The effect of preferentially expressed antigen in melanoma (PRAME) expression status on survival in stage II and stage III colon cancer.

Purpose: There are no studies showing PRAME expression in stage II and III colon adenocarcinoma. In this study, we aimed to determine the frequency of PRAME expression and the relationship with survival and clinicopathological data in stage II and III colon adenocarcinoma that need adjuvant therapy.

Methods: Included were 81 patients with stage II and III colon cancer with adjuvant therapy without a second malignancy and systemic inflammatory diseases.

Results: A statistically significant relationship was detected between PRAME expression and disease progression and survival (p=0.01 and p=0.003, respectively). Shorter disease-free survival (DFS) and overall survival (OS) were detected in right colon tumors in patients with lymph node metastasis, metastatic lymph node >3, N1 or N2 according to the TNM staging system, with lymphovascular invasion, perineural invasion and PRAME expression (p=0.004, p=0.023, p=0.002, p=0.004, p=0.001, p=0.006, p=0.01, respectively and p=0.009, p=0.037, p=0.001, p=0.004, p=0.003, p=0.004, p=0.006, respectively). In multivariate analysis, it was determined that right colon tumor (HR: 0.488, 95% CI, 0.201-0.998, p=0.049) and PRAME expression (HR: 0.423, 95% CI, 0.170-1.052, p=0.046) were independent risk factors for short DFS. For the OS, only the presence of PRAME expression was determined as an independent risk factor. (HR:0.332, 95%CI, 0.129-0.856, p=0.022).

Conclusion: PRAME can be a potential target in immunotherapy in colon cancer treatment.