Fine-needle aspiration diagnosis of carotid body tumor: report of a case and review of experience with cytologic features in four cases

Follicular Neoplasm of Thyroid Revisited: Current Differential Diagnosis and the Impact of Molecular Testing

The diagnosis of "follicular neoplasm" (FN) in thyroid cytopathology has a long history that originated not long after the practice of fine-needle aspiration (FNA) of thyroid nodules. From the outset, this interpretive category was intended to convey a set of differential diagnoses rather than a precise diagnosis, as key diagnostic features, such as capsular and vascular invasion, were not detectable on cytology preparations. Cytologic-histologic correlation studies over the past several decades have shown that FN interpretation can be applied to the spectrum of nonneoplastic tumors to carcinomas. Most tumors classified as FN include follicular adenoma, follicular carcinoma, noninvasive follicular thyroid tumor with papillary-like nuclear features, and follicular variant of papillary thyroid carcinoma. Less common entities that may be classified as FN on FNA include hyalinizing trabecular tumor (HTT), poorly differentiated thyroid carcinoma, medullary carcinoma, and nonthyroidal lesions such as parathyroid tissue, paraganglioma, and metastatic tumors. Advances in our ability to detect characteristic molecular alterations (eg, GLIS gene rearrangements for hyalinizing trabecular tumor) in FNA samples may assist in the identification of some of these entities. In this review, we summarize the pathophysiology, history, and evolution of the terminology and the current differential diagnosis according to the recently published 2022 World Health Organization classification, molecular testing, and management of nodules classified as FN.

Thyroid Paraganglioma: "Naked" Nuclei as a Clue to Diagnosis on Imprint Cytology

A cytologic diagnosis of paraganglioma of the thyroid is difficult to make because the thyroid gland is an unusual location for such a tumor and the cytologic findings overlap with other benign and malignant thyroid tumors. We report the case of a 28-year-old female presenting with a solitary mass of the right thyroid gland. A diagnosis of paraganglioma was made on the resected specimen. At the time of tumor resection, imprint cytology was performed. The imprint was hypercellular with cohesive sheets of round cells showing anisokaryosis and anisocytosis. Moreover, there was a second cell type consisting of oval nuclei with dispersed nuclear chromatin present within the sheets and separate as "naked" nuclei. By immunohistochemistry, the cohesive round cells were positive for chromogranin A, indicating chief cells. The naked nuclei were positive for S-100 protein, indicating sustentacular cells. To the best our knowledge, this is the first case report describing naked nuclei as a cytologic feature of paraganglioma. Identification of sustentacular cells provides a clue for the cytologic diagnosis of paraganglioma.

Cytomorphologic spectrum in aspirates of extra-adrenal paraganglioma

Background:

Paraganglioma is a rare tumor arising from clusters of neuroendocrine cells in association with sympathetic and parasympathetic nervous system. It poses a diagnostic challenge because of its widespread anatomic distribution, subtle clinical manifestations, and a variety of morphologic patterns.

Aim:

The aim of this study is to have an insight into the diverse morphologic spectrum of extra-adrenal paraganglioma (EAP).

Materials and Methods:

A retrospective analysis of seven cytologically diagnosed cases of EAP over a period of 10 years was performed. There were five superficial swellings and two deep seated retroperitoneal masses. The superficial swellings were aspirated directly, and the retroperitoneal masses were aspirated under ultrasound guidance using 22-gauge lumbar puncture needle fitted to a 10 mL syringe. Smears were reviewed for cellularity, pattern, cell shape, cytoplasm, nuclear features, and background.

Results:

The age of patients ranged from 25 to 75 years; four patients were males and three were females. Sites involved were carotid body region (four cases), para-pharyngeal space (one case) and para-aortic region (two cases). All the cases yielded hemorrhagic material on fine-needle aspiration. Smears showed scattered and clusters of cells and loosely cohesive acini of tumor cells. Cells were round to polygonal with pleomorphic nuclei, granular chromatin, inconspicuous nucleoli, and moderate to abundant cytoplasm containing fine pink granules and vacuolations. The cases were confirmed on radiology and histopathology.

Conclusion:

The cytologic features in EAP along with pertinent clinicoradiologic findings help in making an accurate preoperative diagnosis of an otherwise rare tumor.

Paragangliomas of the carotid body: current management protocols and review of literature

Paraganglioma is a rare neoplasm arising from carotid body usually benign and constitute 0.5 % of all total body tumors. They constitute 60-70 % of head and neck paraganglioma and resemble other paragangliomas of the body like glomus jugulare, glomus tympanicum, and pheochromocytoma. This is a retrospective analysis of the medical records of carotid body paraganglioma cases. Nine patients operated during the study period and the follow up traced were included in the study. Seven females and 2 males were analysed. Six had tumor on the left side and 3 had on the right side. All the cases surgical excision was done by a tranverse incision as 2 patients had Shamblin I, 5 patients had Shamblin II, and 1 patients Shamblin IIIa. All the Shamblin I had tumor away from the carotids and were easily dissected without vessel damage, a sub adventitial tumor excision was performed in all the 5 cases of Shamblin II, 1 case of Shamblin IIIa was dissected with difficulty without sacrificing or vessel reconstruction. Paraganglioma of the carotid body should be considered as a differential diagnosis for painless lateral neck masses. Larger tumors need a multidisciplinary team of head and neck with vascular surgeons for better results.

Management of carotid body tumors

The carotid body tumor is a rare neoplasm that has generated much literature over the past century, and for which continued controversy exists regarding natural history, biologic behavior, proper technique of excision, and the risk of morbidity and mortality. This article discusses overall management of carotid body tumors.

Diagnostic challenges in the fine-needle aspiration diagnosis of carotid body paragangliomas: report of two cases

Two cases of carotid body paragangliomas sampled by fine-needle aspiration (FNA) cytology prior to other medical diagnostic studies are presented. In the first case, the presence of an ipsilateral ulcerative lesion of the nasopharynx along with pronounced atypia of the specimen posed a challenge to the correct cytologic interpretation, which was initially sidetracked in favor of a metastatic epithelial lesion. In the second case, a tumor mass of unusually large size and extension which included the pharynx, coupled with a large amount of profusely hemorrhagic aspirate, presented a diagnostic problem, which was overcome by processing part of the specimen as a cell block, which by its histologic and immunochemical features provided a definitive pathologic diagnosis. In handling these two clinically complex cases of carotid paraganglioma, two learning principles became clear on how to reach a correct FNA diagnosis in such lesions: 1) The anatomic location of the lateral neck mass with its prolonged history, along with a hemorrhagic FNA specimen exhibiting at least some cytologic features reminiscent of endocrine neoplasm, are among the factors that help in arriving at a suggestive diagnosis of paraganglioma, when other clinical features tend to sidetrack from interpretation of the cytologic changes. 2) In the practice of FNA cytology, if the possibility of paraganglioma arises, processing part of the specimen as a cell block with accompanying histology and immunohistochemistry can provide a definitive diagnosis of such lesion.

Schwannoma of the Cervical Sympathetic Chain: It's Not a Carotid Body Tumor

Schwannoma of the cervical sympathetic chain is a rare nerve tumor with fewer than 40 confirmed cases in the English literature. These lesions typically present as an asymptomatic neck mass and are easily mistaken for a carotid body tumor during the initial workup. We report a case of schwannoma of the cervical sympathetic chain in a 35-year-old man followed by a review of the current literature.