Early Definitive Diagnosis and Management of Incidental Neuroendocrine Tumors Found on Gastrointestinal Endoscopy.

Neuroendocrine tumors (NETs) are tumors that originate from neuroendocrine cells and can be found throughout the body but are most commonly seen in the gastrointestinal tract, pancreas, and lungs. There is an increase in the diagnosis of NETs due to advances in diagnostic modalities. Although mucosal tumors are easily visualized on upper GI endoscopic imaging, neuroendocrine tumors are often missed due to their deep mucosal origin with normal overlying mucosa. We first present the case of a 46-year-old woman with anemia and epigastric discomfort who was found to have an incidental submucosal mass in the duodenal bulb on esophagogastroduodenoscopy (EGD), which on endoscopic ultrasound (EUS) with a fine needle biopsy (FNB) showed a neuroendocrine tumor. Imaging with CT, however, failed to detect the presence of the mass in the duodenum. Furthermore, a DOTATATE scan showed only a nonspecific signal near the liver. The patient then underwent an EGD-guided, laparoscopic, robot-assisted transduodenal resection of the tumor, together with the removal of enlarged peritumoral lymph nodes. Pathology showed a well-differentiated neuroendocrine tumor of the duodenal bulb with metastasis to one lymph node, which was confirmed via immunohistochemistry staining. The second case is of a 51-year-old female who presented with occasional constipation and rectal pain and was found to have a rectal polypoid lesion on her colonoscopy, jumbo biopsies of which revealed a NET. An EUS done for staging and endoscopic mucosal resection (EMR) revealed a grade 1 well-differentiated NET on pathology, which was confirmed by immunohistochemistry staining. These cases stress the need for timely, definitive diagnosis and intervention. Here, we discuss the clinical features and investigations of neuroendocrine tumors for early diagnosis and management.

Noncirrhotic portal hypertension in primary biliary cholangitis with coexisting CREST syndrome.

Primary Biliary Cholangitis (PBC) is an autoimmune liver disease that is sometimes associated with CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) syndrome. If left untreated, PBC eventually progresses to liver cirrhosis. We describe an adult patient with CREST-PBC who presented with recurrent variceal bleeding and ultimately required transjugular intrahepatic portosystemic shunt (TIPS) insertion. Liver biopsy excluded cirrhosis, resulting in a diagnosis of noncirrhotic portal hypertension. This case report describes the pathophysiology of presinusoidal portal hypertension as a rare complication of PBC and its association with coexisiting CREST.

A Rare Case of Histiocytic Sarcoma Secondary to Gastrointestinal Stromal Tumor in the Stomach: Transdifferentiation or Synchronicity?

Histiocytic sarcoma is a rare malignant histiocytic neoplasm composed of cells with morphologic and immunophenotypic features of mature tissue histiocytes. It occurs anywhere in the body and behaves aggressively. However, its etiology is unknown. Here, we report a 68-year-old female who developed histiocytic sarcoma following chemotherapy with imatinib (Gleevec) for gastrointestinal stromal tumor. Possible mechanisms of transdifferentiation from gastrointestinal stromal tumor to histiocytic sarcoma are discussed based on the features of our case and other two similar cases in the literature.

Polypoid Undifferentiated Carcinoma With Osteoclast-like Giant Cells Arising in the Distal Common Bile Duct: A Rare Case Report.

