Pancreas neoplasia

Fig.7.8a,b. Pyogenic abscess, a Pyogenic abscess in a 35-year old man status post laparoscopic right hepatectomy due to an hydatid cyst. Portal venous-phase contrast-enhanced CT scan shows a thick-walled cystic lesion with homogeneous low attenuation. b Pyogenic abscess with presence of gas within the lesion in a 52-year-old man with fever, head of pancreas neoplasia (not resectable due to superior mesenteric vein infiltration) and recent portal thrombosis. An axial portal phase CT scan shows an hypoattenuating lesion with non-homogeneous content and gas inside... 

Exposure to 0.05-0.5 ppm 1,1-dimethylhydrazine for 6 months produced an increased incidence of leukemia and tumors of the pancreas, pituitary, blood vessels, liver, and thyroid in mice and/or rats (Haun et al. 1984). Tumors of the lung, liver, nasal cavity, bone, and blood vessels were observed in mice exposed to 5 ppm 1,1-dimethylhydrazine for 1 year (Haun et al. 1984). A significantly increased incidence (p 0.05) of nasal tumors and thyroid carcinomas was observed in male rats exposed intermittently to 1 and 5 ppm hydrazine, respectively, for 1 year (Vemot et al. 1985). Hamsters and rats exposed to 750 ppm hydrazine once for 1 hour, or 1 hour per week for 10 weeks, exhibited increased incidences of squamous metaplasia, hyperplasia, and neoplasia in the nose (Latendresse et al. 1995). Nasal tumors were also noted in hamsters and female rats intermittently exposed to 5 ppm hydrazine for 1 year (Vemot et al. 1985). Tumor incidence was not significantly increased in mice and dogs exposed intermittently to 1 ppm hydrazine for 1 year (Vemot et al. 1985). The studies suggest that hydrazine and... 

Synaptophysin, also called protein p38, is a glycoprotein initially found in small vesicle membranes of neurons and of chromaffin cells in the adrenal medulla. It has been routinely used as a broad-spectrum marker in normal and neoplastic neuroendocrine cells including those of the pancreas however, strong synaptophysin immunoreactivity has been well-documented in tumors without any endocrine differentiation including solid-pseudopapillary neoplasm (SPN) of the pancreas, which is one of the most important differential diagnoses of endocrine neoplasia in this organ. 

Serous cystadenoma (SCA) is the only nonmucinous example of ductal neoplasia in the pancreas and, unlike other ductal tumors, has virtually no tendency for malignant transformation. It is also known to have a well-established association with von Hippel-Lindau (vHL) syndrome. iez... 

Pancreatic endocrine neoplasms (PENs) are the majority of the endocrine neoplasms in the pancreas.Most PENs are sporadic. However, these tumors also constitute one of the major components of the multiple endocrine neoplasia I (MENl) syndrome or may arise in patients with vHL syndrome. Those that are associated with increased serum levels of hormones and lead to corresponding symptoms are referred to as functional and are named according to which hormone they secrete (e.g., insulinoma—42% of all functional variants, gastrinoma—24%, glucagonoma—14%,... 

Adsay NV, Merati K, Andea A, et al. The dichotomy in the pre-invasive neoplasia to invasive carcinoma sequence in the pancreas differential expression of MUCl and MUC2 supports the existence of two separate pathways of carcinogenesis. Mod Pathol. 2002 15 1087-1095. 

Basturk O, Khanani F, Sarkar F, et al. DeltaNp63 expression in pancreas and pancreatic neoplasia. Mod Pathol. 2005 18 1193-1198. 

Adsay NV, Basturk O, Gheng JD, Andea AA. Ductal neoplasia of the pancreas nosologic, clinicopathologic, and biologic aspects. Semin Radiat Oncol. 2005 15 254-264. 

Mulliplc endocrine neoplasias are inherited disorders. The syndromes are usually transmitted in an autosomal dominant pattern. The endocrine glands most often affected are the parathyroid, pituitary, pancreas, thyroid and adrenal. It is postulated that the cell types involved in these tumours have a common embryological precursor. There arc three well-dcrmed multiple endocrine neoplasia syndromes (Fig. 2). 

In the pediatric population, pancreatic tumors are very unusual entities. They account for less than 5% of all malignancies in children. These tumors may arise from the exocrine or endocrine pancreas. Exocrine neoplasias include ductal adenocarcinoma, acinar adenocarcinoma, pancreaticoblastoma, or infantile adenocarcinoma. Endocrine tumors or islet cell tumors are named after the hormone produced, with insulinoma being the most common in children (Walker 1996). 

Neoplasias that arise from the endocrine portion of the pancreas can be classified as secretory or non-secretory (Gouya et al. 2003). When secretory, the endocrine tumor will be subclassified according to the type of hormone produced (insulin hormone, gastrin hormone, or active peptides). Insulinomas are the most common endocrine tumors, while glucagonomas or somatostatinomas have not been reported in children. 

Another area worthy of future investigation is the treatment of non-colorectal, non-neuroendocrine cancers metastatic to the liver. Often referred to as mixed neoplasia, these refer to patients with liver-dominant metastatic disease to the liver from various primaries (breast, melanoma, pancreas, and lung). Although several reports have been described, controlled phase II studies using time-to-progression, tumor response, or progression-free-survival would be clinically relevant given the dearth of options for some of these patients [51-54]. 

The initial hazard identification of pancreatic toxicity in a prechnical study is always concerning because of the potentially serious human health risks, which may include fulminant, hfe-threatening cases of DIAP or a lifelong iUness, such as CP, type 1 diabetes, or pancreatic neoplasia. Because both the exocrine and the endocrine pancreas have enormous reserve capacities and there are limited sensitive and specific biomarkers to detect pancreatic injury in both animals and humans, there is always the concern that subclinical DIAP may initially go undetected in humans. Further, AP may progress until a threshold of severity is evident in minimally or asymptomatic healthy human volunteers exposed to drug candidates with unknown risks and/or in previously healthy patients that receive standard-of-care agents with marked... 

Recurrent anastomotic ulcers when they occur are usually found on the jejunal side of the anastomosis (Fig. 5.8a). In patients who present with persistent or complex duodenal or anastomotic ulcer, especially if associated with diarrhoea, weight loss, and liver metastasis, Zollinger-Ellison syndrome should be suspected. The syndrome consists of recurrent intractable peptic ulcers caused by hypergastrinae-mia produced by gastrin-secreting tumours of the pancreas (75%) or duodenum (15%) (Hirschowitz 1997). Tumour localisation is critical to aid in the identification of patients with potentially respectable disease (Berg and Wolfe 1991). Twenty percent of patients have multiple endocrine neoplasia type I which includes parathyroid, pituitary, and adrenal tumours. 

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