No abstract

This is the first documented case of amyloid deposition in pancreatic serous adenoma. We indicate that the source of amyloid is an APP-like precursor secreted by stromal myofibroblasts.

Many immunohistochemical studies have investigated the relationship between immunohistochemical characteristics and histopathological findings in colorectal tumors. One of the most extensively studied markers has been tissue CEA, although the prognostic significance of this and other antigens is still uncertain. The authors report results relative to three tumoral antigens (carcinoembryonic antigen, CEA; tissue polypeptide antigen. TPA, and carbohydrate antigen 19-9, CA 19-9) determined by immunohistochemical methods in tissue samples of 52 colorectal carcinomas. The relationship between the immunohistochemical characteristics of the neoplasms and the clinicopathologic parameters, as well as their influence on the prognosis of the patients, were examined. Positive CEA reaction has a significant relationship with grade of differentiation of the tumor while diffuse cellular expression of this antigen often indicates neoplasms extending beyond the intestinal wall and invading the lymph vessels. The number of tissue antigens expressed is significantly related to the extent of tumor spread through the intestinal wall. A greater incidence of recurrence and shorter disease-free interval and survival were observed in neoplasms that expressed tissue TPA antigen or more than one tissue antigens. In the present study the latter parameter has demonstrated to have independent prognostic significance for the disease-free interval. Immunohistochemical evaluation of antigens in colorectal carcinoma tissue shows a possible independent prognostic value of the antigenic heterogeneity of tumors, which could be related to their different biological behavior.

Clear renal cell carcinomas (RCC) frequently express carbonic anydrase IX (CA IX) because of non-functional mutation of von Hippel Lindau (VHL) tumor suppressor gene. CA IX is a tumor-associated transmembrane antigen, which catalyzes the extracellular, reversible hydration of carbon dioxide to bicarbonate and proton and thereby contributes to acidification of extracellular milieu. Extracellular acidic pH facilitates tumor growth and progression. CA IX expression is upregulated by Hypoxia Inducible Factor-1 (HIF-1), which is negatively controlled by oxygen via wild type VHL protein and is also regulated by the cell redox state. We investigated the immunohistochemical pattern of distribution of CA IX in a small series (14 cases) of RCCs. CA IX expression was matched with the redox state of RCC, stratifying our series in relation to clinical and histopathological parameters, such as Fuhrman grade, staging, proliferation markers expression, and particularly, the presence of necrosis. Our results show for the first time the existence of a perivascular pattern of CA IX distribution in RCC. We also found a significant relationship between CA IX expression and the presence of necrosis. Tumors with higher CA IX expression exhibited higher degree of necrosis (p < 0.05). Notably, an almost significant relationship between the redox state and CA IX expression was detected in RCC patients with 5 years disease-free survival, most of them showing organ-confined disease. Tumors with lower redox state showed an algebraically higher degree of CA IX expression. On the contrary, tumors with higher redox state exhibited an algebraically lower CA IX expression (p = 0.057). The observed relationship of CA IX expression and necrosis suggests a role for CA IX in RCC. Further investigations are necessary to further establish the role of the redox state in regulation of CA IX expression in RCC.

Alpha-fetoprotein (AFP) is normally produced by primary hepatic neoplasms and germ cell tumors. There have, however, been reports of its production in cases of gastrointestinal tract adenocarcinoma. Gastric hepatoid carcinomas constitute a clinicopathological entity of recent acquisition and have certain common characteristics, which include the presence of hepatoid foci and frequent liver metastases, even in cases of early gastric cancer, and increasing serum AFP levels. In this study the case of one patient who underwent gastric resection and presented clinical, humoral, histological and immunohistochemical characteristics typical of hepatoid gastric carcinoma is reported. More biological studies, as well as precise criteria for pathological definition and therapy, are still necessary for a better understanding of this pathology.