Colorectal Cancer: A Brief and Simplified Analysis of a Complex Disease

<i>Background and Objectives:</i> This study examined factors influencing the onset and progression of colorectal tumors, including patients' epidemiological data, tumor location (right-sided, left-sided, and rectal), histomorphology, perineural or intraneural invasion, lymph node status, immune reactions, mismatch repair (MMR) status, and commonly observed mutations. Our primary goal was to evaluate their predictive and prognostic value and interactions. <i>Materials and Methods:</i> We analyzed a retrospective cohort of 100 patients with colorectal adenocarcinoma diagnosed between 2020 and 2023, using formalin-fixed paraffin-embedded (FFPE) tumor blocks. The methods included routine H&E microscopy, immunohistochemistry, Next-Generation Sequencing (NGS), and subsequent statistical analysis. <i>Results:</i> The findings showed a median diagnosis age of 70 years, with no gender-specific tumor localization. Right-sided tumors were prevalent, especially among patients with a defective MMR (dMMR), which represented 89% of dMMR cases. MMR status significantly correlated with tumor localization. We observed significant relationships between tumor grade, lymphovascular invasion, and overall tumor stage. Higher tumor grades and stages correlated with increased lymphovascular invasion and lymph node involvement. Interestingly, tumor budding did not correlate with lymph node metastasis but was significantly associated with higher tumor grades. Most BRAF mutations were found in right-sided tumors, indicating a significant correlation with this localization. <i>Conclusions:</i> This study focuses on the diversity of colorectal cancer (CRC) by examining how genetic and histological characteristics vary based on tumor location or other tumor variables.