Comparison of Pathologic Response Evaluation Systems after Anthracycline with/without Taxane-Based Neoadjuvant Chemotherapy among Different Subtypes of Breast Cancers

• Published in: PloS one 2015-09, Vol.10 (9), p.e0137885-e0137885
• Main Authors: Lee, Hee Jin, Park, In Ah, Song, In Hye, Kim, Sung-Bae, Jung, Kyung Hae, Ahn, Jin-Hee, Ahn, Sei-Hyun, Kim, Hak Hee, Gong, Gyungyub
• Format: Article
• Language: English
• Subjects: Adjuvant chemotherapy; Adult; Anthracycline; Anthracyclines; Anthracyclines - administration & dosage; Anthracyclines - therapeutic use; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Biopsy; Breast cancer; Breast Neoplasms - classification; Breast Neoplasms - drug therapy; Breast Neoplasms - pathology; Bridged-Ring Compounds - administration & dosage; Bridged-Ring Compounds - therapeutic use; Cancer; Cancer therapies; Care and treatment; Chemotherapy; Chemotherapy, Adjuvant; Classification; Comparative analysis; Epidermal growth factor; ErbB-2 protein; Evaluation; Female; Gene expression; Humans; Kaplan-Meier Estimate; Lymphatic system; Medical research; Medicine; Middle Aged; Neoadjuvant Therapy; Neoplasm Staging; Neoplasm, Residual - pathology; Oncology; Outcome Assessment (Health Care) - methods; Pathology; Patients; Prognosis; Remission Induction; Reproducibility of Results; Retrospective Studies; Surgery; Survival; Survival analysis; System effectiveness; Systems analysis; Taxanes; Taxoids - administration & dosage; Taxoids - therapeutic use; Triple Negative Breast Neoplasms - drug therapy; Triple Negative Breast Neoplasms - pathology; Tumors
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0137885

Several methods are used to assess the pathologic response of breast cancer after neoadjuvant chemotherapy (NAC) to predict clinical outcome. However, the clinical utility of these systems for each molecular subtype of breast cancer is unclear. Therefore, we applied six pathologic response assessment systems to specific subtypes of breast cancer and compared the results. Five hundred and eighty eight breast cancer patients treated with anthracycline with/without taxane-based NAC were retrospectively analyzed, and the ypTNM stage, residual cancer burden (RCB), residual disease in breast and nodes (RDBN), tumor response ratio, Sataloff's classification, and Miller-Payne grading system were evaluated. The results obtained for each assessment system were analyzed in terms of patient survival. In triple-negative tumors, all systems were significantly associated with disease-free survival and Kaplan-Meier survival curves for disease-free survival were clearly separated by all assessment methods. For HR+/HER2- tumors, systems assessing the residual tumor (ypTNM stage, RCB, and RDBN) had prognostic significance. However, for HER2+ tumors, the association between patient survival and the pathologic response assessment results varied according to the system used, and none resulted in distinct Kaplan-Meier curves. Most of the currently available pathologic assessment systems used after anthracycline with/without taxane-based NAC effectively classified triple-negative breast cancers into groups showing different prognoses. The pathologic assessment systems evaluating residual tumors only also had prognostic significance in HR+/HER2- tumors. However, new assessment methods are required to effectively evaluate the pathologic response of HR+/HER2+ and HR-/HER2+ tumors to anthracycline with/without taxane-based NAC.