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Computed tomography and angiography in pancreatic apudomas and cystadenomas.

During a 4-year period 17 patients with pancreatic apudoma and 3 patients with cystadenoma of the pancreas were admitted to this hospital. Computed tomography correctly located 3 of 4 insulinomas examined, while angiography revealed 4 of 8, which indicates that CT may replace angiography as the primary examination of these tumors, and possibly also other types of apudomas. When CT fails angiography may demonstrate a pancreatic tumor, suggesting angiography as a supplementary examination. In cystadenoma sufficient information was obtained at CT.

Adolescent↗

[Primary apudomas of the liver].

The literature data on primary liver apudomas with the discussion of their histogenesis, structure, endocrine activity and immunohistochemistry, 36 hepato- and cholangiocarcinomas are studied among which a group of poorly differentiated "atypical" tumours (9 cases) is distinguished. Large areas of endocrine-cell differentiation represented by solid, trabecular and alveolar structures consisting of small lymphocytoid cells or big cells with eosinophil cytoplasm and numerous sinusoid vessels were observed in these tumours. Cytoplasm of these cells contained argyrophylic granules in variable quantity. It is suggested that a certain part of primary liver apudomas is mistaking considered as poorly differentiated "atypical" hepato- or cholangiocarcinomas.

Aged↗

Primary liver apudoma.

In 1973 a liver tumour was classified as metastatic adenocarcinoma of unknown origin and the patient was treated with chemotherapy. A liver resection 10 years later revealed the tumour to be a primary apudoma. Such unusual localisation of apudomas may evidently have a better prognosis than other malignant liver tumours.

Adenocarcinoma↗

[Amyloid-forming apudoma of the breast].

A peculiar mammary gland tumour is described. Histological structures typical for apudomas of various level of differentiation were combined in the tumour. Apart from highly differentiated carcinoid-like areas, there were zones of a small-cell carcinoma corresponding to a poorly differentiated variant of apudoma. Deposits of amyloid were found in the tumor stroma, this being non-typical for mammary carcinoma. Amyloid was stained by Congo red and birefringent in a polarizing microscope. When differential diagnostics of mammary gland tumours is made, stromal amyloidosis in parallel to typical histological picture and specific histochemical reactions may play a role of an additional diagnostic symptom.

Amyloid↗

[Mucus-forming apudoma of the stomach].

Gastric apudoma (argyrophilic carcinoma) some cells of which are characterized by intensive production of intestinal mucosa is described. Endocrine granules were found in the cytoplasm of the tumor cells, including mucosa-producing ones, by means of diagnostic APUD-reactions (Grimelius method, staining with toluidine blue after acid hydrolysis, lead hematoxylin) and electron microscopy. In the opinion of the authors, mucosa production indicates the entodermal nature of the tumor which casts doubt on the conception of the common neuroectodermal origin of all apudomas.

APUD Cells↗

The APUD system and its apudomas.

As sensitive radioimmunoassays for the detection of polypeptide hormones are developed, the exciting discovery of a diffusely distributed system of interrelated endocrine cells has begun a new era of endocrinology. This system, although anatomically disassociated, is bound together by a number of common features such as its biosynthetic mechanism, histochemical and ultrastructural features, and embryologic origin (Table I). The most prominent feature, however, is their biosynthetic pathways for hormone production, from which the acronym APUD has been derived. These are the capacity for Amine Precursor Uptake such as DOPA and then subsequent Decarboxylation, resulting in the synthesis of bioactive amines or polypeptide hormones. Hyperplasias or neoplasms of these cells are defined as apudomas. In the last ten years a great deal of research has rapidly altered the original concepts of this system, especially in terms of its embryologic origin, physiologic interrelationships, classification, as well as the addition of many new APUD cell members. These will be reviewed, and the origin, diagnosis, and treatment of each recognized apudoma will be synthesized in light of its membership within the APUD system.

APUD Cells↗

[APUD cells and apudomas].

Synthesis of biologically active amines and peptides, and accumulation of them in the cytoplasm in the form of secretory granules of "neuroendocrine" type are among the most important characteristics of APUD cells. Apudomas, tumors consisting of cells with the properties of APUD elements, have many common morphological and functional features, although they are quite heterogeneous by clinical behavior and histogenesis. Histological diagnosis of apudomas requires the assessment of the endocrine function of the tumor cells for which histochemical and electron microscopic methods must be employed, as well as consideration of the clinical and biochemical indices of the hormonal activity of the tumors.

