GALNT9 and small cell lung carcinoma: Despite the distinct anatomical origins and histopathological divergence among various NE cancers, GALNT9‐mediated ANXA2 O‐GalNAc acts as a pan‐cancer mechanism to trigger MBL complement activation, coagulation, and thrombus formation, thus promoting liver metastasis of NE malignancies, including NEPC, SCLC, and neuroendocrine colon cancer.