CRP and cancer: Accordingly, based on its origin, the etiology of CRP can be classified into three main categories: pain directly or indirectly caused by the cancer itself, which accounts for approximately 85% of cases; pain resulting from antineoplastic treatment, representing about 17% of cases; and pain caused by other concomitant disorders unrelated to cancer, comprising around 10% of cases [10,11,12,13] (Figure 1).