1/27. Gastroenteropancreatic neuroendocrine tumor metastases to the thyroid gland: differential diagnosis with medullary thyroid carcinoma.neuroendocrine tumors (NET) of the thyroid gland are rare. Apart from medullary thyroid carcinoma (MTC), metastases of gastroenteropancreatic (GEP) NET may also occur. Features of six patients (five men, one female: age range, 39-67 years) with thyroid metastases from a GEP-NET are described. Thyroid metastases were bilateral in all patients and were associated with enlarged neck lymph nodes in five. In four cases, the thyroid tumor was either the first sign of the disease (n = 2) or was an isolated site of recurrence (n = 2). The tumors were well (n = 3) or poorly differentiated (n = 3). Five tumors for which the primary site could be determined corresponded to foregut-derived tumors (3 lungs, 1 thymus and 1 pancreatic NET). One tumor demonstrated calcitonin (CT) production as shown by immunohistochemistry and elevated plasma CT levels. However, the disease history and the clinical features strongly favored a metastasizing GEP-NET. No tumoral RET proto-oncogene mutation was found in this patient. The differential diagnosis between metastatic GEP-NET and MTC is crucial because prognosis, work-up, and treatment differ greatly.- - - - - - - - - - ranking = 1keywords = neuroendocrine (Clic here for more details about this article) |
2/27. Angiomatoid neuroendocrine carcinoma of the thymus: report of a distinctive morphological variant of neuroendocrine tumor of the thymus resembling a vascular neoplasm.Three cases of primary thymic neuroendocrine tumors characterized by prominent angiomatoid features that resembled a vascular neoplasm are presented. The patients were all men between 52 and 59 years of age who presented with chest pain and shortness of breath attributable to a large anterior mediastinal mass. The lesions ranged in size from 6 cm to 15 cm in greatest diameter, and were grossly soft and well circumscribed, but not encapsulated. The cut surface was remarkable for multiple blood-filled cyst-like spaces admixed with focal solid, hemorrhagic areas. Histologically, the tumors contained multiple cystically dilated spaces filled with blood which imparted the lesion with a striking angiomatoid appearance. The walls of the cysts were lined by a monotonous proliferation of round to oval cells with distinct cell borders, round central nuclei, and abundant eosinophilic cytoplasm. Mitotic activity was present in all cases and varied from 3 to 8 mitoses per 10 high-power fields. Immunohistochemical studies performed in two cases showed positivity of the tumor cells for keratin, Leu 7, and synaptophysin, and focal chromogranin positivity in one. Follow-up information obtained in two patients showed that both had died of tumor 4 and 8 years after initial diagnosis. The present cases show an unusual morphological appearance of thymic neuroendocrine tumors that may be mistaken for a vascular neoplasm. Immunohistochemical stains may be of importance in such instances in arriving at the correct diagnosis.- - - - - - - - - - ranking = 2.5keywords = neuroendocrine (Clic here for more details about this article) |
3/27. Thymic carcinoid and parathyroid hyperplasia detection with 99mTc-MIBI men type 1.We report a case of a 35-year-old male, with a history of diarrhea, renal lithiasis with frequent expulsions of calculus and hypercalcemia during the last 2 years. The patient was studied and diagnosed with a multiple endocrine neoplasia type I (MEN I), familiar (mother with MEN I). A scintigraphic study with 99mTc-MIBI was performed in order to localize hyperfunctioning parathyroid glands because of biochemical diagnosis of primary hyperparathyroidism. Double phase 99mTc-MIBI scan detected one hyperfunctioning parathyroid gland and a large anterior mediastinal mass. Subsequent, plain radiograph and CT of the chest showed a soft-tissue mass in that localization. Punch biopsy of the lesion guided by CT revealed malignant cells of neuroendocrine tumor. The tumor was removed and histologically confirmed as a carcinoid within a thymus in a MEN type I syndrome. MEN I patients can benefit from the examination with this agent which can potentially localize not only parathyroid endocrine pathology but also unknown associated tumors.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
4/27. Transesophageal echocardiographic findings of an intracavitary cardiac metastasis from a neuroendocrine thymic carcinoma.This case report presents the unusual characteristics of a neuroendocrine thymic carcinoma that probably has metastasized to the left side of the interatrial septum from a primary thymic site.- - - - - - - - - - ranking = 1.25keywords = neuroendocrine (Clic here for more details about this article) |
5/27. Small cell neuroendocrine carcinoma of the thymus complicated by Cushing's syndrome. Report of a 58-year-old woman with a 3-year history of hypertension.A 58-year-old woman with a history of Cushing's syndrome for three years presented with a mediastinal mass and received the diagnosis of small cell neuroendocrine carcinoma of the thymus invading the pericardium. On immunohistochemical study, the neoplastic cells reacted with antibodies against cytokeratin, epithelial membrane antigen, neuron-specific enolase, chromogranin, synaptophysin, and ACTH. Clinicopathologic findings of this rare case of ectopic adrenocorticotropic hormone (ACTH) syndrome are discussed with a literature review.- - - - - - - - - - ranking = 1.25keywords = neuroendocrine (Clic here for more details about this article) |
