Gastrointestinal bleeding due to small bowel metastasis from lung adenocarcinoma: A case report

Figure 1 Oral small bowel imaging. A-C: Visible elevation of the small intestine and bowel occupation with hemorrhagic manifestations.

Figure 2 Immunohistochemistry results. A: CK7 is a key component of cytokeratin, and the positivity is usually indicative of a high likelihood of adenocarcinoma. In this patient, CK7 was distinctly positive in a localized area; B: The primary site of Ki67 positivity is located in the nucleus. Ki67 is a marker of cell proliferation and primarily reflects the proliferative state of the cell. The immunohistochemistry result of the small bowel microscopy pathology of this patient shows a Ki67 index of 65%, reflecting a high proliferative activity). CA weakly positive expression of SATB2 is observed in the individual; D: SMARCA4-deficient undifferentiated carcinomas are commonly found in multiple sites, most especially in the lungs and rarely in the gastrointestinal tract. Based on a 2023 lung tissue biopsy that also demonstrated SMARCA4 deletion, intestinal metastases from lung cancer cannot be excluded from this intestinal tissue; E: Weak, localized positivity for Villin was observed.