Thyroid spindle-cell tumor with mucous cysts. An intrathyroid thymoma?

An apparently new tumor entity of the thyroid is reported. The tumor was histologically characterized by good demarcation, lobular pattern, keratin-positive spindle cells, glandular elements, stromal hyalinization, and calcifications. These findings are suggestive of a tumor related to spindle-cell thymoma and apparently closely related to the recently described entity, ectopic hamartomatous thymoma. The patient, a 23-year-old man is alive and well 10 years after diagnosis. Two histologically similar cases have earlier been reported in the English literature under the heading "malignant teratoma."

Medullary carcinoma of the thyroid with carcinoid-like features.

AIMS: To show that medullary carcinomas of the thyroid are morphologically indistinguishable from gut carcinoids: the value of histochemistry in their identification and differential diagnosis from metastatic carcinoid tumours to the thyroid and some follicular cell neoplasms. METHODS: 15 thyroid medullary carcinomas with features of gut carcinoids were histochemically studied for the presence of argyrophil and argentaffin granules, and calcitonin, thyroglobulin, and serotonin immunoreaction. RESULTS: Histological features of midgut (classic) carcinoids were observed in two tumours, foregut carcinoids in 12, and hindgut carcinoids in one. All tumours showed, to a greater or lesser extent, a calcitonin immunoreaction and argyrophilia. These markers were present only in a small area showing a classic pattern of thyroid medullary carcinoma in the hindgut carcinoid-like neoplasm. Argentaffin granules and serotonin immunostaining occurred in occasional cells from four foregut carcinoid-like tumours. Thyroglobulin was not expressed in all cases and amyloid stroma was expressed in three. CONCLUSIONS: In some cases a diagnosis of metastatic carcinoid tumour to the thyroid can be considered only after ruling out clinically and histochemically medullary carcinoma of the thyroid. Immunolocalisation techniques are also essential for the differentiation between medullary carcinoma and thyroid follicular cell neoplasms that resemble carcinoid tumours. It is proposed that this tumour variant to be incorporated into current classifications as another histological subtype of C cell carcinoma.

Factor VIII as a marker of endothelial cells in follicular carcinoma of the thyroid.

Factor VIII-related antigen is a recognised marker of endothelial cells. A brief immunocytochemical study of its distribution in follicular carcinoma of the thyroid and its value in the recognition of vascular invasion by this tumour has been carried out. Ten cases of follicular carcinoma of the thyroid were studied. In each strong endothelial staining was found in the majority of vessels in the adjacent normal thyroid. Lymphatic endothelium was negative. In eight of the 10 cases the staining of vessels within the tumour was absent or very weak. Staining was also absent in the majority of vessels completely occluded by tumour, but was present in the endothelium of vessels only partly occluded by tumour. It is concluded that factor VIII-related antigen staining has only limited value in the recognition of vascular invasion in follicular carcinoma. The absence of vascular staining in the tumour leads us to suggest that inhibition of factor VIII production by the tumour could be a possible mechanism which facilitates vascular invasion and metastasis.

Adrenocortical oncocytoma.

The histopathology and ultrastructural features of an adrenocortical oncocytoma are reported. The tumour was discovered incidentally during investigation for hypertension in a 72 year old female. Oncocytic tumours of the adrenal cortex are rare, with only 20 examples described in English language reports. Most have been non-functioning and benign, like the present example. Molecular studies may help assess the significance of oncocytic change in the pathogenesis and behaviour of oncocytic neoplasms.

Cytological features of non-small cell carcinomas of the lung in fine needle aspirates.

Fifty eight lung tumours were typed according to the second World Health Organization histological classification and compared with the cytological appearances obtained by fine needle aspiration in a total of 47 primary non-small cell carcinomas. The presence of glands, cell balls, branching or papillary structures, cylindrical cells and nuclear grooving were major diagnostic indicators for adenocarcinoma. Cytoplasmic macrovacuoles were more common in adenocarcinomas (69%) than in squamous (37%) and large cell (50%) carcinomas. Two or more of these features were combined in all well and moderately differentiated adenocarcinomas and in 67% of poorly differentiated adenocarcinoma. The major cytological indicators for squamous carcinomas were the presence of keratin and eosinophilic spindle cells with glassy or laminated cytoplasm. Granular cytoplasm was not specific for any histological type. A combination of the major features for both adeno- and squamous carcinoma was present in 58% of adeno-squamous carcinomas, including some poorly differentiated types. Correct typing could be obtained in almost all the well and moderately differentiated carcinomas and in about two thirds of the poorly differentiated tumours using FNA, provided that combinations and not individual variables are considered.

Occult papillary microcarcinoma of the thyroid--a potential pitfall of fine needle aspiration cytology?

