Biomedical subjects
Publications and source records attributed to G K Nguyen.
Fine needle aspiration biopsy for cytologic evaluation of mass lesions of the kidney, renal pelvis and adrenal is a safe economic and accurate diagnostic procedure. Tumors and inflammatory or degenerative lesions arising from these organs have characteristic cytologic features permitting their correct identification in the majority of cases.
Five cases of histologically confirmed grade 1 papillary transitional cell carcinoma of the renal pelvis investigated by needle aspiration biopsy cytology were reviewed. In all cases the needle aspirates were hypercellular. Abundant benign-appearing urothelial cells in thick clusters, in small aggregates, and singly were seen in two cases. Numerous single and loosely aggregated urothelial cells with cytoplasmic extensions and slightly pleomorphic nuclei were noted in one case. In two patients numerous urothelial fragments of variable sizes showing defined cytoplasm and mildly nuclear pleomorphism were the main cellular findings.
Two cases of histologically, immunohistochemically, and ultrastructurally confirmed collecting duct carcinoma of the kidney (CDCK) with positive urine cytology are reported. The patients' urine sediments showed malignant glandular cells in sheets with defined, variable, granular cytoplasm and oval, hyperchromatic nuclei containing micro- or macronucleoli. The cytologic differential diagnosis of CDCK is briefly discussed.
To determine the cytodiagnostic accuracy rate and pitfalls of Hashimoto's thyroiditis (HT), the files and smears prepared from the thyroid needle aspirates of 146 patients with suspected HT and/or clinically and serologically confirmed HT were reviewed. Of those patients, 105 presented with a diffuse and rubbery thyroid enlargement, and 41 with one or two prominent nodules. For the first group (105 patients), the needle aspiration biopsy (NAB) was performed on one or two thyroid lobes during their initial endocrinologic consultation, and for the second group (41 patients), the NAB was performed on and around the predominant nodules that were found either at initial physical examination or during the patients' routine follow-ups. In 134 cases, a cytodiagnosis of HT was made on the first NAB. Among the 41 patients with a prominent thyroid nodule, a thyroid neoplasm was suspected clinically in four because their thyroid nodules increased in size. In the other 12 patients, a cytodiagnosis of follicular neoplasm (FN) was made in five cases, and a Hürthle cell tumor (HCT) was diagnosed or suspected in seven patients. All 16 patients had thyroid surgery, and a HT was histologically confirmed in all cases. In the first four patients, no tumor was found. Among five patients with a cytodiagnosis of FN, one had a hyperplastic follicular cell nodule (HFCN), two had follicular adenomas, and two had papillary carcinomas of follicular variant. For the seven patients with a cytodiagnosis of HCT, HCT was confirmed in three, three were found to have hyperplastic Hürthle cell nodules (HHCN), and one showed a benign colloid nodule with Hürthle cell changes and remote hemorrhagic necrosis. It is concluded that NAB is highly sensitive in diagnosing HT, with a diagnostic accuracy rate of 92% by the first biopsy attempt. The cytologic differential diagnosis between an HFCN and a follicular neoplasm and between an HHCN and an HCT is impossible in some cases.
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Forty-two histologically confirmed cases of pancreatic cystic lesions with cytologic evaluation by needle aspiration biopsy (NAB) were reviewed. There were 21 inflammatory pseudocysts (IPC), nine mucinous cystic neoplasms (MCN), six microcystic serous adenomas (MSA), one macrocystic serous adenoma, and five papillary solid and cystic neoplasms (PSCN). Correct cytodiagnosis was made in all cases of IPC and MCN. The contents of IPCs were characterized by turbid or blood-tinged fluid containing cellular debris, numerous foamy macrophages, and other inflammatory cells. There were few or no epithelial lining cells. The aspirates from MCNs showed gelatinous mucoid material containing mucus-secreting cells that were present singly, in clusters, or in sheets. Depending on the individual case, benign or malignant columnar cells, or an admixture of these cells, were present in a mucinous background. The preoperative needle aspirates of five MSAs were acellular. In one case of MSA and in one example of macrocystic serous adenoma, small monolayered sheets of benign cubic epithelial cells were seen in the needle aspirates. Similar cytologic findings were noted in the materials obtained by intraoperative NAB performed under direct vision of the aforementioned five MSAs. Difficulties were encountered in typing three PSCNs that yielded in NAB cells resembling those of an islet cell tumor. They were diagnosed as low-grade neoplasms (PSCN vs. islet cell tumor). In two other patients, a cytodiagnosis of PSCN was correctly made as the NAB revealed monomorphic tumor cells wrapping around small capillary blood vessels.
