According to Aramcki et al. [43], PDAC patients with isolated pulmonary metastasis are a distinct clinical and genetic subgroup, and tumors with lung metastasis display a significantly lower protein kinase D1 expression, which induces an increase in the secretion of small extracellular vesicles from cancer cells in PDAC compared with patients with liver metastasis. This evidence concerns the gene PRKD1 and metastasis.