Abstract PS2-02-16: Can NHS PREDICT Guide Oncotype DX Use in ER+/HER2− Early Breast Cancer: A Multicentre Analysis

Abstract Background: In early-stage estrogen receptor-positive (ER+), HER2-negative breast cancer, adjuvant chemotherapy decisions are increasingly guided by the Oncotype DX (ODX) Recurrence Score (RS). However, the high cost of ODX limits its use in resource-constrained settings. NHS PREDICT, a validated clinical prognostic tool, is often used to estimate survival benefit from adjuvant therapy. This study aimed to assess the correlation between NHS PREDICT estimates and ODX RS, to evaluate whether NHS PREDICT can help identify patients who would benefit most from ODX testing. Methodology: This multicentric retrospective study included 320 patients with early-stage ER+/HER2− breast cancer who underwent ODX testing between January 2012 and May 2025 across 3 tertiary cancer centers in India. The study was approved by the Institutional Ethics Committee (Waiver No. 2025/TMC/350/IRB7). NHS PREDICT scores were calculated using the online PREDICT tool. Chemotherapy recommendations based on NHS PREDICT were derived via multidisciplinary team (MDT) discussions, while final decisions were based on ODX RS. Clinical data were retrieved from REDCap databases and institutional electronic records. Statistical analysis was performed using SPSS version 25. Results: The mean age was 57.5 ± 10.2 years, mean tumor size 2.57 ± 1.15 cm, Ki-67 24.0 ± 17.6%, ODX RS 17.9 ± 10.8, and NHS PREDICT chemotherapy benefit score 3.29 ± 2.35%. A weak, non-significant correlation was observed between ODX RS and NHS PREDICT benefit score (Pearson r = 0.060, p = 0.285). Clinical risk and Recurrence Score (RS) were concordant in 55.9%. Concordance was highest in postmenopausal node-negative patients (72.5%) and lowest in postmenopausal node-positive patients (43.8%). RS upgraded 23.8% of clinically low-risk patients, highest in premenopausal node-negative cases (36.7%) and lowest in postmenopausal node-positive cases (2.8%). RS downgraded 79.8% of clinically high-risk patients, most notably in postmenopausal node-positive cases (84.1%). On a median follow-up of 29 months (IQR 24-33), there were 8 recurrences (4 local, 4 distant) and 6 deaths (2 cancer-related). The 5-year estimated distant disease-free survival was 96.5%, and cancer-specific survival was 98.9%. Conclusion: In this large multicentric Indian cohort, concordance between NHS PREDICT and RS for adjuvant chemotherapy decision-making was poor. NHS PREDICT frequently overestimated chemotherapy benefit, especially in postmenopausal node-positive patients, where 84% were downgraded by RS. Notably, in postmenopausal node-positive patients with low predicted benefit on NHS PREDICT, only 2.8% were upgraded by RS, suggesting that Oncotype DX testing may be safely omitted in this subgroup. These findings support a selective, cost-effective testing strategy in resource-limited settings Citation Format: S. K. Agrawal, M. Nadkarni, R. Ahmed, R. Sarin. Can NHS PREDICT Guide Oncotype DX Use in ER+/HER2− Early Breast Cancer: A Multicentre Analysis [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS2-02-16.