BACKGROUND: Undifferentiated carcinoma with osteoclast-like giant cells (UC-OGC) in distal common bile duct (CBD) is a rare entity. CASE REPORT: This case report describes a 45-year-old male with a history of a choledochal cyst status post partial excision and cholecystectomy who presented with a mass in the remaining distal/intrapancreatic common bile duct. It was initially mistaken for post-surgery hematoma; however, the rapid growth raised concern for malignancy, and prompted a pancreaticoduodenectomy (Whipple) procedure. Macroscopic examination revealed a 5.5 cm polypoid mass grossly confined in the lumen of the distal CBD. Histology was consistent with UC-OGC, with minimal invasion into the polyp stalk and adjacent CBD wall. Immunohistochemistry demonstrated co-expression of CK7 and p40, normal/wild-type p53, and retained SMAD4 expression in tumor cells. Next-generation sequencing detected mutations at p.Q61H (c.183A>C) of KRAS and p.E545K (c.1633G>A) of PIK3CA, keeping in line with similarity to conventional cholangiocarcinoma. The patient remained disease-free after two years of follow-up without chemotherapy. CONCLUSION: To our knowledge, this is the first case report of UC-OGC presented as a polypoid mass in the distal CBD. It highlights the complex dynamism and controversial pathogenesis of this unique entity, which should be made aware to avoid diagnostic pitfalls.

Rare Case of Duodenal Metastasis From Pulmonary Squamous Cell Carcinoma.

Pulmonary squamous cell carcinoma is the second most common non-small cell malignancy of the lung. It commonly metastasizes to the adrenal glands, bone, liver, brain, and kidneys. Most occurrences of metastatic squamous cell carcinoma involving the gastrointestinal tract originate from primary lung tumors. Metastasis to the duodenum, however, is exceedingly rare, with very few cases of stomach or duodenal involvement described in the literature. We report the case of a patient with stage IV pulmonary squamous cell carcinoma metastasizing to the duodenum with an uncommon presentation to add to the paucity of literature available regarding this rare finding.

Thoracic Myoepithelial Tumors: A Pathologic and Molecular Study of 8 Cases With Review of the Literature.

Thoracic myoepithelial tumors (MTs) are a rare group of tumors showing predominant or exclusive myoepithelial differentiation. They are poorly characterized from both a morphologic and genetic standpoint, in particular features that separate benign from malignant behavior. We examined the histologic and immunohistochemical features of 8 primary thoracic MTs and performed fluorescence in situ hybridization for EWSR1, FUS, PLAG1, and HMGA2, as well as several partner genes. Half (4/8) of the MTs occurred in large airways, and 3 had infiltrative borders. All cases showed immunoreactivity for epithelial markers, in conjunction with S100 protein or myogenic markers. MTs showed morphologic characteristics analogous to MTs at other sites, with no tumors having ductal differentiation. Necrosis and/or lymphovascular invasion was present in 5 cases, with mitotic activity ranging from 0 to 6 mitoses/2 mm² (mean 1). Metastases occurred in 2 cases, and no patients died of disease. Gene rearrangements were identified in half of the cases, with EWSR1-PBX1, EWSR1-ZNF444, and FUS-KLF17 fusions identified in 1 case each and 1 case having EWSR1 rearrangement with no partner identified. No cases were found to have HMGA2 or PLAG1 abnormalities. Compared with fusion-negative tumors, fusion-positive tumors tended to occur in patients who were younger (50 vs. 58 y), female (1:3 vs. 3:1 male:female ratio), and demonstrated predominantly spindle and clear cell morphology. Using a combined data set of our case series with 16 cases from the literature, poor prognosis was significantly correlated with metastases (P=0.003), necrosis (P=0.027), and ≥5 mitoses/2 mm²/10 high-power field (P=0.005). In summary, we identify a subset of thoracic MTs harboring rearrangements in EWSR1 or FUS, and our data suggest that necrosis and increased mitotic activity correlate with aggressive clinical behavior.

Endotracheal myoepithelioma.

Myoepitheliomas have been described most commonly in salivary glands and have been reported elsewhere but are rare in the lung, with only six previously reported cases. To our knowledge, this represents the first endotracheal myoepithelioma. These tumors have characteristic features that distinguish them from other tumors, and the diagnosis is a pathologic one, based on the morphology and supported by immunohistochemistry. Myoepitheliomas should be considered in the diagnosis of any pulmonary nodule.

Appendiceal mucinous cystadenoma is a neoplastic complication of IBD: case-control study of primary appendiceal neoplasms.