APUD Cells↗

[Cutaneous apudoma. Apropos of a case and review of the literature].

It has been suggested that Merkel Ranvier cells, generally considered as belonging to the Apud system, may be the origin of extremely rare skin tumors. The authors analyse the characteristics of an apudoma in connexion with a case, and compare their findings with those of 58 other cases reported in the literature. With light microscopy techniques, the differential diagnosis is essentially one of a non-differentiated primary or secondary carcinoma, or of a lymphosarcoma. Detection by electron microscopy of neurosecretory granules in the cell cytoplasm, the neuron-specific enolase activity, when this is detectable, the possibility of ectopic polypeptide secretions, and the evolution potential of the tumor, are all features warranting inclusion of this type of tumor in the category of apudomas.

APUD Cells↗

[Apudoma of the prostate].

Prostatic apudomas are represented by well-, moderately- and poorly differentiated variants. Histologic differentiation determines various functional properties of tumor cells. Tumor cells of well-differentiated apudomas produce serotonin, less frequently calcitonin, poorly differentiated ones produce only ACTH. Apud cells of moderately differentiated tumors, besides their main function to synthesize biogenic amines and hormones (serotonin, ACTH) possess immunoreactivity to epithelial membrane antigen, carcinoembryonal antigen and prostatic specific antigen.

APUD Cells↗

Combination chemotherapy of an APUDoma. With special reference to the therapeutic value of monitoring hormonal substances.

Investigations are presented on the occurrence of tumour products during combination chemotherapy of a 49-year-old female with an APUDoma metastatic to the liver. Calcitonin was demonstrated in high concentration in the tumour tissue. Serum calcitonin, serum histaminase and 5-HIAA in a 24-hour urine sample increased immediately after the administration of cytotoxic agents, falling subsequently below the pretreatment level. These findings indicate a therapeutic effect with lysis of tumour cells. Continuous determination of the three tumour substances showed an increase in these products before clinical suspicion of progression. Electron microscopic examination during the initial course disclosed the tumour to be an APUDoma. Autopsy failed to disclose a primary site outside the liver. Further autopsy findings were an adenoma of the thyroid and a chromofobe adenoma of the pituitary, thus assigning the patient to type 1 multiple endocrine neoplasia.

Amine Oxidase (Copper-Containing)↗

Effective streptozocin therapy for metastatic pancreatic polypeptide apudoma.

An apparently complete remission of metastases in the liver from a resected pure pancreatic polypeptide apudoma occurred following intra-arterial and intravenous administration of streptozocin to a patient in a family with multiple endocrine adenopathy, type 1. Plasma concentrations of human pancreatic polypeptide constitute an excellent marker system for the detection and assessment of tumor status before and after surgical and streptozocin therapy.

Adult↗

Pancreatic-polypeptide-producing apudoma of the liver.

A large hepatic excised from a 62-year-old man resembled a carcinoid tumor. No endocrine syndrome was present and an alternative primary source of tumor was found, despite an intensive search. The tumor cells were classified according to the type of electron-dense granules present: ACTH, gastrin (G), bombesin (P), and pancreatic polypeptide (PP) type granules were identified. Immunofluorescent staining with antibodies to several polypeptide hormones detected PP-containing tumor cells only. This rare tumor is therefore a PP-apudoma; possibly of intrahepatic bile duct origin.

Apudoma↗

A cutaneous APUDoma or Merkel cell tumor? A morphologically recognizable tumor with a biological and histological malignant aspect in contrast with its clinical behavior.

Clinical, microscopic, ultrastructural, and histochemical characteristics of a primary cutaneous tumor, identified as an APUDoma possibly arising from Merkel cells, are presented. The tumor can be diagnosed by means of routine histology. In some cases the argyrophylic staining technique can be helpful. The dermatological and histological aspects of this tumor suggest a highly malignant undifferentiated process. The biological behavior of this tumor, however seems to be of a low-grade malignancy. It is therefore important to recognize it from undifferentiated, highly malignant, mostly metastatic processes in the skin. There is also a summary of the clinical history and microscopic findings of identical tumors in 4 other patients.

Aged↗

Doxorubicin plus cisplatin in the treatment of apudomas.

