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Z W Baloch

Publications and source records attributed to Z W Baloch.

At least 37 records · Page 2Linked to original sources
PubMed2000

Primary mucoepidermoid carcinoma and sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid gland: a report of nine cases.

Mucoepidermoid carcinoma is a rare primary thyroid tumor with indolent biologic potential. Two types of tumors have been described under this category: mucoepidermoid carcinoma (MEC) and sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE). The MEC shows both squamous and glandular differentiation in a background of a noninflamed gland, whereas SMECE is characterized by extensive sclerosis, squamous and glandular differentiation, a concomitant inflammatory infiltrate rich in eosinophils, and a background of lymphocytic thyroiditis. We present nine cases of these entities: five MEC and four SMECE. All tumors occurred in women (age 27 to 73 years). Five tumors showed extrathyroidal invasion and multiple lymph node metastases. One case of MEC showed a concomitant tall cell variant of papillary carcinoma with vascular invasion, and two cases showed intimately associated areas of usual papillary carcinoma. One of the latter cases also showed areas of transformation to anaplastic carcinoma. In all cases of SMECE and in only one case of MEC, the uninvolved thyroid tissue showed lymphocytic thyroiditis. Follow-up information was available in four of the nine cases (3 months to 7 years). Two patients with SMECE are alive with no evidence of disease. One patient with MEC and tall cell variant of papillary carcinoma died of disease after 3 months, and the patient with anaplastic carcinoma died after 5 months with lung metastasis. Both MEC and SMECE were positive for cytokeratin and negative for calcitonin. All cases of MEC were positive for thyroglobulin, whereas all cases of SMECE were negative. The immunohistochemical findings suggest that both MEC and SMECE have different histogenesis.

Adult↗
PubMed2000

Encapsulated follicular variant of papillary thyroid carcinoma with bone metastases.

Although true follicular thyroid carcinoma is known to metastasize via the bloodstream and give rise to bone and lung metastases, such a pattern of spread is rare in papillary thyroid carcinoma. The follicular variant of papillary thyroid carcinoma (FVPTC) is believed to behave in a clinical manner similar to usual or classical papillary cancer and to follow a similar indolent course. There have been a few reports of "aggressive" FVPTC wherein follicular patterned tumors with nuclear features of papillary carcinoma have metastasized hematogenously; these neoplasms have been diffusely invasive or multicentric in the thyroid. We report five cases of FVPTC, which were encapsulated and simulated grossly and microscopically follicular adenomas. In two of these, the primary was discovered after clinical presentation of bone metastases. In three others, bony metastases (without other nonosseous metastases) arose 7 to 17 years after thyroid lobectomy for lesions initially diagnosed as follicular adenoma In retrospect, these three encapsulated lesions had vascular invasion. We wish to bring attention to these innocuous-appearing lesions, which, although sharing nuclear features of papillary cancer, behave clinically in an unexpectedly malignant fashion.

Adult↗
PubMed2000

Tall cell papillary carcinoma of the thyroid: metastatic to the pancreas.

We present the case of a 53-year-old man with tall cell variant of papillary thyroid carcinoma that metastasized to the pancreas. The pancreas is a unique site of metastasis for differentiated thyroid cancer. The lesion in the neck and lung concentrated radioiodine, whereas the intrapancreatic lesions did not. Discordance between radioiodine studies and serum thyroglobulin in follow-up of patients with differentiated tall cell is reviewed and discussed.

Carcinoma, Papillary↗
PubMed2000

Worrisome histologic alterations following fine-needle aspiration of benign parotid lesions.

OBJECTIVE: To describe the histologic changes associated with preoperative fine-needle aspiration biopsies of benign parotid lesions and the features that distinguish these changes from malignant neoplasms. MATERIALS AND METHODS: Ten benign parotid lesions with a recent history of preoperative fine-needle aspiration were selected, including pleomorphic adenoma (4 cases), oncocytic adenoma (3 cases), myoepithelioma (1 case), Warthin tumor (1 case), and lymphoepithelial cyst (1 case). RESULTS: A spectrum of histologic alterations were observed. Alterations included squamous cell metaplasia (8 cases), infarction and necrosis (4 cases), subepithelial stromal hyalinization (3 cases), acute and chronic hemorrhage and inflammation with multinucleated giant cells (all cases), granulation tissue with subsequent fibrosis (all cases), cholesterol cleft formation (1 case), pseudoxanthomatous reaction (1 case), pseudocapsular invasion (1 case), and microcystic degeneration (2 cases). In cases with exuberant squamous metaplasia, necrosis, or subepithelial stromal hyalinization, a diagnosis of squamous cell carcinoma or low-grade mucoepidermoid carcinoma was seriously considered. CONCLUSIONS: Knowledge of a previous fine-needle aspiration procedure and awareness of its effects on histology of the subsequent parotidectomy specimens are necessary to avoid potential misdiagnosis.

