Showing papers by "Bernd W. Scheithauer published in 1982"

Primary thymic carcinomas.

Abstract: Within a 75-year period, 20 patients with primary nonteratomatous carcinomas of the thymus were seen at the Mayo Clinic. Fourteen were males and six were females, with a mean age of 48 years. Thirteen of the lesions were classified as poorly differentiated or spindling squamous cell carcinomas. One neoplasm was a sarcomatoid carcinoma, and two showed both squamous cell and neuroendocrine ultrastructural features. The remaining four tumors had both light- and electron-microscopic features of neuroendocrine carcinomas. In all 20 patients, careful clinical and pathologic examinations, including autopsy in fatal cases, excluded malignant lymphomas and metastasis to the thymus from epithelial tumors in other anatomic sites. Thirteen patients underwent surgery, with or without postoperative radiotherapy; of these, one was alive and apparently disease-free 43 months after diagnosis. There were two operative deaths. The remaining patients received primary radiotherapy or chemotherapy, or both. The mean survival of the 16 patients who died (excluding operative deaths) was 18.7 months for the 14 patients with tumors of squamous cell differentiation and 36.0 months for the two patients with pure neuroendocrine carcinomas. Among patients with squamous cell carcinoma, 11 developed metastases to lungs, liver, bones, adrenal glands, or extrathoracic lymph nodes; nine of these died of massive local growth within the mediastinum. Among patients with neuroendocrine carcinomas, two of four patients died of local growth within the mediastinum; one of these also had metastases to the liver and adrenal glands. One patient with oat cell carcinoma was alive with residual thoracic tumor and cervical lymph node metastasis 18 months after diagnosis.

Clinical and pathological study of meningiomas of the first two decades of life

Abstract: The clinical features and pathological materials of 51 cases of histologically verified meningiomas in patients under 21 years of age were reviewed. The age range was 7 to 20 years, with the majority of cases being clustered in the second decade of life. There was virtually a 1:1 sex ratio, with 26 females and 25 males. Thirty-eight patients had intracranial meningiomas, three had intraorbital tumors, and 10 had intraspinal tumors. Twelve patients (24%) had neurofibromatosis. Twenty patients (39%) had tumor recurrence. The cases were subdivided into five histological categories: meningotheliomatous, fibrous, transitional, psammomatous, and papillary. In each case, the clinical course was correlated with histological subtype. The 15-year survival rate in patients with intracranial meningiomas of all types was 68%. Factors adversely affecting survival included infratentorial location, papillary histology, and evidence of brain invasion.

Oat-cell carcinoma of the thymus

Abstract: Oat-cell carcinoma of the thymus gland is exceedingly rare as a primary lesion, and only a few cases have been reported. We report a case in which a neoplasm interpreted as an oat-cell carcinoma was intimately associated with and arose in transition from a carcinoid tumor of the thymus. Ultrastructural features of this lesion were unusual compared with previous descriptions of thymus neuroendocrine neoplasms.

Massive hyperplasia of testicular adrenal rests in a patient with Nelson's syndrome.

Abstract: The case of a 23-year-old man with Nelson’s syndrome is presented. He had undergone bilateral adrenalectomy at age 15 years for Cushing’s syndrome. Postoperatively, his cushingoid features resolved; however, 13 months later, he became hyperpigmented and showed radiographic evidence of sellar enlargement and midline expansion of the sellar floor. In 1972, he received radiation therapy to the pituitary gland. He underwent transsphenoidal hypophysectomy in 1974 and 1975 for recurrent pituitary adenoma, and recurrent Cushing’s syndrome developed concomitantly with bilateral firm testicular masses in 1978. External scanning with NP-59 localized steroid production to the testes, and bilateral orchiectomy was performed. Immunohistochemical studies of the pituitary tumor confirmed the presence of adrenocorticotropic hormone, and morphologic and ultrastructural examinations of the testes supported the adrenal nature of the testicular tumors.

