Breast cancer in young women: Pathologic features and molecular phenotype. (October 2016) - Sabiani, Laura
Abstract: 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 HER2 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; [HR]: 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. Highlights: Breast cancer in women under 40 years old represents 7% of breast cancers. The analysis of HER2 and hormone receptors status might identify subgroups. The outcome of young patients is worse in certain subgroups selected tumors. This classification could help to predict outcome and adjust systemic treatments.