Adolescent↗
PubMed2000

Thyroid sclerosing mucoepidermoid carcinoma with eosinophilia: mimic of Hodgkin disease in nodal metastases.

We present the clinical and pathologic findings of a case of sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid in a 39-year-old woman. This particular case is notable because it initially presented as a cervical lymph node metastasis, and the initial clinical and histologic impression was Hodgkin disease, nodular sclerosis type. Sclerosing mucoepidermoid carcinoma with eosinophilia is a differentiated malignant neoplasm of the thyroid that can be confused with anaplastic carcinoma, medullary carcinoma, squamous cell carcinoma, or, as in this case, Hodgkin disease. A correct diagnosis of sclerosing mucoepidermoid carcinoma with eosinophilia involves awareness of this entity and appropriate immunohistochemical analysis. In this article, we briefly review the literature and stress the histologic and cytologic findings characteristic of sclerosing mucoepidermoid with eosinophilia of the thyroid.

Adult↗
PubMed2000

Warthin-like papillary carcinoma of the thyroid.

BACKGROUND: Warthin-like papillary carcinoma of thyroid is characterized by distinct papillary formations lined by tumor cells with oncocytic cytoplasm, nuclear features of papillary carcinoma, and brisk lymphoplasmacytic infiltrates in the papillary stalks. This tumor derives its name from its close resemblance to Warthin tumor of major salivary glands. DESIGN: The clinicopathologic features of 17 patients with Warthin-like papillary carcinoma were studied. RESULTS: Fifteen tumors occurred in women and 2 arose in men (age range, 23-63 years). The lesions ranged in size from 3 mm to 2.5 cm. Fine-needle aspiration biopsies were performed in 7 cases; 4 were diagnosed as papillary carcinoma, 2 as consistent with lymphocytic thyroiditis, and 1 as atypical cells. All 17 tumors were confined to the thyroid; 6 showed prominent cyst formation and the remaining tumors were solid. In each case, the tumor arose in a background of lymphocytic thyroiditis. Nodal metastases were identified in 3 cases; however, none showed distant metastases. In 7 cases, foci of papillary microcarcinoma and follicular variant of papillary carcinoma were found in other areas of the thyroid. CONCLUSIONS: Warthin-like tumors can be mistaken for benign lymphoepithelial lesions of the thyroid, Hürthle cell carcinoma, and tall cell variant of papillary carcinoma in both fine-needle aspiration and histology specimens. Follow-up information on the previously reported cases has suggested that these tumors behave similarly to usual papillary carcinoma. The extensive lymphocytic infiltration in these tumors and their association with chronic lymphocytic thyroiditis may suggest a role for immunological mechanisms in the pathogenesis of thyroid tumors.

Adenolymphoma↗
PubMed1999

Occurrence of intercellular spaces (windows) in metastatic adenocarcinoma in serous fluids: a cytomorphologic, histochemical, and ultrastructural study.

The application of cytomorphologic criteria to the examination of serous effusions allows the reliable diagnosis of malignancy in the majority of cases. One feature observed in tissue fragments previously thought to be indicative of mesothelial origin is the presence of intercellular windows, presumably due to long surface microvilli. In this study, however, we examined cytologic preparations of 143 effusion and body-cavity washing specimens and noted distinct intercellular window formation within tissue fragments of adenocarcinoma in 13% of the cases studied. Stains for mucicarmine, Alcian blue with hyaluronidase pretreatment, and periodic acid-Schiff following diastase digestion on corresponding cell block material demonstrated that intercellular mucin contributes to such window formation in greater than half of these cases. Thus the presence of intercellular windows within tissue fragments does not, in isolation, preclude the diagnosis of malignancy in serous effusions.

Adult↗
PubMed1999

Papillary formations in metastatic melanoma.

Cytomorphologic features of melanoma can be extremely variable, in that they can mimic other poorly differentiated neoplasms. Ten cases of metastatic melanoma with distinct, cohesive, papillary tissue fragments observed in fine-needle aspiration (FNA) specimens are reported. These papillary fragments exhibited a central fibrovascular core with attached tumor cells, in a background of single scattered malignant cells, macrophages, and focal necrosis. The aspiration sites included regional or distant palpable lymph nodes, pancreas, bone, and skin. Nine cases had a histologic diagnosis of primary cutaneous melanoma, and in one case the primary skin tumor was detected after the diagnosis was established by FNA of the metastasis. Immunohistochemical studies (S-100 protein, HMB-45 antigen, and factor VIII) were performed in four cases, and electron microscopy in one, confirming the diagnosis of melanoma. An awareness of this cytomorphologic variation of papillary formations in cytology preparations from metastatic melanoma is important and can prevent potential inaccurate interpretation.

