Undifferentiated pleomorphic sarcoma of the thyroid: A case report and ƚiterature review

Abstract

This report describes a patient who presented with a large thyroid nodule and compressive symptoms. Immunohistochemical staining showed diffuse marked reactivity for vimentin and focal reactivity for CD68 and Ki‐67 that is compatible with primary undifferentiated pleomorphic sarcoma of the thyroid. This report emphasizes and discusses extremely rare thyroid cancer type.

Primary Undifferentiated Pleomorphic Thyroid Sarcoma Presenting as Superior Vena Cava Syndrome: A Case Report

“…Because of the rarity of these tumors, there is no consensus on the best treatment approach. However, surgery plays a central role in treating these tumors, with early and radical thyroidectomy typically associated with favorable outcomes, with a local recurrence rate of 27% within five years, compared to 86% seen with marginal resection [10,[12][13][14]. However, negative margin surgical resection is a difficult task given the complexity of head and neck anatomy.…”

“…The main subtypes of PTS include angiosarcoma, hemangioendothelioma, leiomyosarcoma, fibrosarcoma, osteosarcoma, liposarcoma, and undifferentiated pleomorphic sarcoma (UPS-T) [ 6 - 7 ]. UPS-T, previously known as malignant fibrous histiocytoma (MFH), is an extremely rare subtype of thyroid sarcoma without any defined cell differentiation [ 10 ]. As PTS are extremely rare, they have a high rate of misdiagnosis, especially as anaplastic thyroid carcinomas.…”

“…The gold standard for diagnosis of PTS tumors is histopathologic examination with immunohistochemical staining. On microscopic exam, PTS is classically composed of plump spindle cells arranged in a storiform pattern with high pleomorphism and giant cells [ 7 , 10 ].…”

“…While thyroid neoplasms generally have excellent outcomes with a five-year survival rate greater than 98.3% [ 1 - 2 ], PTS has a grim prognosis [ 7 , 10 ]. Because of the rarity of these tumors, there is no consensus on the best treatment approach.…”

“…In general, lymph node dissection is not recommended for these tumors, as PTS rarely metastasize to the regional lymph nodes [ 13 ]. Because of high recurrence rates associated with partial surgical resection alone, neoadjuvant and adjuvant chemoradiation is also often used to treat these tumors, despite a lack of statistically significant improvement in outcomes [ 10 ]. Nguyen et al analyzed 21 cases of primary undifferentiated pleomorphic sarcoma treated with surgery and adjuvant chemoradiation.…”