BACKGROUND: IBD is a risk factor for development of colorectal neoplasia. Although IBD frequently involves the appendix microscopically, it is uncertain whether it also predisposes to appendiceal neoplasia. METHODS: We performed a retrospective case-control study of incidental appendiceal neoplasms in colectomy specimens of adults with and without IBD (cases and controls, respectively) based on surgical pathology records spanning 54 months. To minimize referral bias, patients were excluded if they had preoperative clinical evidence or a principal pathologic diagnosis of appendiceal disease. The pathologic diagnoses were confirmed retrospectively. RESULTS: Eleven appendiceal cystadenomas and 6 appendiceal carcinoid tumors were identified among 705 IBD cases (377 ulcerative colitis, 317 Crohn's disease, 11 indeterminate colitis) and 498 non-IBD controls meeting our inclusion criteria. There was no significant difference in prevalence of cyst adenomas between the cases and controls (9/705 [1.3%] versus 2/498 [0.4%], respectively, OR 3.2 [95% CI 0.7-14.9]). However, cyst adenomas were 15-fold more prevalent among cases with synchronous colorectal neoplasia compared with controls (4/69 [5.8%] versus 2/498 [0.4%], OR 15.3 [95% CI 2.7-85]) and 8-fold higher compared with cases without synchronous neoplasia (4/69 [5.8%] versus 5/636 [0.8%], OR 7.8 [95% CI 2.0-29.6]). Appendiceal carcinoids were equally prevalent in cases and controls (4/705 [0.6%] versus 2/498 [0.4%], OR 1.4 [95% CI 0.3-7.8]), cases with synchronous neoplasia and controls (1/69 [1.4%] versus 2/498 [0.4%], OR 3.6 [95% CI 0.3-40.8]), and cases with and without synchronous colorectal neoplasia (1/69 [1.4%] versus 3/636 [0.5%], OR 3.1 [95% CI 0.3-30.2]). CONCLUSIONS: IBD with synchronous colorectal dysplasia or cancer is a risk factor for development of appendiceal cystadenomas, implicating this tumor as a neoplastic complication of IBD. IBD does not predispose to the development of appendiceal carcinoids.

Cavernous, arteriovenous, and mixed hemangioma-lymphangioma of the rectosigmoid: rare causes of rectal bleeding--case series and review of the literature.

INTRODUCTION: Cavernous hemangiomas of the sigmoid colon and rectum are uncommon vascular malformations usually found in young adults with a long history of episodic and painless rectal bleeding. Alternatively, they may present with massive life-threatening hemorrhage. DISCUSSION: We report three cases of hemangioma of the rectosigmoid including one case of cavernous hemangioma, one case of arteriovenous hemangioma, and one case of hemangiolymphangiomatosis with emphasis on clinical presentation, radiologic, operative, and pathologic findings. Definitive treatment consists of complete resection with a sphincter-preserving procedure or abdominoperineal resection, based on extent of disease. CONCLUSION: Therapy is typically delayed by several years in these patients due to erroneous diagnosis and failed treatment of hemorrhoids and inflammatory bowel disease. Relative to hemangiomas, lymphangiomas of the rectosigmoid are even more rare and when symptomatic, present with rectal bleeding and pelvic pain.

Abdominal mucinous cystic neoplasm in a male child.

Mucinous cystic neoplasms (MCNs) make up a morphologic family of similar appearing tumors arising in the ovary and various extraovarian sites, including the pancreas, hepatobiliary tract, paratesticular soft tissues, and mesentery. Other than the uncommon mucinous cystadenoma of the ovary presenting in adolescence, MCNs are rarely seen by the pediatric pathologist. The present case is a 5-year-old boy with an abdominal mass appearing to arise in the mesentery of the small intestine. Because of its unresectability, a generous biopsy was performed and disclosed a MCN with focal complex papillary architecture in the absence of appreciable cytologic atypia or invasion into the wall. Like other MCNs, this tumor had an inhibin-positive, ovarian-like stroma that was nonreactive for estrogen and progesterone receptors. Only 1 other case of a mesenteric MCN has been reported to date in a child and none in a male. The MCN of the mesentery joins other, somewhat more common cystic lesions of the omentum and mesentery presenting in childhood.

