|Year : 2018 | Volume
| Issue : 5 | Page : 449-451
Undifferentiated/Anaplastic thyroid carcinoma: A cytological case report
Sunil Yogiraj Swami, Arun D Chopwad, Arvind G Valand
Department of Pathology, SRTR Government Medical College, Ambajogai, Maharashtra, India
|Date of Web Publication||5-Sep-2018|
Sunil Yogiraj Swami
Bhagwanbaba Chowk, Gitta - Road, Shepwadi, Ambajogai - 431 517, Beed, Maharashtra
Source of Support: None, Conflict of Interest: None
Undifferentiated thyroid carcinoma is a relatively uncommon highly malignant tumor originating from the follicular cells of thyroid gland having poor prognosis. It accounts for 2%–5% of all thyroid carcinomas and patients typically present with a rapidly growing anterior neck mass with aggressive symptoms. A 70-year-old female presented with diffuse neck swelling measuring 6 cm × 5 cm for 1-month duration which was associated with mild dyspnea. Fine needle aspiration cytology (FNAC) from the swelling revealed a cellular smear comprising of highly pleomorphic follicular epithelial cells arranged in clusters and singly scattered with a background of bizarre tumor giant cells and inflammatory cells.
Keywords: Anaplastic, cytology, thyroid carcinoma, undifferentiated
|How to cite this article:|
Swami SY, Chopwad AD, Valand AG. Undifferentiated/Anaplastic thyroid carcinoma: A cytological case report. Med J DY Patil Vidyapeeth 2018;11:449-51
|How to cite this URL:|
Swami SY, Chopwad AD, Valand AG. Undifferentiated/Anaplastic thyroid carcinoma: A cytological case report. Med J DY Patil Vidyapeeth [serial online] 2018 [cited 2020 Dec 2];11:449-51. Available from: https://www.mjdrdypv.org/text.asp?2018/11/5/449/240378
| Introduction|| |
Undifferentiated thyroid carcinoma (UTC) is a rare highly malignant tumor that arises from the follicular cells of the thyroid gland. It is defined by the WHO as a highly malignant tumor wholly or partially composed of undifferentiated cells that retain features indicative of an epithelial origin, on immunohistochemical or ultrastructural ground. It usually affects elderly people, with a mean age in the mid-60s, and shows a female predominance. It constitutes <5% of clinically recognized thyroid malignancies, but it accounts for more than half of the deaths for thyroid cancer, with a mortality rate that is over 90% and a mean survival of 6 months after the diagnosis.
| Case Report|| |
A 70-year-old female patient presented with a diffuse neck swelling for 1 month, associated with dyspnea. On examination, the swelling was fixed, had diffuse margins, was hard in consistency, and measured 6 cm × 5 cm. Thyroid function tests revealed a euthyroid status.
FNAC smears performed from the thyroid swelling were cellular comprising of highly pleomorphic cells arranged diffusely, in clusters and singly scattered. Cells were large, having round-to-oval nuclei, coarse chromatin, prominent nucleoli, and moderate-to-abundant cytoplasm [Figure 1] and [Figure 2]. Few bizarre cells and multinucleated giant cells were also seen in the background of inflammatory cells [Figure 3] and [Figure 4]. The final diagnosis of UTC was made. Follow-up details were not available as the patient left without intimation.
|Figure 1: Smears show highly pleomorphic large cells arranged diffusely and singly scattered with round-to-oval nuclei, coarse chromatin, prominent nucleoli, and moderate-to-abundant cytoplasm in the background of inflammatory cells (PAP, ×40)|
Click here to view
|Figure 2: Smears show pleomorphic large cells with hyperchromatic nuclei and increased mitotic activity (PAP, ×40)|
Click here to view
|Figure 3: Smears show highly pleomorphic cells in cluster admixed with multinucleate giant cell in the inflammatory hemorrhagic background (PAP, ×40)|
Click here to view
|Figure 4: Smears show tumor cells individually scattered and admixed with multinucleate giant cell (PAP, ×40)|
Click here to view
| Discussion|| |
UTC is also known as undifferentiated, dedifferentiated, or anaplastic carcinoma. UTC is an uncommon, aggressive tumor which constitutes 2%–5% of all thyroid tumors, but it is invariably fatal.
