Gastric carcinoids in a patient with pernicious anemia and familial adenomatous polyposis

Primary high-grade neuroendocrine carcinoma emerging from an adenomatous polyp in the setting of familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a rare inherited syndrome that is characterised by innumerable adenomas of the colon and rectum, a high risk of colorectal cancer and a variety of extracolonic manifestations. FAP presents as hundreds to thousands of colonic adenomas beginning in adolescence. The syndrome is associated with less than 1% of all colorectal cancer cases, but there is a nearly 100% lifetime risk of colorectal cancer in individuals with FAP. This case demonstrates a 60-year-old man with FAP who developed high-grade neuroendocrine carcinoma with glandular and squamous differentiation, and regional lymph node and liver metastases. Early diagnosis of FAP is of the utmost importance to start screening colonoscopies to assess disease burden, perform polypectomies and to make management decisions. Neuroendocrine carcinomas rarely occur in patients with FAP, and awareness of this association among general medical physicians and pathologists is essential for the diagnosis and care of these patients.

Appendix carcinoids in childhood: long-term experience at a single institution in Western Canada and systematic review

BACKGROUND

The aim of this study was to describe the management experience of children with appendix carcinoids (AC).

METHOD

A systematic review of the literature pertaining to AC in the pediatric population was performed. PubMed, EMBASE and SCOPUS and most significant Congress proceedings were reviewed. In addition, charts and files at Stollery Children's Hospital, University of Alberta, Edmonton, Canada, were retrieved and the data compared with the scientific literature review.

RESULTS

Between January 2000 and October 2010, seven patients had AC at the authors' institution. Mean age at diagnosis was 15 years while the male : female ratio was 3:4. Five out of seven patients presented with acute appendicitis. Size ranged up to 1.4 cm. In one case only lymph node metastases were observed. No distant metastases were seen in any patient. Carcinoid was low grade in all seven children. One patient suffered from familial adenomatous polyposis. At a mean follow up of 53.4 months, the outcome was excellent with all patients alive without disease. In the systematic review, 206 studies referring to AC in children were identified. Most series on childhood AC were small single-center series with 2-19 patients.

CONCLUSIONS

Older age (>10 years) at diagnosis, female preponderance, and tumor diameter <1.5 cm were the salient observations in the present study. Surgical resection at an early stage allows for excellent prognosis without the need for any additional surgical or adjuvant treatment. Genetic counseling may be appropriate in view of the possible association with colonic adenocarcinoma.

[Familial adenomatous polyposis and liver metastases from a neuroendocrine tumor]

Familial adenomatous polyposis (FAP) is mainly characterized by the development of a large number of polyps in the gastrointestinal tract and by the risk of developing adenocarcinomas. We present the case of a woman diagnosed with FAP and liver metastases. Histological analysis revealed both diseases to be secondary to a neuroendocrine tumor. To date, only three cases showing the simultaneous occurrence of these two entities have been published. Currently, there is no genetic basis to explain the coexistence of these two diseases, both of which have a very low prevalence.

Haploinsufficiency of Apc leads to ineffective hematopoiesis

Loss of a whole chromosome 5 or a deletion of the long arm of chromosome 5, -5/del(5q), is a recurring abnormality in myeloid neoplasms. The APC gene is located at chromosome band 5q23, and is deleted in more than 95% of patients with a -5/del(5q), raising the question of whether haploinsufficiency of APC contributes to the development of myeloid neoplasms with loss of 5q. We show that conditional inactivation of a single allele of Apc in mice leads to the development of severe anemia with macrocytosis and monocytosis. Further characterization of the erythroid lineage revealed that erythropoiesis is blocked at the early stages of differentiation. The long-term hematopoietic stem cell (LT-HSC) and short-term HSC (ST-HSC) populations are expanded in Apc-heterozygous mice compared with the control littermates; however, the HSCs have a reduced capacity to regenerate hematopoiesis in vivo in the absence of a single allele of Apc. Apc heterozygous myeloid progenitor cells display an increased frequency of apoptosis, and decreased in vitro colony-forming capacity, recapitulating several characteristic features of myeloid neoplasms with a -5/del(5q). Our results indicate that haploinsufficiency of Apc impairs hematopoiesis, and raise the possibility that loss of function of APC contributes to the development of myelodysplasia.

