When evaluating the relationship between gene expression of SMAα and PDGFRβ and tissue stiffness in the tumor stroma, Pearson correlation results showed a significant positive correlation between SMAα [r(28) = 0.706, p < 0.001] and PDGFRβ [r(28) = 0.809, p < 0.001] gene expression in the fibromuscular stroma and increasing tissue stiffness. This evidence concerns the gene PDGFRB and neoplasm.