6/27. Lipid-rich carcinoid tumor of the thymus gland: diagnosis by fine-needle aspiration biopsy.In this report we describe the cytologic features of an unusual thymic carcinoid tumor containing prominent cytoplasmic lipid vacuoles that was diagnosed by fine-needle aspiration biopsy. The tumor presented as a presternal subcutaneous mass in an 81-yr-old female, with a contiguous mediastinal mass on computed tomography. The cytomorphologic features included numerous discohesive cells with eccentric, round to oval nuclei, granular chromatin, and scant cytoplasm containing numerous intracytoplasmic, clear vacuoles. The neoplastic cells were reactive for neuroendocrine markers by immunocytochemistry and showed reactivity of the intracytoplasmic vacuoles with an oil red-O stain for neutral lipid. Ultrastructural examination confirmed the presence of intracytoplasmic lipid vacuoles and neurosecretory granules. Subsequent surgical excision confirmed the diagnosis. We believe this to be the first report describing these features in a primary thymic carcinoid tumor. The differential diagnosis of mediastinal tumors with clear-cell features and cytoplasmic vacuolization is also discussed.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
7/27. Malignant thymic carcinoid is not prevented by transcervical thymectomy in multiple endocrine neoplasia type 1.multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant tumour syndrome. It is characterized by primary hyperparathyroidism, pituitary neoplasia and foregut lineage neuroendocrine neoplasia. Malignant thymic carcinoid tumours are an uncommon but important manifestation of MEN 1. Transcervical thymectomy is often advocated as prophylaxis against thymic carcinoids, although there is a paucity of evidence to support the efficacy of this procedure. This is the first report of a malignant thymic carcinoid occurring in an MEN 1 patient following prior parathyroidectomy and transcervical thymectomy. It is concluded that transcervical thymectomy does not reliably provide prophylaxis against thymic carcinoid.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
8/27. Paraneoplastic Cushing's syndrome associated to locally advanced thymic carcinoid tumor.BACKGROUND: Thymic carcinoid is a frequent cause of Cushing's syndrome due to ectopic adrenocorticotropin secretion. histology and immunohistochemistry allow differential diagnosis from other epithelial thymic tumors, such as thymomas and thymic carcinomas. The term used to name this tumor is confusing, since it is a malignant neuroendocrine neoplasm, and therapeutic approaches need to bear that in mind. CASE REPORT: Unlike most cases of thymic carcinoid associated to Cushing's syndrome that had distant metastases at diagnosis, we report a 50-year-old male who presented with Cushing's syndrome and was diagnosed with thymic carcinoid without distant metastases. Multimodal treatment with surgery, radiotherapy and chemotherapy (cisplatin plus etoposide) induced a complete clinical and biochemical remission lasting for 46 months.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
9/27. Thymic carcinoma with brain metastasis mimicking meningioma.Thymic carcinoma is a rare malignancy, which differs from thymoma in that it displays histopathologically malignant features, extensive local invasion, and a substantial potential for metastasis, predominantly to the liver and kidney and rarely to the central nervous system. Most of cerebral metastases are the intraaxial tumor, whereas extraaxial masses mimicking meningioma are extremely rare. A 32-year-old woman who had been treated for thymic carcinoma with multiple bone metastasis including spine and ribs was referred to the neurosurgery department with a diagnosis of right temporal extraaxial mass. magnetic resonance imaging (MRI) revealed an extraaxial tumor with hemorrhage along the medial margin of tumor. A craniotomy was performed to remove the mass that was located extraaxially. Histopathological and immunohistochemical examination revealed undifferentiated thymic carcinoma with neuroendocrine differentiation. The patient recovered from the preoperative deficits, and local irradiation of 50 Gy was performed. This paper will examine briefly the radiolographic and pathologic characteristics of this unusual lesion. Although extraaxial thymic carcinomas are rare, they should be considered in the radiographic differential diagnosis of dural-based lesions, especially for patients with history of thymic lesions.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
10/27. Hepatoid thymic carcinoma: report of a case.We describe the clinicopathologic findings in a so far unrecognized thymic tumor. The tumor occurred in a 70-year-old woman with respiratory distress but neither myasthenia gravis nor other symptoms. Metastases or another primary tumor were absent. The well-circumscribed neoplasm was located in the thymic region, measured 18 x 12 x 8 cm, and showed a homogeneous, tan-colored, soft cut surface. By histology, the tumor lacked a true capsule and a lobular growth pattern, was almost devoid of stroma, and infiltrated among remnant thymus lobules. The polygonal tumor cells formed solid sheets, trabeculae, or occurred as single cells that resembled hepatocytes. Proliferative activity was low. Portal structures, sinuses, and bile were absent as were areas of conventional thymoma, adenocarcinoma, or germ cell tumor. The tumor expressed cytokeratins 7 and 19, alpha1-antitrypsin, alpha1-antichymotrypsin, and hep-Par-1. Alpha-fetoprotein (AFP), human beta-chorionic gonadotropin (beta-HCG), placental alkaline phosphatase, CD5, CD30, CD31, CD34, CD45, CD68, CD99, S-100, HMB45, desmin, actin, or neuroendocrine markers were not expressed, and intratumorous CD1a or TdT immature T cells were absent. AFP was repeatedly undetectable in the blood. Mediastinal tumor recurrence was detected 6 months after surgery. Following radiochemotherapy, the patient has remained free of disease for 26 months. We conclude that this tumor is a thymic carcinoma (WHO type C thymoma). A diagnosis of hepatoid yolk sack tumor appears unlikely considering absence of a bona fide germ cell component, lack of AFP expression, and the patient's female gender. Because of its morphologic and immunohistochemical features, we propose the term "hepatoid thymic carcinoma" for this new type of thymic carcinoma.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
| | Next -> |