Pathological assessment following pre-operative systemic therapy

There are several specialized pathological evaluation algorithms available to sub-classify response to chemotherapy ranging from simple to complex that provide prognostic survival information. Currently, pathological complete response (pCR) is used as a surrogate marker of overall survival and overall disease-free survival, but pCR does not uniformly predict excellent overall survival. We would like to move away from a binary system of evaluating pathological response to a drug regimen of pCR versus non-pCR so that we identify subtle but potentially significant differences between drug regimens. Following treatment, hormone receptor status and HER2/neu status can change, and repeat hormone receptor studies should be performed on residual disease because changes will impact patient treatment and survival. The traditional prognostic factors of tumor grade and hormone receptor status pre-treatment also contribute to overall survival and disease-free survival in patients with and without a pCR.