In the validation set, we found similar trends with poor DFS for STMN1 (HR = 2.786, 95% CI: 1.165–6.660, P = 0.021), phosphorylation at Ser25 (HR = 2.547, 95% CI: 1.037–6.253, P = 0.041) and phosphorylation at Ser38 (HR = 2.506, 95% CI: 1.050–5.981, P = 0.038), whereas phosphorylation at Ser16 (HR = 0.328, 95% CI: 0.128–0.840, P = 0.020) and Ser63 (HR = 0.372, 95% CI: 0.161–0.862, P = 0.021) were correlated with prolonged DFS in breast cancer patients. Here, STMN1 is linked to breast carcinoma.