1/6. Neuroendocrine carcinoma of the uterus.Neuroendocrine carcinomas of the cervix and endometrium were reviewed. They have been variously designated as carcinoid, argyrophil cell carcinoma, apudoma, small cell carcinoma, oat cell carcinoma, endocrine carcinoma, and neuroendocrine carcinoma, the last-mentioned term being preferred in this chapter. Adenocarcinomas with neuroendocrine cells are occasionally encountered in the cervix and endometrium. It is generally questioned whether they should be included in the spectrum of neuroendocrine carcinomas, although differential diagnosis between some such tumors of the gastrointestinal tract and neuroendocrine carcinoma is reported to be difficult. Since the majority of neuroendocrine carcinomas of the cervix are highly aggressive, it is important to establish the neuroendocrine nature in the cervical carcinomas. In addition to the characteristic histologic features and argyrophil stainability, immunohistochemical demonstration of several neuroendocrine markers may be helpful in diagnosing neuroendocrine carcinoma of the cervix. Ultrastructural demonstration of neurosecretory granules is almost decisive in establishing the tumor's neuroendocrine nature, but it is not applicable in all cases. Neuroendocrine carcinomas of the cervix have been treated by surgery, radiation therapy, and chemotherapy, but optimal treatment methods have not yet been established because of the rarity of the tumor. Finally, we have described a typical neuroendocrine carcinoma of the cervix and reported some data regarding its experimental study.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/6. apudoma and subcorneal pustular dermatosis (Sneddon-Wilkinson disease).The subcorneal pustular dermatosis (SPD) is a rare dermatosis. IgA monoclonal gammapathy is the most frequently associated disease with the SPD. We report a case of SPD in a patient with metastatic apudoma, an association not previously described. The rare nature of both diseases suggests that this association is not fortuitous.- - - - - - - - - - ranking = 0.5keywords = nature (Clic here for more details about this article) |
3/6. Cyclical release of vasoactive intestinal polypeptide (VIP) from a pancreatic islet cell apudoma.A patient is described who presented with the classical symptomatology and profound electrolyte disturbance of the Verner-Morrison syndrome due to a pancreatic apudoma secreting vasoactive intestinal polypeptide (VIP). diagnosis was confirmed by plasma VIP as measured by a radio-immunoassay technique now available. It is suggested that the cyclical nature of the symptoms in this case was due to cyclical release of VIP from the tumour in response to an unknown stimulus. perfusion studies confirmed the excess secretory state of water, sodium and chloride in the small intestine. Symptoms were completely abolished by surgery and the progress is being monitored by means of serial plasma VIP estimations to detect any early recurrence of metastatic disease.- - - - - - - - - - ranking = 0.5keywords = nature (Clic here for more details about this article) |
4/6. iodine-131 MIBG scintigraphy of neuroendocrine tumors other than pheochromocytoma and neuroblastoma.Metaiodobenzylguanidine (MIBG) locates most pheochromocytomas and neuroblastomas. The tracer is concentrated in intracellular storage vesicles by an active process. Many other neuroendocrine tumors of the amine precursor uptake and decarboxylation (APUD) series have hormonal storage vesicles and, thus, the potential to take up [131I]MIBG. A variety of neuroendocrine tumors in 57 patients were studied 1, 2, and 3 days after 0.5 mCi [131I]MIBG. Views from skull to pelvis were obtained. Results of MIBG scans were compared with all available imaging modalities (including plain radiography, liver scan, ultrasound, computed tomography, and angiography) and surgical exploration. The neuroendocrine nature of the tumor was determined by histology, immunohistochemistry, electron microscopy, and the assay of appropriate biogenic amines and peptide hormones. Results were (positive/total cases): carcinoids (four of ten), nonsecreting paragangliomas (three of three), sporadic medullary carcinomas of the thyroid (MCT) (one of five), familial MCT (one of 26), chemodectomas (two of five), oat cell carcinomas (zero of four), choriocarcinoma (one of one), atypical schwannoma (with storage granules) (one of one), Merkel cell skin cancer (one of one), islet cell carcinoma (zero of one). We conclude that a wide range of neuroendocrine tumors show [131I]MIBG uptake; tumors other than pheochromocytomas and neuroblastomas are less often seen scintigraphically, but in certain cases (e.g., carcinoid and nonsecreting paragangliomas) scintigraphy may be useful in depicting the extent and location of disease and may indicate therapeutic potential. iodine-131 MIBG shows promise in the diagnosis and staging of tumors of varied types.- - - - - - - - - - ranking = 0.5keywords = nature (Clic here for more details about this article) |
5/6. Merkel cell tumor. A chemosensitive skin cancer.The clinical courses of six patients treated with cytotoxic chemotherapy for recurrent Merkel cell tumor of the skin are reported. All patients experienced prompt clinical responses to chemotherapy (five complete response [CR], one partial response [PR]) and three patients (50%) have achieved long-term disease-free remission. The report highlights (1) the aggressive nature of Merkel cell skin cancer, (2) the highly chemosensitive nature of the disease, and (3) some practical problems in administering chemotherapy to elderly patients.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/6. APUD system neoplasms in renal transplant patients.Apudomas are uncommon neoplasms composed of neuroendocrine cells. They include carcinoid tumors, islet cell tumors, and small cell lung carcinoma. We found six cases of apudomas in a series of 1028 renal transplants from three medical centers (0.58%). One of these had been reported in 1976. The cases included a carcinoid tumor of a Meckel's diverticulum discovered and removed prior to transplantation, with no evidence of recurrence 9 years later. A small cell lung carcinoma was discovered 40 months after renal transplantation, with a fatal outcome 6 months later. Four clinically occult apudomas were found at autopsy, including one gastric and one bronchial carcinoid tumor, one multicentric pancreatic islet cell neoplasm, and one case of multiple ileal carcinoids. With the exception of the small cell lung cancer, none of the apudomas was clinically significant, and none was associated with carcinoid or other paraneoplastic syndrome. These cases illustrate the difficulty of diagnosis of apudomas in patients with renal failure and the usually benign nature of these tumors despite the administration of potent immunosuppressive agents.- - - - - - - - - - ranking = 0.5keywords = nature (Clic here for more details about this article) |