Bone marrow metastasis of gastric signet ring cell carcinoma complicated by thrombotic microangiopathy: A case report

Figure 1  Magnetic resonance imaging showing abnormal signals in the thoracic and lumbar vertebrae and pelvis.

Figure 2 HE staining of pathological sections of gastric biopsy tissue after endoscopy. A: 100 × magnification; B: 200 × magnification; C: 400 × magnification. Arrows indicate gastric signet ring cells.

Figure 3 Pathological features of bone marrow failure demonstrating fibrosis, necrosis, dysplastic hematopoiesis, and iron overload. A: Bone marrow biopsy showing disappearance of typical hematopoietic structure, with necrotic and fibrotic areas (HE staining; 100 ×); B: Enlarged view of fibrotic area showing fibroblast and capillary proliferation with red blood cell extravasation (HE staining; 400 ×); C: Enlarged view of the necrotic area showing extensive coagulative necrosis with some cells exhibiting eccentric nuclei (suspected signet ring cells) and nuclear debris (HE staining; 800 ×); D: Bone marrow smear showing low-level hyperplasia, decreased granulocytic series, active erythroid series, absence of megakaryocytes, and bone marrow particles (Wright staining; 400 ×); E: Bone marrow smear showing absence of bone marrow particles and 74% positive iron staining (Iron staining; 400 ×); F: Peripheral blood smear showing normal proportions of mature granulocytes and lymphocytes, with visible immature red and white blood cells and unevenly distributed platelets (Wright staining; 400 ×).