ObjectiveTo compare the clinicopathologic characteristics and the difference of efficacy after neoadjuvant chemotherapy (NACT) between the patients with triple positive breast cancer (TPBC) and human epidermal growth factor receptor 2 (HER2) overexpression breast cancer. MethodsThe patients with TPBC and HER2 overexpression breast cancer admitted to the Affiliated Hospital of Southwest Medical University from January 2019 to July 2021 who met the inclusion conditions of this study were retrospectively collected, and the differences of clinicopathologic characteristics and the efficacy after NACT were compared between the patients with TPBC and HER2overexpression breast cancer. Meanwhile the risk factors affecting the efficacy of NACT were analyzed by logistic regression according to the risk factors of pCR based on the statistically significant indicators of univariate analysis and the indicators related to clinical characteristics. The HER2 overexpressing breast cancer was positive HER2, negative estrogen receptor (ER) and progesterone receptor (PR), and the TPBC was positive HER2, ER, and PR. The pathological complete response (pCR) was used to evaluate the efficacy, which was defined as ypT0/isypN0. ResultsA total of 105 patients were enrolled in this study, including 57 patients with TPBC and 48 patients with HER2 overexpression breast cancer, as well as 50 patients with pCR and 55 patients with non-pCR. ① Compared with patients with TPBC, the patients with HER2 overexpression breast cancer had the higher proportions of Miller-Payne system grade 4–5, partial response, pCR, and neutrophil-lymphocyte ratio (NLR) >2.77 (P<0.05). There were no statistical differences in other characteristics such as age, family history of breast cancer, histological grade, T and TNM stages, lymph node metastasis, lymphocyte-monocyte ratio, Ki-67 expression, and surgical method between them (P>0.05). ② The results of logistic multivariate analysis showed that the later T stage, the lower Ki-67 expression, the lower NLR, and the positive ER and PR statuses were not easy to achieve pCR after NACT (P<0.05). ConclusionsAccording to the results of this study, the efficacy of patients with HER2 overexpression breast cancer receiving NACT is more likely to achieve pCR than that of patients with TPBC. Positive hormone receptors (ER and PR), later T stage (stage 3–4), lower Ki-67 expression, and lower NLR (≤2.77) might be a worse efficacy after NACT for patients with breast cancer.