S438 Clinical and Pathological Factors Associated With Advanced Stage Colorectal Cancer: A Cross-Sectional Study in Peru

Introduction: Colorectal cancer (CRC) is one of the most common and deadly neoplasms worldwide. According to GLOBOCAN 2022, there were over 1 million new cases globally, including 96,025 new cases and 53,585 deaths in Latin America. By 2040, the CRC burden is expected to increase by 63%. Approximately 1 in 5 patients present with metastasis at the time of diagnosis, increasing morbidity, mortality, and the economic burden on healthcare systems and families. This study aimed to identify clinicopathological factors associated with advanced-stage CRC, which could contribute to improving preventive and follow-up strategies. Methods: We conducted an observational, analytical, cross-sectional study including patients over 18 years old diagnosed with CRC at María Auxiliadora Hospital (Lima, Peru) between 2016 and 2020. The statistical power was 99.99%, based on the study by Mermut et al. Patients with autoimmune or infectious diseases were excluded. The dependent variable was stage IV CRC, confirmed by multidetector computed tomography (MDCT). Independent variables were selected based on a literature review. For multivariate analysis, Poisson regression with robust variance was used. Variables with P < 0.05 in the crude analysis were included in the adjusted model. Results: Of 116 CRC patients, 19 were excluded due to incomplete medical records. Nearly 20% were diagnosed at stage IV. Elevated platelet-to-lymphocyte ratio (PLR ≥192) was observed in 56.7%, and 44.3% had serum albumin <3.5 g/dL. Lymphovascular invasion was present in 55.7%, and perineural invasion in 32%. Poorly differentiated carcinoma was found in 19.6%, and carcinoembryonic antigen (CEA) ≥5 ng/mL in 53.6%. In the adjusted model, PLR ≥192 (aPR: 4.67; 95% confidence interval [CI]: 1.57–13.91), poorly differentiated CRC (aPR: 6.44; 95% CI: 2.42–17.15), CEA ≥5 ng/mL (aPR: 6.41; 95% CI: 2.16–19.03), and intestinal obstruction (aPR: 4.56; 95% CI: 1.90–10.98) were associated with an increased prevalence of stage IV CRC, while serum albumin ≥3.5 g/dL was a protective factor (aPR: 0.12; 95% CI: 0.02–0.87). Conclusion: Elevated PLR, poor histologic grade, high CEA levels, and intestinal obstruction were associated with stage IV CRC, whereas serum albumin ≥3.5 g/dL acted as a protective factor. Greater emphasis should be placed on evaluating complete blood count and albumin levels, as these are low-cost, accessible tools that can be implemented in primary care for CRC follow-up.