Differences in Prevalence of Colorectal Carcinoma by Gender and Marital Status and Expression of DNA Mismatch Repair Proteins

Background: The effect of gender dimorphism and marital status on colorectal cancer mortality have been previously documented, but the relationship between these factors and DNA mismatch repair protein (MMRP) expression status is unknown. Methods: Colectomy specimens were reviewed retrospectively for patients between 2018 and 2023, with demographics including race/ethnicity, gender, marital status, faith, body mass index, pathologic staging, and MMRP expression status. Statistical analyses were performed by using baseline characteristics tables and various programs in the R package. Results: A total 1018 colectomies were reviewed, and the tumor stages were significantly higher in the right colon (stage 3 and 4) than in the left colon and rectosigmoid colon (p < 0.01). Marital status was significantly associated with patients’ gender, age, tumor size, and tumor stages (all p < 0.01). MMRP status was available in 775 cases, with 139 (17.9%) MMRP-deficient and 636 (82%) MMRP-proficient. MMRP deficiency was significantly associated with older female patients, larger tumor sizes, higher tumor stages, higher histologic grades, and was more common in the right colon (all p < 0.01). In addition, MMRP deficiency was statistically associated with a higher percentage of divorced and widowed patients (p < 0.01). Multivariate linear regression analysis revealed a persistent association of MMRP deficiency with tumor size, tumor grade, tumor stage, and nodal metastasis, but the associations with gender and marital status no longer existed. Conclusions: The differences in prevalence of CRC by gender and marital status and tumor MMRP status illustrate the importance of these factors on tumor stages and nodal metastasis but these associations are more complex with other confounding factors.