Primary cardiac alveolar soft part sarcoma. A report of the first observed case with molecular diagnostics corroboration.

A case of primary alveolar soft part sarcoma (ASPS) of the heart is reported in an 11-year-old female as 1 of 16 cases of ASPS presenting in the first 2 decades of life in our institutional 17-year review period. The classic alveolar or organoid pattern was inconspicuous as compared to a more diffuse or formless pattern consisting of a population of uniform round cells with abundant eosinophilic cytoplasm, but in addition there was a second, minor population of gigantiform tumor cells with a variety of unusual shapes. Scattered tumor cells contained dense eosinophilic condensations in the cytoplasm. Other unusual features for ASPS in our case included a lymphohistocytic reaction and zonal necrosis. Immunohistochemistry revealed nuclear reactivity for TFE3, and the ASPL-TFE3 fusion transcript was identified by reverse-transcriptase polymerase chain reaction. The only other examples of ASPS involving the heart were 3 cases in the literature of metastatic disease from tumors arising in the soft tissues. This initial case of primary cardiac ASPS joins the list of other types of sarcomas in children that have been reported as primary neoplasms of the heart.

Pilot study on gastric electrical stimulation on surgery-associated gastroparesis: long-term outcome.

OBJECTIVES: Patients with postgastric surgery gastroparesis are often unresponsive to conventional medical therapy. Gastric electrical stimulation (GES) with the use of high-frequency and low-energy neural stimulation is an approved technique for patients with idiopathic and diabetic gastroparesis. METHODS: We hypothesized that GES would improve symptoms, health resource utilization, and gastric emptying in six patients with postsurgical gastroparesis from a variety of surgical procedures. Patients were evaluated by means of the following criteria: symptoms, health-related quality of life, and gastric emptying tests at baseline over time. RESULTS: All patients noted improvements after device implantation for up to 46 months: the frequency score for weekly vomiting went from a baseline of 3.2 down to 0.4 immediately after treatment before settling at 1.4 by the long-term follow up. Total gastrointestinal symptom score went from 36.5 at baseline down to 12.3 before settling at 20.5 at long-term follow up. Improvements were also seen in health-related quality of life and solid and liquid gastric emptying. CONCLUSIONS: We conclude that GES is associated with clinical improvements in this group of patients with either postsurgical or surgery-associated gastroparesis. This pilot study with long-term outcomes offers evidence for a new therapy for otherwise refractory patients with gastroparesis associated with previous surgery.

Gastric electrical stimulation is associated with improvement in pancreatic exocrine function in humans.

OBJECTIVE: To define the possible effects of gastric electrical stimulation (GES) for gastroparesis on pancreatic function, we performed 2 related human studies. METHODS: Fecal elastase values were compared in 2 patient groups: (1) GES devices ON and (2) GES devices OFF and (2) in 3 control groups: (1) no response (NR) to prokinetic medications, (2) positive response (RES) to medications, and (3) normal controls. Polypeptide levels in 7 of 9 GES patients with device ON and OFF, elastase results, GI symptoms (TSS), and heart rate variability (HRV) were compared by paired t tests and/or ANOVA and reported as mean +/- SE. RESULTS: Elastase was different for GES-ON and OFF (508.0 +/- 92.2 vs. GES-OFF 378.6 +/- 87.4, P < 0.05). Elastase was lower in medication NR and RES than in normal controls. Postprandial pancreatic polypeptide was greater with GES ON than OFF (P = 0.07). HRV revealed a lower percentage of change with device ON versus OFF (44.2 +/- 5.5 vs. 48.5 +/- 5.2, P = 0.08) and lower TSS with ON versus OFF (15.9 +/- 4.5 vs. 25.7 +/- 5.3, P < 0.05). CONCLUSIONS: GES improves exocrine pancreatic release, effects autonomic control, and improves GI symptoms, suggesting a possible role for GES in the treatment of pancreatic insufficiency associated with gastroparesis.