Metastatic cancer remains a leading cause of cancer-related mortality, with a 5-year survival rate of just 8% for pancreatic ductal adenocarcinoma (PDAC). Among patients with metastatic PDAC, those with liver metastases experience significantly worse outcomes compared to the rare cases of isolated lung metastases. Recent findings by Link and colleagues reveal that these distinct metastatic patterns reflect underlying biological differences beyond established molecular subtypes. Specifically, the authors curated a primary organotropism (pORG) gene signature that is enriched in the liver cohorts. In detail they found that high-pORG/liver-avid tumors are characterized by high replication stress, enriched DNA repair pathways, and an immunosuppressive microenvironment, whereas low-pORG/lung-avid tumors display stronger immune infiltration, higher T cell density and reduce the richness of TCR repertoire, and better survival outcomes. These insights suggest that the clinical pattern of metastasis provides meaningful information about tumor biology and prognosis, complementing current subtype classifications in PDAC.
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