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The ultrastructure of lung parenchyma of CBA/J mice 1 year after 14 Gy X irradiation was studied by transmission electron microscopy (TEM) and compared with the ultrastructure of age-matched control mice. The irradiated mice had received an injection of colloidal carbon just prior to death to identify patent capillaries. Regions containing carbon were compared by TEM with apparently nonperfused areas lacking carbon. The interalveolar interstitial tissue and the capillary endothelium were not different ultrastructurally in perfused and nonperfused regions. There were no appreciable differences between irradiated and unirradiated lung, except for small, infrequent focal areas with a slight increase in the number of collagen fibers. The ultrastructural examination did not reveal any lesion which might have been missed in the preliminary light microscope studies, which confirms that the lack of perfusion in CBA/J mice which have an appreciable respiratory functional deficit in the late phase is not due to the loss of patent capillaries or to fibrosis of the alveolar wall. It was concluded that the lesion must be at the "pre-capillary" level, probably damage to or loss of small blood vessels.
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A case of histologically and ultrastructurally confirmed carcinoid tumor of the renal pelvis is reported. The patient's urine sediment showed a few groups and sheets of polygonal malignant cells with scant cytoplasm and oval nuclei displaying chromatin clumping and micronucleoli.
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Cervical scraping smears from two cases of histologically confirmed adenoma malignum of the uterine cervix were reviewed. In one case, several irregular sheets of benign-appearing glandular cells with slightly enlarged nuclei, conspicuous nucleoli, and clear cytoplasm were found. In the other case, in addition to sheets of benign-appearing glandular cells, there were clustered malignant glandular cells with prominent nucleoli. The sheets of benign-appearing glandular cells in both cases displayed wispy cytoplasmic extensions or "tails." Cytologic differential diagnosis with other glandular lesions of the cervix such as clear cell carcinoma, microglandular hyperplasia, diffuse laminar glandular hyperplasia, tubal metaplasia, and well-differentiated invasive or in situ adenocarcinoma is briefly discussed.
A 64-year-old woman presented initially with a metastatic spindle-cell sarcoma of the lung of unknown primary. She suddenly died nine months later from hemopericardium with cardiac tamponade caused by partial hemorrhagic necrosis of pulmonary artery trunk sarcoma.
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BACKGROUND: Thyroid carcinomas historically have been divided into two groups according to their presumedly separate embryonic origins: those of neuroectodermal derivation (parafollicular or medullary carcinoma [MCT]) and those of foregut endodermal origin (follicular and papillary carcinomas). The validity of this concept has been questioned by the recognition that some MCT may show immunocytochemical and ultrastructural evidence of follicular components, and display features of follicular function (e.g., organification of iodine, immunoreactivity for thyroglobulin). METHODS: A 14-year-old boy presented with the physical features of multiple endocrine neoplasia type 2-B (MEN 2B) and a thyroid mass. His thyroid lesion was studied by light microscopy; electron microscopy; immunohistochemistry using antisera to calcitonin, thyroglobulin, and other peptides; and in situ hybridization. RESULTS: The tumor was identified as an MCT by light microscopy. It stained positively with calcitonin, thyroglobulin, chromogranin, neuron-specific enolase, and serotonin. At the ultrastructural level, the tumor cells contained numerous neurosecretory granules and showed evidence of follicular differentiation (luminal microvilli, follicle formation, and tight junctions), suggesting a dual neuroendocrine and follicular differentiation. CONCLUSIONS: The morphologic findings suggest that a small number of MCTs arise from a common stem cell (possibly the ultimobranchial body) that may give rise to both MCT and follicular carcinoma. This patient and patients in similar cases documented in the literature challenge the classic concept of separate pathways of embryogenesis for these two cell types.
A case of small-cell anaplastic carcinoma of the prostate, occurring in an 82-year-old man with prior prostatic adenocarcinoma, is reported. The exfoliated tumor cells in the urine were seen singly or in loose aggregates with molding. They showed scant cytoplasm and slightly pleomorphic, hyperchromatic nuclei with inconspicuous nucleoli. By electron microscopy the tumor consisted of primitive epithelial cells without glandular or neuroendocrine differentiation. The tumor pursued a highly aggressive course, and the patient died of metastatic disease 4 mo after the diagnosis.
A case of histologically and ultrastructurally confirmed acinar-cell carcinoma of the pancreas examined by needle aspiration cytology is reported. The aspirate showed isolated and loosely clustered cells with variable granular cytoplasm, and central or eccentrically located oval hyperchromatic nuclei displaying prominent nucleoli, suggesting a pancreatic neuroendocrine tumor. Numerous intracytoplasmic zymogen granules and several microtubules within cisternae of rough endoplasmic reticulum (MCRER) were found by electron microscopic study of metastatic tumor tissue. Cytodiagnostic pitfalls of this rare pancreatic cancer are discussed as well as the diagnostic value of MCRERs.
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