chemotherapy. Age <= 35 (p < 0.001; [HR]: 2.01; 95% [CL]: 1.36-2.95) was a significantly negative factor on disease-free survival. Chemotherapy (p < 0.006; [HR]: 0.6; 95% [CL]: 0.40-0.86) and positive hormone receptor status (p < 0.001; [HR]: 0.6; 95% [CL]: 0.54-0.79) appeared to be protector factors. Patients under 36, had a significantly higher rate of local recurrence and distant metastasis compared to patients >35-40 (21.5 vs. 15.4% and 21.8 vs. 12.6%, p < 0.01). Conclusion: Young women present a different distribution of molecular phenotypes with more luminal B and triple negative tumors with a higher grade and more lymph node involvement. A young age, must be taken as a pejorative prognostic factor and must play a part in indication of adjuvant therapy. (C) 2016 Elsevier Ltd. All rights reserved.