Adult↗
PubMed1999

Cytomorphology of metastatic mesothelioma in fine-needle aspiration specimens.

The morphologic features of mesothelioma occurring in serous fluids, as well as fine-needle aspiration (FNA) of primary tumors, have been extensively described. Descriptions of the FNA findings in metastatic lesions of mesothelioma, however, are limited to single cases. In this report, we illustrate the cytomorphologic features of four cases of metastatic mesothelioma which underwent FNA, and one additional cytologic preparation taken from a surgically-excised metastatic lesion. The cytomorphologic features of metastatic mesothelioma varied greatly among individual cases with respect to the degree of nuclear pleomorphism, amount of cytoplasm, and degree of cellular cohesion. However, one feature which was consistently seen was the presence of numerous distinct, uniformly small intracytoplasmic vacuoles, believed to represent intracellular fat and glycogen. These morphologic features are illustrated, and the differential diagnosis of intracytoplasmic vacuoles within epithelioid tumor cells in primary and metastatic lesions is discussed.

Aged↗
PubMed1999

Millipore filter cell block preparation: an alternative to cell block in nongynecologic specimens of limited cellularity.

The use of membrane filters to concentrate cytology specimens was first described by Seal (Cancer 1956; 9:866-868). We report on a technique in which a portion of Papanicolaou-stained Millipore filter (Millipore Corp, Bedford, MA) preparation can be converted into a paraffin block for hematoxylin-eosin (H&E) preparations and immunocytochemical analysis (ICC). Seven cases with moderate cellularity and no cell block preparation were retrieved from our cytopathology files. The specimens included: 4 pleural effusions with metastatic adenocarcinoma, and 3 FNA specimens (1 metastatic melanoma, 1 metastatic adenocarcinoma, and 1 thyroid/papillary carcinoma). The filter was removed from the slide, cut in half, and subjected to paraffin embedding in the usual fashion (postfixed in 10% neutral-buffered formalin). Four-micron-thick sections were cut onto Probe-On (Fisher Scientific, Pittsburgh, Pa) slides. ICC was performed using the avidin-biotin-peroxidase complex technique and capillary gap technology. Antibodies included CAM5.2, AE1/AE3, CEA, CD15, LCA, PanCK, S100, HMB45, and thyroglobulin. All cases showed excellent preservation of cellular morphology on H&E. ICC performed on Millipore filter cell block preparations showed specific antibody staining patterns with preservation of cellular details. All antibodies showed their specific staining patterns with clean background and lack of nonspecific staining. This technique has the following advantages: 1) offers an alternative to cell blocks in moderately cellular specimens; 2) clean background; 3) preservation of cytology specimens for future studies.

Adenocarcinoma↗
PubMed1999

Differential expression of cytokeratins in follicular variant of papillary carcinoma: an immunohistochemical study and its diagnostic utility.

The follicular variant of papillary carcinoma (FVPTC) is characterized by follicular growth pattern and tumor cells with appropriate nuclear features of papillary carcinoma. However, occasionally these lesions may show focal or multifocal instead of diffuse distribution of nuclear features of papillary carcinoma. Such lesions can be underdiagnosed as benign follicular nodule. Previous studies have shown that cytokeratins, especially 19, are helpful in differentiating papillary carcinoma from other benign and malignant follicular patterned lesions. In this study, we applied monoclonal antibodies to CK5/6/18, CK18, CK10/13, CK20, CK17, and CK19 to paraffin sections of formaldehyde-fixed tissue from 26 cases of FVPTC with multifocal distribution of papillary cancer nuclei, 10 cases of usual variant of papillary carcinoma, 1 case of Warthin's tumor-like papillary carcinoma, and 2 cases of the columnar cell carcinoma. CK19 stained strongly and diffusely all cases of papillary carcinoma. FVPTC cases showed strong staining of the areas with papillary cancer nuclei in all cases and moderate to strong staining in areas of tumor without obvious nuclear features of papillary cancer. Normal thyroid parenchyma adjacent to the tumor nodule showed focal staining in most cases; however, tissue away from the tumor nodule failed to show any staining. All cases of usual type of papillary carcinoma, 2 of columnar cell carcinoma, and 1 Warthin's tumor-like papillary carcinoma showed strong and diffuse staining with CK19 and failed to show any staining of adjacent normal thyroid parenchyma. Similar but less intense staining patterns were seen with CK17 and CK20. The control group, consisting of cases of follicular adenoma, follicular carcinoma, and hyperplastic nodule, showed no staining with CK19. We suggest that if one is using immunohistochemistry to aid in the diagnosis of cases of FVPTC with multifocal distribution of nuclear features of papillary cancer, an antibody panel comprising CKs 17, 19, and 20 may prove helpful. In addition, we hypothesize that the staining of adjacent nontumorous thyroid parenchyma with CK19, seen only in cases of FVPTC, suggests that some factors secreted/produced by this particular tumor may lead to modification in keratin expression of surrounding follicular epithelium.

