Oxyphil cells in thyroid disease: a uniform change?

Adrenocortical oncocytoma presenting as Cushing's syndrome: an additional report of a paediatric case

Oncocytomas are tumours predominantly or exclusively composed of oncocytes, cells with granular and eosinophilic cytoplasm filled with mitochondria. Although they can occur in every organ, they are rare in adrenal glands, and in paediatric patients they are even rarer, with only three case reports previously published. We present a preschool child developing Cushing's syndrome due to an adrenocortical oncocytoma, which was confirmed immunohistochemically with antibodies to the mitochondrial electron complex 2. A 5.8-year-old girl presented with clinical features of Cushing's syndrome. ACTH-independent hypercortisolism was confirmed biochemically and a left adrenal mass was detected by imaging and removed by laparotomy. Histopathological analysis revealed a tumour composed of more than 95 % of oncocytes, confirmed immunohistochemically with antibodies to subunits A and B of the mitochondrial enzyme succinate dehydrogenase. Using the Lin-Weiss-Bisceglia score system and the reticulin algorithm, this tumour was categorized as a benign adrenocortical oncocytoma. The patient currently has 64 months of follow-up, without any evidence of relapse of symptoms. To our knowledge, we herein present the youngest patient developing an adrenocortical oncocytoma and the first manifestation of Cushing's syndrome due to this rare neoplasm in paediatric patients. We also emphasize the clinical usefulness of immunohistochemistry to the mitochondrial enzyme succinate dehydrogenase to confirm the oxyphilic nature of adrenocortical oncocytomas.

The Thyroid Hürthle (Oncocytic) Cell and Its Associated Pathologic Conditions: A Surgical Pathology and Cytopathology Review

Context.—Hürthle cells are eosinophilic, follicular-derived cells that are associated with a variety of nonneoplastic and neoplastic thyroid lesions. The differential diagnosis of Hürthle cell lesions is quite broad.

Objective.—To review the pathologic conditions associated with Hürthle cells in the thyroid and to discuss pathology of thyroid lesions associated with oncocytic cytology.

Data Sources.—A variety of thyroid nonneoplastic (autoimmune thyroiditis, multinodular goiter) and neoplastic conditions (Hürthle cell adenoma, Hürthle cell carcinoma) are associated with Hürthle cell cytology. In addition, there are several thyroid neoplasms that should be considered when one observes a Hürthle cell neoplasm in the thyroid (oncocytic variant of medullary carcinoma, several variants of papillary thyroid carcinoma).

Conclusions.—Oncocytic cytology is seen in a variety of thyroid conditions that are associated with a broad differential diagnosis and care must be used for accurate diagnosis. Newer molecular-based techniques may be useful for further classification of thyroid neoplasms with oncocytic pathology.

Diagnostic utility of intracytoplasmic lumen and transgressing vessels in evaluation of Hürthle cell lesions by fine-needle aspiration

INTRODUCTION

Recent abstracts have emphasized the importance of recognizing intracytoplasmic lumen and transgressing vessels as useful criteria enabling distinction between Hürthle cells encountered in neoplastic and nonneoplastic thyroid aspirates. The purpose of this retrospective study was to evaluate if application of these criteria improves specificity and sensitivity of cytologic diagnosis of true Hürthle cell neoplasms.

MATERIALS AND METHODS

We retrospectively reviewed 30 fine-needle aspirates of thyroid with cytologic diagnosis of Hürthle cell neoplasms (13 cases) and nonneoplastic thyroid with prominent Hürthle cells (17 cases). All cases were evaluated for the presence of intracytoplasmic lumen and transgressing vessels and were reclassified as neoplastic or nonneoplastic based on the presence or absence of 1 or both of these criteria. Surgical follow-up was available in all cases.

RESULTS

Surgical follow-up in 13 cases of Hürthle cell neoplasms revealed Hürthle cell carcinoma (3 cases), Hürthle cell adenoma (6 cases), and Hashimoto's thyroiditis (4 cases). Seventeen cases with nonneoplastic diagnosis revealed Hürthle cell carcinoma (1 case), Hashimoto's thyroiditis (12 cases), and nodular goiter (4 cases). After application of the previously mentioned cytologic criteria, the cytologic diagnoses were reclassified as Hürthle cell neoplasms (13 cases) and nonneoplastic thyroid (17 cases). The true sensitivity of the test before and after the application of the criteria was 90% and 100%, respectively. The true specificity before and after the application of the cytologic criteria was 65% and 85%, respectively.

CONCLUSIONS

Intracytoplasmic lumen and transgressing vessels are helpful features in distinguishing neoplastic and nonneoplastic Hürthle cell thyroid lesions. Use of these criteria may improve the specificity and sensitivity of the cytologic diagnosis.

Usefulness of computer-aided karyometric examination in preoperative differentiation of Hürthle cell lesions

We have previously reported that there is a significant difference in the mean size of thyrocyte nuclei among patients with nodular goiter, follicular adenoma, and follicular carcinoma. In the present study, we have examined karyometric parameters of Hürthle cells in smears collected from 41 patients with Hürthle cells adenomas, Hürthle cells carcinomas, nodular goiter, and lymphocytic thyroiditis. The karyometric evaluation was performed with the image analysis computer system-Karyometry Manager 1.2. We measured the mean volume, the mean intersection area, and the mean perimeter of 100 nuclei in each routine smear. We found that the sizes of Hürthle cell nuclei could be arranged in the ascending order from the nodular goiter, through lymphocytic thyroiditis to Hürthle cell neoplasms, but those differences did not reach a border of statistical significance.

Mesectodermal leiomyoma of the ciliary body: case report

The clinical, light microscopical, and electron microscopical features of a mesectodermal leiomyoma of the ciliary body are presented. This exceptionally rare and apparently benign tumour is considered to be of neural crest origin. In the case described the tumour cells were seen to contain thin filaments with focal densities and conspicuous numbers of mitochondria, and smooth muscle protein was demonstrated by immunohistochemical means.