TAC1 and colorectal cancer: Substance P and calcitonin gene-related peptide could represent useful diagnostic and prognostic biomarkers in colorectal cancer and, together with their receptors, neurokinin 1 receptor, and calcitonin receptor-like receptor, could represent potential therapeutic targets, but the limitations of this study must be taken into account—the small number of patients, the lack of heterogeneity of the patient group, and the relatively short follow-up period.