Association of clinical biomarkers and response to neoadjuvant therapy in breast cancer

Neoadjuvant therapy is an essential component of multimodality therapy for locally advanced breast adenocarcinoma (BC). Complete pathologic response (pCR) is a useful surrogate for long-term oncologic outcome.

To assess the association between clinicopathologic, molecular and immunological markers and treatment response to neoadjuvant therapy in BC.

BC patients undergoing neoadjuvant therapy were identified from a prospectively maintained institutional database. Serum haematological/biochemical values, histopathologic, immunohistochemical data and TNM stage were obtained from electronic records. Patients were categorised into complete responders vs non-complete responders and responders vs non-responders. Statistical analysis was performed via SPSS.

Overall, 299 BC patients were included. The average age was 49.8 ± 11.5 years. A pCR was evident in 22.6% (n = 69). pCR was associated with early T stage and non-luminal subtypes (HER2 enriched [HER2 +] and triple negative [TNBC]). The neutrophil-lymphocyte ratio (NLR) pre-operatively was lower in patients with a pCR (p = 0.02). The lymphocyte-CRP ratio (LCR) was also slightly reduced in responders (p = 0.049) at diagnosis. A pre-op NLR greater than 2 was not found to be a significant predictive factor (p = 0.071) on multivariable logistic regression analysis. T stage at diagnosis (p = 0.024), N stage (p = 0.001) and breast cancer subtype (p = 0.0001) were also determined to be significant predictive factors of complete response.

pCR was more likely in patients with less advanced disease in BC. The presence of HER2 + or TNBC in BC also increases the likelihood of pCR. Neoadjuvant therapy stimulates the systemic inflammatory response; however, a reduced baseline NLR may be associated with increased pCR. Confirmation with larger datasets is required.