Risk Stratification of Early Breast Cancer (HR +/HER 2–) by CanAssist Breast and Its Corelation with Other Online Prognostic Tools: Experience from a Single Center

Abstract

Introduction Risk assessment by various methods for HR +/HER2– early-stage breast cancer (EBC) patients help clinicians stratify risk and tailor individual treatment. Multiple prognostic tests are available, both free and expensive. Free prognostic tools, the Nottingham Prognostic Index (NPI), and modified Adjuvant Online (mAOL) rely on clinical parameters. CanAssist Breast (CAB) considers both clinical parameters and tumor biology for assessing the risk of recurrence. Objectives The objective is to assess risk by CAB, NPI, and mAOL and discern the differences in the risk stratification in the EBC cohort of Bhagwan Mahaveer Cancer Hospital and Research Centre, Jaipur, Rajasthan, India. Methods Study cohort comprises 100 patients. Risk concordance was assessed by the kappa correlation coefficient and restratification analysis between risk groups of CAB, NPI, and mAOL was assessed using a two-sided p-value. Results Cohort was predominated by patients aged above 50, with T2/N0/G2 tumors. Low-risk (LR) and high-risk (HR) proportions by CAB, NPI, and mAOL were 67:33, 19:81, and 14:86, respectively. Across both age groups, CAB stratified more patients as LR compared with NPI and mAOL. In subgroups of patients with N0, G2, and T2 tumors, CAB identified significantly (p < 0.0001) higher (3–8 times) patients as LR than NPI and mAOL. In patients with T1/G1 tumors, risk proportions were similar by all three tools. Interestingly, CAB LR (57%) was four times that of NPI (14%) in the N1 subgroup. In G3 tumors CAB LR was 13%. mAOL failed to identify LR in the N1 and G3 subgroups and NPI in the G3 subgroup. There was poor agreement between CAB and NPI/mAOL (k 0.14 [95% confidence interval: 0.03–0.24]/0.11 [0.02–0.20]). Up to 11% of mAOL/NPI LR were detected as HR by CAB and up to 63% of mAOL and NPI HR as LR by CAB. Conclusion Prognostication by tools that use clinical parameters alone might be inadequate. Prognostication using CAB that integrates critical biomarkers indicative of tumor biology along with clinical parameters could be significant. The earlier published data on CAB across various ethnic cohorts and its comparable performance with Oncotype DX makes CAB a relevant prognostic test in HR +/HER2– EBC to make decisions on chemotherapy use.