Advances in predictive factors for pathological complete response after neoadjuvant therapy in locally advanced rectal cancer

For locally advanced rectal cancer (LARC), neoadjuvant chemoradiotherapy (nCRT) combined with total mesorectal excision has emerged as the standard therapeutic approach, as delineated in contemporary clinical guidelines. Pathological complete response (pCR) serves as a pivotal metric for assessing nCRT efficacy, with strong correlations to long-term survival outcomes and organ preservation strategies such as the "watch-and-wait" approach. However, inter-individual variability in treatment responses results in only approximately 20% of patients attaining pCR following nCRT. Accurate identification of these patients is imperative not only for optimizing therapeutic efficacy but also for substantially augmenting patient survival benefits. This article conducts a systematic review of domestic and international literature to synthesize the current research landscape regarding pCR predictive factors in LARC patients post-nCRT across five dimensions: patient-specific characteristics, tumor clinicopathological features, hematological markers, imaging modalities, molecular biomarkers, and multidimensional integrated predictive models. The review emphasizes the synergistic potential of integrating traditional clinical parameters with emerging radiomics, multi-omics biomarkers, and artificial intelligence algorithms. It seeks to furnish a theoretical foundation and reference framework for the development of personalized precision treatment strategies, optimization of therapeutic pathways, and maximization of organ preservation opportunities in clinical practice.