Abstract P3-08-35: Reassessment of traditional oncotype scoring using TAILORx criteria: A large institutional review

Abstract

Abstract Background. Oncotype Dx Recurrence Score (RS) is a 21-gene assay used to predict recurrence in early stage breast cancer and guide chemotherapy decisions. After the completion of the TAILORx trial in 2017, there were changes in the cutoffs for the risk categories and found that there was chemotherapy benefit for women age <50 and RS 16-25. The aim of this study was to re-categorize patients using the TAILORx cutoffs and reassess clinical outcome based on recurrence and metastasis.Materials and Methods. With IRB approval, the CoPath pathology database was queried for patients who were newly diagnosed with breast cancer from 2012 to 2017 and Oncotype scores. The original pathology report and chart was reviewed to assess treatment decisions, recurrences and/or metastasis and their follow-up. Patients with hormone receptor negative, HER2 positive or lymph node macrometastasis were excluded. The patient were re-categorized based on TAILORx cutoffs and subgroup analysis was performed based on age, RS, recurrences and metastasis.Results. There was a total of 620 patients. The mean age was 60.19 years (range, 25-81 years). The mean follow-up was 36.67 months (0-262 months). Forty-seven patients were added to the high-risk category based on the lower TAILORx cutoff (recurrence scores =26-30). An additional 56 patients were recommended chemotherapy based on RS 16-25 and age <50. Recurrence was present in 26/620 patients. The recurrence rate was higher in younger patients (age <50) (8% vs 3.4%, p=0.033) and also higher in patients who refused chemotherapy than the patients who received chemotherapy (13% vs 6%, p=0.013). The recurrence rate was lower in patients who received hormonal therapy (2.4% vs 5%, p=0.007). When the patients were stratified based on age and RS, younger patients who refused chemotherapy with higher RS (> 16) showed even higher recurrence than those who received chemotherapy (33% vs 6%). The older patients with higher RS (> 25) showed no significant difference for recurrence between the group who received chemotherapy and who did not receive/refuse chemotherapy. There was a total of 17/620 patients with metastasis. It was frequent in younger patients (age <50) and higher tumor grade (p=0.014 and 0.032, respectively). There was no significant difference for metastasis in patients who received or did not receive/refused chemotherapy. Interestingly, there were no metastasis in 11 old patients with higher RS >25) who refused chemotherapy. Conclusion. Based on the TAILORx trial recommendations, the number of patients receiving chemotherapy almost tripled in our cohort. The recurrence and metastatic rate were more frequent in younger patients. The recurrence rate was found to be higher in younger patients (RS >16) who refused chemotherapy and lower in patients who received hormonal therapy. There was no significant difference for metastasis in the groups who received chemotherapy or not. All of the older patients with higher RS who refused chemotherapy did not develop a local recurrence or metastasis. Age <50 and Recurrence rate based on cutoff for chemotherapyLow cutoff (RS<16) (p=0.009)High cutoff (RS> 16) (p=0.041)Chemotherapy RecurrenceNo recurrenceTotalRecurrenceNo RecurrenceTotalReceived 2 (50%)2 (50%)42 (6%)31 (94%)33Not received2 (5%)38 (95%)401 (4%)26 (96%)27Refused 0 (0%)2 (100%)22 (33%)4 (67%)6Total4 (9%)42 (91%)465 (8%)61 (92%)66Age >50 and Recurrence based on cutoff for chemotherapyLow cutoff (RS<25) (p=0.019)High cutoff (RS> 25) (p=0.256)Chemotherapy RecurrenceNo recurrenceTotalRecurrenceNo RecurrenceTotalReceived 2 (5%)36 (95%)382 (3%)55 (97%)57Not received 9 (3%)342 (97%)3511 (6%)15 (94%)16Refused 2 (17%)10 (83%)120 (0%)11 (100%)11Total1338840138184Age < 50 and Metastasis based on cutoff for chemotherapyLow cutoff (RS<16) (p=0.111)High cutoff (RS> 16) (p=0.605)Chemotherapy MetastasisNo metastasisTotalMetastasisNo MetastasisTotalReceived 1 (25%)3 (75%)42 (6%)29 (94%)31Not received 1 (3%)38 (97%)393 (11%)24 (89%)27Refused 0 (0%)2 (100%)20 (0%)6 (100%)6Total2434555964Age > 50 and Metastasis based on cutoff for chemotherapyLow cutoff (RS<25) (p=0.111)High cutoff (RS> 25) (p=0.118)Chemotherapy MetastasisNo metastasisTotalMetastasisNo metastasisTotalReceived 1 (3%)37 (97%)383 (5%)53 (95%)56Not received 4 (1%)344 (99%)3481 (6%)15 (94%)16Refused 1 (8%)11 (92%)120 (0%)11 (100%)11Total639239847983 Citation Format: Akisha Glasgow, Philip Bomiesl, Paula Silverman, Hannah Gilmore, Aparna Harbhajanka. Reassessment of traditional oncotype scoring using TAILORx criteria: A large institutional review [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-35.