Introduction: Breast cancer represents a major public health concern in Cameroon, with over 70% of patients presenting at advanced stages. Neoadjuvant chemotherapy (NACT) has become a standard treatment for locally advanced breast cancer, with pathologic response serving as a potential surrogate marker for treatment efficacy. However, the factors influencing therapeutic response in sub-Saharan African populations remain poorly characterized. Understanding these determinants is crucial for optimizing treatment strategies in resource-limited settings. We sought to determine the therapeutic response to NACT and identify associated factors in breast cancer patients treated in Yaounde, Cameroon. Methods: We conducted a historical cohort study of non-metastatic breast cancer patients treated at Yaounde General Hospital and Yaounde Central Hospital from January 2019 to December 2023. Patients were categorized into good responders (pathologic complete response or >50% partial response) and poor responders (<50% partial response or no response) using Sataloff criteria. Clinical and pathologic responses were assessed using RECIST and Sataloff classification respectively. Bivariate correlation and ordinal logistic regression analyses were performed to identify factors associated with therapeutic response. Results: Among 119 female participants, good responders comprised 25.21% (pCR: 8.40%, pPR1: 16.81%) and poor responders 74.79% (pPR2: 68.91%, no response: 5.88%). Triple-negative breast cancer was the most common subtype (42.31%), with AC plus taxane being the most frequently used NACT protocol (53.78%). Clinical response showed 26.89% complete response and 57.98% partial response. Good responders had lower initial CA 15-3 levels compared to poor responders; however, this difference did not reach statistical significance (p = 0.24) and a higher proportion of negative surgical margins (83.33% versus 56.18%, p = 0.01). In multivariable analysis, histological grade (aOR = 2.39, 95% CI: 1.35 - 4.26, p < 0.001) and surgical margin status (aOR = 2.41, 95% CI: 1.22 - 4.76, p = 0.01) were independently associated with pathologic response. Conclusion: This study reveals a pathologic complete response rate of 8.40% in Cameroonian breast cancer patients, lower than rates in high-resource settings, likely reflecting limited access to targeted therapies and molecular testing. While good responders demonstrated favorable clinical characteristics including lower CA 15-3 levels, although this did not reach statistical significance and
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