Twelve patients with advanced apudomas--six with carcinoid tumors, two with chemodectomas, two with pancreatic islet cell tumor, and one each of medullary carcinoma of the thyroid and paraganglioma of unknown primary--were treated with a combination of doxorubicin 50 mg/m2 and cisplatin 50 mg/m2 every 3 to 4 weeks. Biochemical markers were present in 8 of the 12 patients. Five of the 12 patients (3 with carcinoid and 2 with chemodectomas) responded with more than 50% regression of tumor size measured as hypothetical area. Three others (two with islet cell tumors and one with carcinoid) had clinical and/or biochemical improvements. A median duration of response was 6 months. Nausea, vomiting, and alopecia were universal. Mild or moderate leukopenia was the most frequent toxicity. No sustained nephrotoxicity was seen. The combination of doxorubicin and cisplatin provides a new palliative therapy for patients with APUD tumors.

Adolescent↗

Clinically silent gross hypergastrinaemia from a multiple hormone-secreting pancreatic apudoma.

A patient is described who had a malignant pancreatic islet cell apudoma secreting corticotrophin (ACTH) and melanocyte-stimulating hormone (MSH), both of which were clinically active, and very large quantities of immunoreactive gastrins, which were biologically active but clinically silent (normal gastric acid secretion and no peptic ulceration). The presence of parietal cell antibodies, with no increase in the plasma concentrations of hormones which can inhibit gastric acid secretion (secretin, GIP and VIP), suggests that many of the of the parietal cells may have been blocked by the autoantibodies.

Adenoma, Islet Cell↗

Liver transplantation for primary and secondary hepatic apudomas.

Four patients underwent liver transplantation in the Cambridge/King's College Hospital programme for malignant primary and secondary apudomas, secreting various peptide hormones and uncontrollable by standard treatment techniques. After transplantation all patients had excellent symptomatic relief and specific peptide hormone levels fell to normal ranges. Two patients remain alive and well after 38 and 22 months, the latter with recurrence of slight tumour-related symptoms and elevation of the specific secretory product. The other two patients died from chronic graft rejection 7 and 8 months after transplantation.

Adult↗

Controversies in surgical therapy for APUDomas.

Location of gastrinomas by means of portal venous sampling is a technique in which venous blood from various sites in the portal system around the pancreas and duodenum is obtained and assayed for gastrin levels. A gradient of 50% or greater compared to systemic gastrin levels from a given location regionally identifies the site of gastrin overproduction, thereby locating the tumor. The only area in which venous sampling may help, in the authors' opinion, is in the small subset of patients who have occult gastrinoma not imaged with any other modality, in the body or tail of the pancreas that cannot be found with intraoperative ultrasound or palpation. It is considered that a secretin angiogram is equally effective and is a simpler procedure. Similarly, in insulinoma regional location of the tumor by means of a calcium angiogram has eliminated the usefulness of portal venous sampling. Controversial areas of surgical treatment of APUDomas often reflect a balance between the risks and benefits of aggressive surgery, as data to support an aggressive surgical approach to obtain improved survival often do not exist. For example, if patients with occult MTC can undergo cervical reexploration with minimal or no morbidity the potential benefit of removing malignant disease, warrants this approach. Similarly, if patients with MEN-1 can be explored safely with resection of pancreatic and duodenal tumors, then this position can be defended. On the other hand, if a subgroup of patients with MEN-2 and pheochromocytomas can be spared bilateral adrenalectomy without compromising their long-term outcome in terms of disease-free survival, then this conservative approach is warranted.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Gland Neoplasms↗

[Liver apudoma simulating cystic liver].

A 36-year-old man in otherwise good general condition and with completely normal laboratory results suffered from right upper abdominal pain. Hepatomegaly was diagnosed as due to cystic liver disease after ultrasound, computed tomography and magnetic resonance imaging. Recurrent abdominal pain continued over several months. Open liver biopsy eventually revealed trabecular-tubular carcinoma (APUDoma). Silver reaction was positive in many tumour cells. Electronmicroscopy demonstrated membrane-bound granules typical for endocrine cells. Immunohistological examinations of various hormones and of neurone-specific enolase were negative, but repeatedly measured high serum levels of pancreatic polypeptide and of beta-HCG nonetheless suggested an endocrine tumour. This case demonstrates that nonparasitic cystic changes in the liver, especially multiple ones, should have a firm diagnosis established by invasive means. Endocrine tumours can be mistaken for polycystic liver disease.

Adult↗