Bone marrow biopsy for treatment-refractory thrombocytopenia was performed by an interventional radiologist, which revealed mild hypercellularity and small-cell metastatic high-grade neuroendocrine cancer with Ki-67 > 90%, likely primary tumor in the rectum (Figs. 3–5). The gene discussed is MKI67; the disease is neuroendocrine carcinoma.