The Perfect Pathology Report After Neoadjuvant Therapy

Abstract

Neoadjuvant therapy is increasingly being used in the management of breast cancer patients and, since comprehensive specimen handling and precise histological reporting is essential to assess the degree of response to therapy, histopathologists are acknowledged to play a key role in this multidisciplinary setting. However, as a matter of fact, only minimal guidelines for specimen handling are on record. This means that in every day routine practice it is not uncommon for oncologists to deal with pathology reports where important parameters are missing (such as formal comments about therapy response). According to the latest American Joint Committee on Cancer (AJCC) staging classification, posttreatment size of residual disease (ypT) should be estimated based on the best combination of imaging, gross and microscopic histological findings. Therefore, pathologists should ideally be provided with clinical and radiological information before proceeding with careful grossing. During the cut-up, large sections or extensive mapping of samples submitted to microscopic evaluation should be carried out to reconstruct the disease extent: this is particularly crucial when the lesion is unapparent both at imaging and at macroscopic observation. Histopathological reports cannot preclude from mandatory information about the presence of residual invasive carcinoma, such as histotyping, staging (ypTNM), reevaluation of prognostic and predictive factors, and categorization of degree of response according to dedicated classification systems (performed by comparing pretreatment biopsies with surgical specimens). In this review we will analyze the critical issues in such an assessment and we will provide a pragmatic approach with the intent to aim at the "perfect" pathology report.