Goblet Cell Carcinoid/Mixed Adenocarcinoma-Carcinoid Scott R. Owens, MD Key Facts Terminology Goblet cell carcinoid Proliferation of mucin-producing cells with features of both neuroendocrine and crypt/glandular differentiation Clinical Issues Some suggest…

Hirschsprung Disease Alexandros D. Polydorides, MD, PhD Key Facts Terminology Heterogeneous developmental disorder Absent ganglion cells in distal large intestine Etiology/Pathogenesis Failure of neural crest cell migration (embryogenesis) 5-10% familial,…

Mucinous Cystic Neoplasms Scott R. Owens, MD Key Facts Terminology Mucinous cystic neoplasm Circumferential proliferation of low-grade or high-grade dysplastic, mucin-producing epithelium that may distend appendix and fill it with…

Carcinoid Tumor, Appendix Scott R. Owens, MD Key Facts Clinical Issues Found in up to 1.5% of patients undergoing appendectomy Appendiceal CTs occur at younger mean age than CTs in…

Serrated Polyps, Appendix Scott R. Owens, MD Key Facts Clinical Issues May present as acute appendicitis May be incidental finding If no invasive carcinoma present, prognosis is excellent Macroscopic Features…

Fibrous Obliteration Scott R. Owens, MD Key Facts Terminology Fibrosing process → loss of normal mucosal and lymphoid structures, may occlude appendiceal lumen Etiology/Pathogenesis Many associated with neural proliferations (“neuromas”)…

Waldenstrom Protein Scott R. Owens, MD Key Facts Etiology/Pathogenesis Often associated with lymphoplasmacytic lymphoma (LPL) Clinical Issues Diarrhea and malabsorption may lead to intestinal biopsy Microscopic Pathology Dilated mucosal lymphatics…

Carcinoid Joel K. Greenson, MD Key Facts Clinical Issues Carcinoid syndrome (< 10% of patients) Most often asymptomatic incidental finding 2/3 of patients with carcinoid syndrome get fibrous endocardial thickening…

Gangliocytic Paraganglioma Elizabeth A. Montgomery, MD Key Facts Clinical Issues Overwhelming majority in duodenum Benign in majority of cases Rare reports of regional metastases No reports of tumor-associated deaths Microscopic…

Mycobacterium tuberculosis Laura W. Lamps, MD Key Facts Clinical Issues GI symptoms, rather than pulmonary, may be initial presentation Macroscopic Features Frequency of involvement: Ileocecum > jejunoileum > appendix >…