Modified neoadjuvant clinicopathological risk stratification as a prognostic score in early and locally advanced triple-negative breast cancer

Background: Triple-negative subtype is an aggressive breast cancer with inferior survival. Pathological complete remission (pCR) is a good surrogate endpoint for survival among patients receiving neoadjuvant chemotherapy (NACT). We attempted to validate the clinical pathological score (CPS) with a modified risk grouping among Triple-negative breast cancer (TNBC) patients receiving NACT at our center.

Methodology: Data of patients with TNBC who underwent NACT between January 2014 to July 2017 were retrospectively analyzed. The composite CPS score included cTN stage and y pTN stage and ranged from 0 to 4. This was calculated using an available online software developed by MD Anderson Center. The score obtained from the calculator was used to develop a risk grouping into low risk (0, 1) and high risk (2, 3, 4). Invasive disease-free survival (iDFS) and locoregional recurrence-free survival (LRFS) were calculated using the Kaplan-Meier method.

Results: Seventy-eight patients with TNBC (median age: 45 [24-75]) had received NACT (anthracyclines and taxanes). Early and locally advanced breast cancer constituted 17 (21.8%) and 61 (78.2%), respectively, and 22 (28.2%) achieved pCR. After a median follow-up of 25 months (5-62), 3-year iDFS and OS were 59% and 81%, respectively, for the entire population. The 3-year iDFS in low-risk (n = 18) and high-risk (n = 60) patients was 85% and 51%, respectively (P = 0.03). The 3-year LRFS in low risk and high risk was 93% versus 58% (P = 0.03). The 3-year OS in the low and high risk was 93% and 77%, respectively (P = 0.24, NS).

Conclusion: Our study supports the use of the modified neoadjuvant clinicopathological score as a prognostic marker in patients with nonmetastatic triple-negative breast cancer. This needs to be validated in a larger subset of patients.