Biomarkers, Tumor↗
PubMed1999

Post-fine-needle aspiration spindle cell nodules of the thyroid (PSCNT).

Postoperative spindle cell proliferations have been well described in the lower genitourinary tract. These lesions show an exuberant proliferation of spindle cells with bland cytology and numerous mitoses. We report similar lesions in the thyroid gland of 10 patients who had undergone fine-needle aspiration (FNA). The proliferations were nodular, measured 1 to 7 mm, and were relatively circumscribed and nonencapsulated. In most cases, they were limited to the central part of the preexisting thyroid lesions and showed plump spindle cells with a rich network of thin-walled blood vessels and an inflammatory component constituted mainly of histiocytes and few lymphocytes. Mitotic figures were exceedingly rare. Immunostains showed diffuse positivity with smooth muscle actin, suggesting a myofibroblastic nature to the spindle cell component, and endothelial markers highlighted a network of thin-walled blood vessels. The histiocytic component stained with the macrophage marker CD68. The degree of cellularity was variable and may be related to the interval between FNA and surgery, size of the biopsy needle, and undetermined host response factors. We believe it is important to recognize these nodules as posttraumatic benign lesions without clinical consequence to avoid misdiagnosis of other lesions in thyroid-containing spindle cells, such as anaplastic carcinoma, medullary carcinoma, and sarcoma.

Adult↗
PubMed1999

Follicular variant of papillary carcinoma. Cytologic and histologic correlation.

The cytologic diagnosis of follicular variant of papillary thyroid carcinoma (FVPTC) can be difficult owing to the paucity of nuclear changes of papillary carcinoma and overlapping features with other follicular-derived lesions. We report our fine-needle aspiration (FNA) experience with 17 histologically proved cases of FVPTC with a preceding FNA. All cases showed increased cellularity and a background of moderate to abundant thin watery colloid with variable amounts of thick eosinophilic colloid. The cells were arranged mainly in monolayer sheets and syncytial fragments; occasional microfollicle formation with abundant fine eosinophilic cytoplasm was seen. Nuclear enlargement was a consistent finding in all cases. Only 5 cases showed prominent nuclear features of papillary carcinoma. Histologic examination showed encapsulated follicular-patterned nodules with multifocal random distribution of nuclear features of papillary carcinoma that were more pronounced in the subcapsular locations of the lesions. This morphologic heterogeneity explains the variability seen in FNA specimens of FVPTC and may result in false-negative diagnoses. We believe that these findings should be considered when interpreting follicular lesions; suspicion of an FVPTC should be conveyed in the cytopathology report, which may prompt intraoperative assessment to avoid a second surgical intervention for completion thyroidectomy.

Adult↗
PubMed1999

Tumor-to-tumor metastasis to follicular variant of papillary carcinoma of thyroid.

OBJECTIVE: To describe and document tumor-to-tumor metastases in the thyroid gland. METHODS AND RESULTS: In this series we describe 3 cases of tumor-to-tumor metastasis in which the recipient tumor was a follicular variant of papillary thyroid carcinoma. The donor tumors and sites were small cell carcinoma of the lung, neuroendocrine carcinoma probably of pancreatic origin with initial presentation as liver metastasis, and clear cell carcinoma of the kidney with metastasis to liver and pancreas. The donor tumor cells infiltrated the substance of the follicular variant of papillary thyroid carcinoma, the nontumorous thyroid parenchyma, and the lymphovascular spaces. Small cell carcinoma and neuroendocrine carcinoma showed positive reactivity for neuroendocrine markers and were negative for thyroglobulin and calcitonin. The follicular variant of papillary thyroid carcinoma showed positivity with thyroglobulin and cytokeratin 19. CONCLUSIONS: Although tumor-to-tumor metastases in thyroid gland are exceedingly rare, one should be aware of this phenomenon as the metastatic lesion may simulate a thyroid primary. History of a previous tumor and immunohistochemical stains can be helpful in distinguishing between primary and metastatic thyroid neoplasms.

Adenocarcinoma, Clear Cell↗