Neuroendocrine tumors of the extrahepatic biliary tree are extremely rare malignancies accounting for 0.2-2.0% of all gastrointestinal carcinoid tumors. Neuroendocrine tumors obstructing the biliary tree are extremely difficult to diagnose preoperatively and nearly impossible to differentiate from cholangiocarcinoma. Statistically, the most common anatomic location in the biliary tree is the common bile duct, followed by the perihilar region. Herein, we present a case of a small cell neuroendocrine carcinoma of the hilum in a 79-year-old man following laparotomy. To our knowledge, this is the first case of small cell type neuroendocrine carcinoma of hilar bile duct reported in Korea.
Aged ; Bile Duct Neoplasms/*diagnosis/pathology/surgery ; Cholangiopancreatography, Endoscopic Retrograde ; Diagnosis, Differential ; Hepatic Duct, Common/pathology ; Humans ; Male ; Neuroendocrine Tumors/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed

Neuroendocrine tumor (NET) is a cancer-like tumor that occurs mostly in the gastrointestinal system. Within the gastrointestinal tract, NET most commonly occurs in the rectum whereas appendix is very rarely involved. In most cases of appendiceal NET, it is found at a relatively early stage compared to other NETs because appendiceal NET frequently presents with acute appendicitis because appendiceal NET frequently presents with acute appendicitis even when the size is smaller than 1 cm. Therefore, it is very rare for lymph node metastasis to occur in a young adult. Herein, we report a rare case of grade 1 appendiceal NET with lymph node metastasis which developed in a teenage male.
Adolescent ; Appendiceal Neoplasms/*diagnosis/pathology/surgery ; Carcinoid Tumor/diagnosis/pathology ; Colectomy ; Colonoscopy ; Humans ; Lymphatic Metastasis ; Male ; Neuroendocrine Tumors/*diagnosis/pathology ; Tomography, X-Ray Computed

Carcinoids are slow growing neuroendocrine tumors (NET) originating in the enterochromaffin cells of the gastrointestinal tract. In previous studies, rectal NET comprised only about 1% of all anorectal neoplasms; however, the incidence of rectal NET has shown a recent increase. Typically, rectal NET presents as a single subepithelial nodule, and multicentricity of rectal NETs is rare, with reported incidence of 2-4.5%. Due to the rarity of multiple rectal NETs, there is no consensus or guidelines for treatment of multiple rectal NETs. However, NETs of the rectum that are less than 10 mm in diameter and do not infiltrate the muscularis propria, without distant metastasis, can be removed by endoscopy, as with solitary rectal NET. We encountered five cases of multiple rectal NETs which were treated successfully by endoscopy.
Adult ; Aged ; Colonoscopy ; Female ; Humans ; Male ; Middle Aged ; Neuroendocrine Tumors/*diagnosis/pathology/surgery ; Positron-Emission Tomography ; Rectal Neoplasms/*diagnosis/pathology/surgery ; Sigmoidoscopy ; Tomography, X-Ray Computed

OBJECTIVETo study the clinicopathologic features and differential diagnosis of 18 cases of endocrine ductal carcinoma-in-situ (E-DCIS).

METHODSEighteen cases of breast cancer with features of E-DCIS were studied by light microscopy, histochemistry and immunohistochemistry. E-DCIS was diagnosed if the histologic patterns were compatible with those described in the literature and at least 50% of the tumor cells expressing two of the three neuroendocrine markers employed (chromogranin, synaptophysin and neuron-specific enolase).

RESULTSE-DCIS tended to occur in older women. All the patients were over 61 years old (mean age=71 years). The presenting symptoms were either palpable breast mass or had nipple discharge. Histologically, E-DCIS demonstrated an expansile intraductal growth pattern. Intraductal papilloma was not uncommon at the peripheral area of the tumor. The tumor cells were polygonal, oval or spindle in shape and contained abundant eosinophilic to granular cytoplasm and mildly to moderately pleomorphic nuclei. Intracellular or extracellular mucin was highlighted by periodic acid-Schiff (with diastase digestion) or alcian blue stains. Some tumor cells assumed a signet-ring configuration. All the three neuroendocrine markers were expressed by more than 50% of the E-DCIS cells. The neuroendocrine differentiation was further confirmed in some cases by CD57 and CD56 immunostaining. Pagetoid spread into adjacent ductolobular units was frequently seen in E-DCIS, and the expanded lobules were often not rimmed by myoepithelial cells. These two features helped to distinguish E-DCIS from usual ductal hyperplasia.

CONCLUSIONSE-DCIS represents a subgroup of low-grade DCIS, which carries characteristic morphologic features and immunophenotype. Conventional light microscopy usually permits a correct diagnosis. Ancillary histochemical and immunohistochemical studies can be helpful in doubtful cases.