Upper gastrointestinal carcinoid tumors incidentally found by endoscopic examinations

AIM

This study shares Asian clinical experiences of carcinoid tumors that originated in the upper gastrointestinal tract.

METHODS

From May 1987 to June 2002, we had found only 13 cases of histologically confirmed carcinoid tumors in the upper gastrointestinal tract by endoscopic examinations. There were eight males and five females. The mean age was 53.16+/-20.51 years that ranged from 26 to 82 years. Each of their clinical presentations, locations, tumor morphology, and size and the treatment outcome were analyzed and discussed.

RESULTS

One patient had a polypoid lesion at the lower esophagus, nine were stomach lesions and three located at the duodenum. All patients with polypoid and submucosal tumor types were of small size (<1.7 cm) and all patients survived after simple excision or polypectomy. Four of the five patients in tumor mass forms died and the tumors were more than 2.0 cm in size.

CONCLUSION

Carcinoid tumors rarely originated from the upper gastrointestinal tract and are usually found accidentally after endoscopic study. Bigger size (more than 2 cm) tumor masses may indicate a more severe disease and poor prognosis.

Composite Glandular and Endocrine Tumors of the Stomach With Pancreatic Acinar Differentiation

Composite tumors of the stomach consisting of mixed glandular and endocrine components are rare. We report 3 cases of composite glandular and endocrine tumors with pancreatic acinar differentiation in the stomach with their clinicopathologic findings. The patients' presenting symptoms were variable and included abdominal pain, gastrointestinal hemorrhage, and weight loss. One patient with abdominal pain also had an elevated serum lipase level, clinically mimicking acute pancreatitis. The histology of these tumors was similar. They showed admixture of well-differentiated endocrine components with acinar and glandular components. The glandular component consisted of columnar epithelial cells resembling gastric foveolar or intestinal goblet cells, consistent with a well-differentiated adenocarcinoma. A panel of histochemical and immunohistochemical stains was performed, which included PAS, Alcian blue, Mib1, CEA, cytokeratin 7, cytokeratin 20, Muc2, Muc5AC, chromogranin, synaptophysin, trypsin, chymotrypsin, lipase, insulin, gastrin, serotonin, and pancreatic polypeptide. While the immunoreactivity for cytokeratin 7, cytokeratin 20, Muc2, Muc5AC, and CEA was largely restricted to the glandular component, the endocrine and pancreatic acinar markers showed marked variability and overlap. All cases showed immunoreactivity for at least one of the exocrine pancreatic enzymes, and all expressed endocrine differentiation. Some degree of amphicrine differentiation was suggested in all cases. Two cases showed metastases in perigastric lymph nodes, which histologically resembled the primary tumor. In summary, these tumors represent another distinct type of composite glandular and endocrine gastric neoplasm with pancreatic acinar differentiation.

FAP with concurrent duodenal adenomatous polyposis and carcinoid tumor

We report a patient with familial adenomatous polyposis (FAP) who developed duodenal adenomatosis with high-grade dysplasia and a periampullary carcinoid tumor several years after total colectomy. Only two prior case reports exist revealing carcinoid tumors in association with FAP. No genetic basis exists explaining the link between FAP and carcinoid tumors. However, the presence of two rare entities in the same patient might suggest an association and further research may be indicated.

Absorption of water-soluble vitamins

Water-soluble vitamins are required as enzyme cofactors in a wide variety of metabolic reactions. Riboflavin, niacin, and vitamin C are essential in redox reactions; thiamine and biotin are involved in macronutrient metabolism; and folate, vitamin B12, pyridoxine, and riboflavin play important roles in the regulation of S-adenosylmethionine production and DNA synthesis. Each of the water-soluble vitamins appears to require its own membrane transport process for absorption across the enterocyte. The absorption of vitamin B12, or cobalamin (Cbl), is unique in requiring multiple processes from the stomach to the ileum that involve at least four different binding proteins. Whereas all water-soluble vitamins are absorbed from the small intestine, folate, biotin, and riboflavin can be transported across colonic epithelial cells, with uncertain clinical significance. This article reviews recent studies on the requirement, metabolism, and deficiency state of each water-soluble vitamin, followed by a discussion of current knowledge on the regulation of its intestinal absorption.