Thrombosed arteriovenous malformations of the brain: An important entity in the differential diagnosis of intractable focal seizure disorders

Abstract: ✓ Thrombosed arteriovenous malformations (AVM's) in patients with no previous history of hemorrhage are uncommon but benign lesions that present with clinical and radiographic findings which are often indistinguishable from those of other mass lesions, particularly low-grade gliomas. The authors report seven cases of thrombosed AVM's presenting as intractable seizure disorders in which the radiographic studies had suggested a low-grade glioma. All seven patients are now seizure-free 2 to 40 months postoperatively. The importance of surgical exploration in the management of such patients is emphasized. A review of 32 cases reported in the literature is presented. The reasons why angiography may fail to demonstrate an AVM, and the possible etiologies for the spontaneous thrombosis of an AVM are discussed.

Adamantinoma of bone. An electron microscopic and immunohistochemical study.

Abstract: Adamantinoma of bone is a rare tumor, and fine structural analysis has been done in only a few cases. We report four cases studied by electron microscopy and immunohistochemical methods. Ultrastructural evaluation revealed a characteristic constellation of features, including intracellular bundles of type I microfilaments, moderate numbers of evenly dispersed mitochondria, scattered profiles of rough endoplasmic reticulum, occasional Golgi bodies and lysosomes, and scattered glycogen particles. Microvillous processes and desmosomes were identified in all tumors. Well-formed basement membranes enveloped cell clusters but did not surround individual cells. Intercellular basement membrane-like material also was found focally in pools. Ultrastructural features of endothelial differentiation, including Weibel-Palade bodies, micropinocytotic vesicles, and tight junctions, were not identified. Immunoperoxidase stains for coagulation factor VIII (von Willebrand factor) and blood group antigens were negative, whereas similar stains for keratin were positive. Our findings strongly suggest that adamantinoma is a neoplasm expressing definite epithelial, rather than endothelial, characteristics.

The spectrum of inappropriate pituitary thyrotropin secretion associated with hyperthyroidism.

Abstract: Two patients with overproduction of thyroid-stimulating hormone (TSH) are described. The first patient, a 25-year-old man with recurrent hyperthyroidism, had a pituitary adenoma and highly elevated levels of TSH. While the patient was receiving 0.3 mg of thyroid daily, and basal TSH level was 161 microM/ml. Despite an increase in the thyroid hormone therapy, serum TSH levels remained elevated. The administration of thyrotropin-releasing hormone (TRH) or dexamethasone resulted in no changes in TSH level. The second patient was an 18-year-old man who had inappropriately elevated levels of TSH 3 months after radioiodine therapy for hyperthyroidism. A gradual increase in thyroid hormone replacement therapy decreased the serum TSH levels from 250 to 14.8 microM/ml. The administration of TRH led to huge increases of TSH. Dexamethasone inhibited basal TSH but not TRH-stimulated TSH levels. The overproduction of TSH was attributed to autonomous, neoplastic secretion in the first case and to partial, selective pituitary thyrotroph resistance to thyroid hormone in the second.

Primary pulmonary leiomyosarcomas. A light and electron microscopic study.

Abstract: Fewer than 100 cases of primary leiomyosarcoma of the lung have been reported, few of which have been studied by electron microscopy. We performed clinicopathologic studies, including fine structural analysis, of two such cases. Their ultrastructural features differed in part from those of other smooth-muscle tumors, which may help exclude other malignant pulmonary lesions from the differential diagnosis.

Gaucher's disease and glioblastoma multiforme in two siblings: a clinicopathologic study.

Abstract: The clinical and pathologic features of two brothers with the adult form of Gaucher's disease, both of whom developed cerebral glioblastoma multiforme, are presented. Neither patient had a long-standing neurologic disorder, and morphologic evidence of nervous system glucocerebroside storage was not seen. Despite the known increased incidence of malignancy in Gaucher's disease, a review of the literature and of sixty-two Mayo Clinic cases of adult onset Gaucher's disease revealed only one other instance of the association with glioma. The significance of the relationship is unknown.