Aged ; Breast Neoplasms ; metabolism ; pathology ; surgery ; Carcinoma in Situ ; metabolism ; pathology ; surgery ; Carcinoma, Intraductal, Noninfiltrating ; metabolism ; pathology ; surgery ; Chromogranin A ; metabolism ; Diagnosis, Differential ; Female ; Humans ; Immunohistochemistry ; Mastectomy ; methods ; Middle Aged ; Neuroendocrine Tumors ; metabolism ; pathology ; surgery ; Phosphopyruvate Hydratase ; metabolism ; Synaptophysin ; metabolism

Gastrointestinal neuroendocrine tumors arise from cells of the diffuse neuroendocrine system and can take place almost anywhere within the gastrointestinal tract. A 40-year-old man admitted to evaluate a duodenal subepithelial lesion which was incidentally found at health check-up. The polypoid duodenal subepithelial lesion, measuring about 7 mm, was removed by the endoscopic mucosal resection and the pathology confirmed a neuroendocrine tumor. Abdominopelvic computed tomography, done for staging work up, revealed a mass in the pancreatic head and the patient received pylorus preserving pancreaticoduodenectomy. Mass at the pancreas also found out to be neuroendocrine tumor but showed different histopathologic traits under immunohistochemical staining. The patient was also diagnosed as hyperparathyroidism and pituitary microadenoma. Finally, multiple endocrine neoplasia type 1 was confirmed, which was accompanied by duodenal neuroendocrine tumor.
Adult ; Antigens, CD56/metabolism ; Duodenum/*pathology ; Endoscopy, Digestive System ; Humans ; Immunohistochemistry ; Magnetic Resonance Imaging ; Male ; Neoplasms, Multiple Primary ; Neuroendocrine Tumors/*diagnosis/metabolism/surgery ; Pancreas/*pathology ; Synaptophysin/metabolism ; Tomography, X-Ray Computed

Gastrointestinal neuroendocrine tumors arise from cells of the diffuse neuroendocrine system and can take place almost anywhere within the gastrointestinal tract. A 40-year-old man admitted to evaluate a duodenal subepithelial lesion which was incidentally found at health check-up. The polypoid duodenal subepithelial lesion, measuring about 7 mm, was removed by the endoscopic mucosal resection and the pathology confirmed a neuroendocrine tumor. Abdominopelvic computed tomography, done for staging work up, revealed a mass in the pancreatic head and the patient received pylorus preserving pancreaticoduodenectomy. Mass at the pancreas also found out to be neuroendocrine tumor but showed different histopathologic traits under immunohistochemical staining. The patient was also diagnosed as hyperparathyroidism and pituitary microadenoma. Finally, multiple endocrine neoplasia type 1 was confirmed, which was accompanied by duodenal neuroendocrine tumor.
Adult ; Antigens, CD56/metabolism ; Duodenum/*pathology ; Endoscopy, Digestive System ; Humans ; Immunohistochemistry ; Magnetic Resonance Imaging ; Male ; Neoplasms, Multiple Primary ; Neuroendocrine Tumors/*diagnosis/metabolism/surgery ; Pancreas/*pathology ; Synaptophysin/metabolism ; Tomography, X-Ray Computed

OBJECTIVETo analyze the clinicopathologic and immunohistochemical features of nodular histiocytic/mesothelial hyperplasia (NHMH) and to improve the knowledge of this disease.

METHODSSeven cases of NHMH were collected and the clinicopathologic and immunohistochemical data were analyzed with review of the literature.

RESULTSSeven male patients aged from 1.5 to 5.0 years (mean 2.8). The main clinical symptom was an inguinal mass.Grossly, main pathological changes were the mural nodule or free nodule in lumen, with diameter of 0.1-0.5 cm.Histologically, the tumor cell morphology was relatively single, cohesive polygonal or oval cells which were arranged in solid sheets or nests, usually with ovoid or deeply grooved nuclei and a moderate amount of pale pink cytoplasm in the nodular collection area. The nuclei had delicate chromatin and no obvious atypia, and mitosis was incidentally found. A few scattered lymphocytes were found in the stroma. The cyst wall was lined by a single layer of mesothelial cells.Immunohistochemically, the most cells in nodular lesion were strongly positive for the histiocytic marker CD68, vimentin and α1-antichymotrypsin, while lining mesothelial cells on the wall were positive for calretinin, MC, WT1, CK5/6, CKpan and EMA.

CONCLUSIONSNHMH is a rare and benign tumor-like lesion, and easy to be misdiagnozed, which should be distinguished from neuroendocrine tumors, Langerhans cell histiocytosis, seminoma, mesothelioma and so on. The correct diagnosis of this lesion depends on the clinical characteristics, morphology and immunohistochemistry.

Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Calbindin 2 ; metabolism ; Child, Preschool ; Diagnosis, Differential ; Epithelium ; metabolism ; pathology ; surgery ; Histiocytes ; metabolism ; pathology ; Histiocytosis, Langerhans-Cell ; metabolism ; pathology ; Humans ; Hyperplasia ; metabolism ; pathology ; surgery ; Infant ; Leukocyte Common Antigens ; metabolism ; Male ; Mesothelioma ; metabolism ; pathology ; Mucin-1 ; metabolism ; Neuroendocrine Tumors ; metabolism ; pathology ; Seminoma ; metabolism ; pathology ; Vimentin ; metabolism ; WT1 Proteins ; metabolism ; alpha 1-Antichymotrypsin ; metabolism

Humans ; Hypoxia-Inducible Factor-Proline Dioxygenases ; metabolism ; Ki-67 Antigen ; metabolism ; MicroRNAs ; metabolism ; Neoplasm Grading ; Neoplasm Staging ; Neprilysin ; metabolism ; Neuroendocrine Tumors ; classification ; diagnosis ; metabolism ; pathology ; surgery ; PAX8 Transcription Factor ; Paired Box Transcription Factors ; metabolism ; Pancreatic Neoplasms ; classification ; diagnosis ; metabolism ; pathology ; surgery ; Prognosis ; Tumor Suppressor Proteins ; metabolism