The use of fine needle aspiration cytology detected papillary carcinoma in two patients with multinodular goitre measuring 0.7 cm and 0.9 cm in diameter, respectively. Like most of the cases from previous large series, the tumours progressed slowly as shown by absence of enlarged glands on surgical exploration and no clinical signs of metastasis after two and five years of follow up. This study shows that aspiration cytology can detect a virtually harmless occult papillary carcinoma that will oblige patients to have surgery. This very occasional "pitfall" of fine needle aspiration should not preclude this well known beneficial method from being used in the management of thyroid disease.

Parenchymatous thyroid nodules: a histocytological study of 31 cases from a goitrous area.

AIMS: To analyse the benefits and limitations of fine needle aspiration in the cytological differentiation of parenchymatous nodular goitres from follicular tumours in an endemic area. METHODS: Cytological smears of fine needle aspirates from 31 parenchymatous nodular goitres were studied. A sample from the punctured nodules was fixed in formalin and stained with haematoxylin and eosin for histological analysis. RESULTS: All nodules occurred in a multinodular gland, were well circumscribed, did not compress surrounding thyroid tissue, and for the most part, were unencapsulated. Two cases showed cytological features of nodular goitre, two of colloid cysts; the remaining 27 were cytologically indistinguishable from follicular lesions. CONCLUSIONS: Most of the parenchymatous nodules studied had features suggestive of follicular lesions or neoplasia, but surgical treatment should only be considered after hormone treatment has proved unsuccessful, and when they are not suspected as malignant clinically. Fine needle aspiration is useful as a diagnostic and screening aid, but the results should be interpreted with caution to prevent unnecessary surgery.

Chromogranin A immunoreactivity compared with argyrophilia, calcitonin immunoreactivity, and amyloid as tumour markers in the histopathological diagnosis of medullary (C-cell) thyroid carcinoma.

Applying the WHO criteria for the histopathological diagnosis of medullary thyroid carcinoma (MTC)--as well as the criterion that a significant amount of argyrophil cells, amyloid deposits, or calcitonin (CT) immunoreactive cells shall be present--122 cases were identified from the files of the Swedish Cancer Registry. Both non-occult (n = 110) and "occult" (less than 1 cm in diameter) (n = 12) MTCs were included. Both primary tumours (n = 91) and metastatic lesions (n = 31) were investigated. The specimens available were all only conventionally formalin-fixed and paraffin-embedded. The presence of neoplastic cells immunoreactive with antisera against chromogranin A (Chr A) was compared with that of the other three MTC markers. Chr A immunoreactive cells were present in practically all the cases. Similar results were obtained when the argyrophil reaction alone and CT immunoreactivity alone were used as markers. When two of the three MTC markers were combined, it was found that virtually everyone of the 122 tumours could be identified as a MTC. In contrast, the presence of amyloid deposits was found to be a less constant MTC marker; whereas 94% of the primary tumours had amyloid deposits, they were present in only approximately 70% and 60% of the metastatic and "occult" tumours respectively. No differences in the staining reaction patterns were found between familial (n = 18) and the sporadic (n = 104) types of MTC.(ABSTRACT TRUNCATED AT 250 WORDS)

Nodular goiter: a histo-cytological study with some emphasis on pitfalls of fine-needle aspiration cytology.

A comprehensive comparative histo-cytological study of 48 nodular goiters from an endemic goiter region was undertaken. Practically all features observed on the biopsies were identified, although with less frequency, on the smears. In agreement with previous observations, characteristic components of nodular goiter (NG) in aspirates included small to medium size epithelial cells with regular round nuclei, honeycomb pattern, large follicles, papillae showing the previously mentioned epithelial features, oxyphilic cells, and moderate to abundant background colloid material and thyroid phagocytes (macrophages). All eight features occurred together in only 2% of the studied cases, seven in 6 (12.5%), six in 4 (8%), five in 6 (12.5%), four in 12 (25%), three in 6 (12.5%), two in 11 (23%), and one in 2 (4%) cases, respectively. Regardless of the number and combination of features present, specific identification of NG on the smears may not always be possible and diagnostic pitfalls include thyroid cyst, Hashimoto's thyroiditis, granulomatous lesions, and, more frequently, follicular neoplasia. Our findings suggest that thyroid aspirates should be analysed with critical clinico-pathological approach and surgery considered only for nodules that are clinically suspicious or unresponsive to hormonotherapy when a diagnosis of follicular neoplasia is made.

Usefulness of fine needle aspiration of the thyroid in an endemic goiter region.

The accuracy of fine needle aspiration (FNA) cytology of the thyroid was addressed in 142 nodular goiters from an endemic goiter region. The aspirations and their interpretation were based on the methodology of the Karolinska Hospital. For practical purposes, the follicular lesions were divided into type I (benign), type II (atypical benign) and type III (suspicious). Excluding the follicular lesions, the cytohistologic agreement for the whole series was 87%, with a correlation of 81.5% for carcinomas. The type I and type II follicular lesions were benign on histologic grounds; 39% of the carcinomas were detected in the type III follicular lesions. The 0.7% false-positive diagnoses increased to 15% when type III follicular lesions were included. No false negatives were recorded. These observations, together with the increase of surgically resected thyroid carcinomas after FNA was accepted as a diagnostic modality, indicate that FNA biopsy of the thyroid is an accurate diagnostic method and is useful in selecting patients for subsequent surgery in areas of endemic goiter.

