Abstract PS6-23: Comparison between the American joint committee on cancer (AJCC) anatomic and prognostic stages for breast cancer

Abstract

Abstract Introduction: The knowledge regarding the tumor biology of breast cancer has grown substantially and resulted in the identification of different breast cancer subtypes based on their molecular profile, which led to an important change in treatment, it went from standardized therapy for personalized therapy. A panel of experts and representatives from AJCC were responsible for preparing the newest Cancer Staging Manual. The panel recognized the clinical usefulness of biological factors such as histological grade, expression of hormone receptors - HR (estrogen and progesterone) and overexpression and / or amplification of the human epidermal growth factor 2 (HER2) receptor in predicting patient survival and incorporated data regarding these biomarkers in the new staging system. In addition, for eligible cases, the ‘Recurrence score’ was also incorporated, a score generated by the analysis of OncotypeDx (genomic test). The new manual, therefore, started to use 3 stays. Anatomical staging - based on the classic TNM; the clinical prognostic staging and pathological prognosis staging - TNM association with the prognostic biomarkers (using clinical data in the first and data after surgical treatment in the second). Objective: To verify the concordance between anatomical staging from the 7th edition of the AJCC manual and the prognosis from its 8th edition in a cohort of patients with breast cancer at the Hospital do Servidor Público Estadual de São Paulo. Methodology: Observational and cross-sectional study, which evaluated patients undergoing surgical treatment at Hospital do Servidor Público Estadual from March 2014 to March 2019. Information was collected regarding age, menopausal status, tumor characteristics, anatomical and clinical staging, neoadjuvant chemotherapy, adjuvant chemotherapy and radiotherapy and type of surgery performed. The patients were staged using the digital platform “TNM8 Breast Cancer Calculator”. Results: 805 patients were included in the analysis. All patients were female, aged between 29 and 97 years, mostly in the post-menopausal period (78.88%). 74.04% of the cases were positive for ER, 66.21% positive PR and 88.07% HER2 negative. Prognostic staging downgraded a total of 285 out of 805 patients (35.4%). Almost all of the cases that decreased in staging were ER and / or PR + (283 of 285). Most of those who went up were Triple Negatives (100 out of 111). Conclusion: Prognostic Staging changes staging in almost half of the cases and there was a greater number of staging decreases in total and an association of increased staging with tumors considered to have a worse prognosis, which is in agreement with several studies already carried out since the launch of the new manual. Table 1. Changes in the staging groups. Anatomical Staging vs. Prognostic StagingAnatomical Staging (%)StageIAIBIIAIIBIIIAIIIBIIICIVPrognostic Staging (%)IA2486972Total that decreased staging285 (35,4%)IB21472619IIA602727IIB22294IIIA34297IIIB17122014IIIC14226IV4Total staging that increased 111(13,8%)Total unchanged 409 (50,8%) Table 2. Relationship of the immunohistochemical profile and change of stagingBiomarkersTotal (%)DifferenceTotalHR + / HER2 -575 (71,42%)-196 (16,70%)-2140 (24,34%)-321 (3,65%)0308 (53,57%)+110 (1,74%)HR + / HER2 +49 (6,09%)-19 (18,37%)-217 (34,69%)022 (44,90%)+11 (2,04%)HR - / HER2 +47 (5,84%)-12 (4,3%)045 (95,7%)HR - / HER2 -134 (16,65%)034 (25,4%)+169 (51,5%)+231 (23,1%)805 (100%) Citation Format: Mariana Soares Cardoso, Marcelo Antonini, Odair Ferraro, Matheus de Paula Solino, Samira Marcondes Cabral, Raissa Naiara Alves de Barros Vasconcelos. Comparison between the American joint committee on cancer (AJCC) anatomic and prognostic stages for breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS6-23.