It may occur from dedifferentiation of existing well-differentiated carcinoma, but such transformation is not frequently seen and is reported in <2% of cases. All the subtypes of thyroid carcinoma can progress to UTC, but papillary and follicular carcinoma are the most common types to undergo this transformation.
UTC is seen in elderly, with peak incidence in sixth to seventh decades and is more common in females (55%–77%)., Patients usually present with rapidly growing neck mass with extrathyroid extension, leading to hoarseness of voice, dysphagia, and dyspnea.,
FNAC provides early diagnosis, and sensitivity of FNAC for thyroid malignancy ranges from 61% to 97.7%.,, On FNAC, three major patterns are recognized: giant cell, spindle cell, and squamoid pattern. Majority of the cases show admixture of these patterns. Regardless of the type, cells have highly pleomorphic nuclei, coarsely granular clumped chromatin, prominent nucleoli, and occasional intranuclear inclusions. Multinucleation, multilobation, and numerous mitotic figures are common.,
FNAC smears are usually composed of a pleomorphic cellular population in a necrotic background. The tumor cells are bizarre, oval-to-spindle shaped, dyscohesive elements showing anisocytosis and irregular sometimes multiple nuclei. Giant cells are characterized by deep pleomorphism, having bizarre sometimes multiple hyperchromatic nuclei; abundant eosinophilic cytoplasm; and a plump, oval, or round shape [Figure 3] and [Figure 4]. They are typically interspersed among smaller mononuclear tumor cells with similar cytoplasmic features showing a solid architecture. The presence of striking pleomorphism, high mitotic activity, and necrosis is strongly suggestive for UTC.
Variable immunophenotype is seen in UTC. Around 40%–100% of cases show immunoreactivity to cytokeratin. Spindle cell component expresses vimentin, whereas squamoid cells express epithelial membrane antigen and carcinoembryonic antigen. Interspersed nonneoplastic thyroid follicular epithelial cells may give false positivity to thyroglobulin. UTC cells are not reactive for TTF [Thyroid transcription factor] 1, calcitonin, thyroglobulin, and RET/PTC [rearranged during transfection/ papillary histotype] oncoprotein. PAX8 has a useful role and is positive in 79% of UTCs and in up to 92% of UTCs showing squamoid features.
| Conclusion|| |
Anaplastic carcinoma of thyroid is an uncommon but markedly aggressive tumor. Transformation from preexisting carcinoma is rare and reported in <2% of cases. FNAC plays a pivotal role in making early and accurate diagnosis facilitating early treatment.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Alwani M, Rathod GB. Diagnosis of anaplastic thyroid carcinoma on fine needle aspiration cytology – A rare case report. IAIM 2015;2:183-7.
Ragazzi M, Ciarrocchi A, Sancisi V, Gandolfi G, Bisagni A, Piana S, et al.
Update on anaplastic thyroid carcinoma: Morphological, molecular, and genetic features of the most aggressive thyroid cancer. Int J Endocrinol 2014;2014:790834.
Nagpal R, Kaushal M, Kumar S. Cytological diagnosis of an uncommon high grade malignant thyroid tumor: A case report. JCDR 2017;11:3-5.
Piromchai P, Ratanaanekchai T, Kasemsiri P. Diagnosis and treatment of anaplastic thyroid carcinoma. Int J Clin Med 2012;3:69-73.
Pitt SC, Moley JF. Medullary, anaplastic, and metastatic cancers of the thyroid. Semin Oncol 2010;37:567-79.
Feng G, Laskin WB, Chou PM, Lin X. Anaplastic thyroid carcinoma with rhabdoid features. Diagn Cytopathol 2015;43:416-20.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]