An exceptionally rare case of metastatic osteoclast‐like giant cell–rich variant of anaplastic thyroid carcinoma: A diagnostic challenge

Abstract

Anaplastic thyroid carcinoma (ATC; undifferentiated thyroid carcinoma) is a rare and perpetually fatal malignant tumour accounting for 1 to 2 percent of all thyroid gland neoplasms. It usually affects elderly people, with a mean age in the mid 60s, and shows a female predominance. 1 The osteoclast-like giant cell-rich variant of anaplastic thyroid carcinoma is extremely rare and is characterised by the presence of a large number of multinucleated giant cells resembling osteoclasts. We report here this unusual tumour

Pitfalls in soft tissue cytopathology

“…77 cytomorphological pattern. 81 The presence of rhabdomyoblasts can provide a useful clue in the diagnostic process. If they are observed, the tumour could be triaged for immunostains of skeletal muscle differentiation, including desmin, myogenin and myoD1, for consideration of a pleomorphic rhabdomyosarcoma.…”

“…However, there are certain mimics and pitfalls in the diagnosis, and the specific diagnosis often relies on ancillary testing 3,80 . A diagnosis of pleomorphic sarcoma should be considered after ruling out a carcinoma, including the ones that have multinucleate giant cells and melanoma, which can mimic tumours across any cytomorphological pattern 81 . The presence of rhabdomyoblasts can provide a useful clue in the diagnostic process.…”

Undifferentiated carcinoma of the liver with osteoclast-like giant cells: a case report and literature review

“…Carcinomas with osteoclast-like giant cells (OGCs) occasionally occur in a variety of sites such as pancreatic [ 3 ], ampullary [ 4 ], duodenal [ 5 ], gastric [ 6 ], gallbladder [ 7 ], thyroid [ 8 ], breast [ 9 ], lung [ 10 ], urinary bladder [ 11 ], ureter [ 12 ], kidney [ 13 ], cutaneous [ 14 ], parotid gland [ 15 ], renal pelvis [ 16 ], salivary [ 17 ], ovary [ 18 ], and liver [ 19 ], with pancreatic tumors being the most common. The presence of OGCs in HCC is extremely rare, and there have been relatively few clinical reports.…”

“…Carcinomas with osteoclast-like giant cells (OGCs) occasionally occur in a variety of sites such as pancreatic [3], ampullary [4], duodenal [5], gastric [6], gallbladder [7], thyroid [8], breast [9], lung [10], urinary bladder [11], ureter [12], kidney [13], cutaneous [14], parotid gland [15], renal pelvis [16], salivary [17], ovary [18],…”