Cytopathology of the tall cell variant of thyroid papillary carcinoma.

The tall cell variant of thyroid papillary carcinoma differs from classic papillary carcinoma in its more aggressive clinical behavior, cell type (columnar amphophilic to oxyphilic) and higher frequency of stromal lymphoid infiltrate. A retrospective study of three such cases was made, with an emphasis given to the utility of fine needle aspiration cytology in their identification. Aspirates revealed papillary fronds and cyanophilic and oxyphilic neoplastic cells with a high proportion of nuclear grooves and cytoplasmic inclusions. These nuclear details allowed a specific diagnosis of papillary carcinoma with oxyphil cells as compared to oxyphilic cell follicular tumors. Smears from two cases showed, in addition, lymphoid cells and multinucleate giant cells. In them a diagnosis of coexisting Hashimoto's disease, granulomatous thyroiditis or inflammatory tumor stroma could not be excluded cytologically.

Cytologic findings in the follicular variant of papillary carcinoma of the thyroid.

Fine needle aspirates from 8 thyroid papillary carcinomas, follicular variant, were studied. Histologically the tumors were composed exclusively of follicles (four cases) or an admixture of follicular and trabecular structures (four cases). Follicles were identified in smears from seven cases (87.5%) and sheets reminiscent of a trabecular pattern in one (12.5%). Colloid material presented as intraluminal (one case) or extraluminal, dense, round masses (six cases). Nuclear cytoplasmic inclusions occurred in seven (87.5%) of the cases. All these features have been described for follicular lesions or neoplasia together with occasional nuclear grooves, as occurred in two (25%) of the studied cases. In the other six (75%) cases, a moderate to high proportion of neoplastic cells with nuclear grooves facilitated the diagnosis of papillary carcinoma. Our findings suggest that a careful microscopic search for nuclear grooves should be attempted in aspirates yielding a diagnosis of follicular neoplasia that could otherwise be indistinguishable from the follicular variant of papillary carcinoma of the thyroid.

[Association between a meningioma and an occult thyroid carcinoma in congenital hypothyroidism]. / Asociación entre meningioma y carcinoma oculto de tiroides en un hipotiroidismo congénito.

The presence of a thyroid carcinoma and a defect in thyroid hormone synthesis in a 27 year ols female is reported. When she was 13 years old a clinical diagnosis of hypothyroid cretinism was made, based on a defect of iodide organification which was demostrated by thiocyanate test showing a discharge of 55 % of 131I at 45 minutes. She intermittently received thyroid hormone until she died. Few days before dying she had normal values of T3, T4 and TSH. Her parents are related and she had a 35 years old sister with a similar type of thyroid hormone synthesis defect. She died with bilateral broncopneumonia following a 3rd grade coma due to a meningioma that compressed the encephalus. The thyroid weighed 12 gms and had a 0.8 x 0.6 x 0.3 cm occult thyroid carcinoma, follicular type, with areas of undifferentiated pattern. As far as we know there are no reports in the literature on the coexistence between an occult thyroid carcinoma and a congetal hypothyroidism without goiter. It may be postulated that the administration of thyroid hormone, inhibiting the release of TSH, may have avoided neoplastic growth despite the low grade of differentation in some areas. The rest of the gland was hypotrophic because of lack of hypophyseal stimulus. This rare coexistence between thyroid carcinoma and meningioma as an autosomal recessive congenital disorder is discussed.

Undifferentiated (anaplastic) thyroid carcinoma and iodine intake in Salta, Argentina.

This study was conducted to investigate the natural history of undifferentiated thyroid carcinoma (UTC) in the iodine-deficient province of Salta, Argentina, in relation to salt iodization and health care standards. Five hundred ninety-three thyroid cancers diagnosed from 1958 to2012 were reviewed based mainly on the WHO classification and grouped into three periods, one before and two after iodine prophylaxis. The incidence of UTC was analyzed in relation to changing concentrations of potassium iodide (KI) in salt during the prophylaxis period (from 40 to 33.3 mg KI/kg salt), establishment of primary health care centers throughout the region, and use of fine needle aspiration (FNA) cytology. Twenty-nine UTCs were found in the whole series. The frequency of UTC decreased from 15.2 % (9/59 cases) in the first period to 2.6 % (10/381 cases) well after salt iodination (x (2) Fisher's test, p < 0.0002), and the incidence from 1.4/10(6)/year to 0.1/10(6)/year (Student's t test, p < 0.06), respectively. The decline of UTC after iodine prophylaxis occurred even after decreasing concentrations of KI in salt and timely coincided with the establishment of primary health care centers throughout the region and routine use of FNA. The lower rate of UTC after iodine prophylaxis in the province of Salta is mostly related to earlier detection of more differentiated thyroid tumors rather than higher salt iodization.