Fine needle aspiration of giant cell tumor involving thyroid gland: A case report of an unprecedented entity

Giant cell tumor of soft tissue involving thyroid gland: a case report and review of the literature

BACKGROUND

Giant cell tumor of soft tissue is a low malignant uncommon neoplasm, with histologic features and immunophenotype similar to its bone counterpart. Primary giant cell tumor of soft tissue in the thyroid gland is considered an exceedingly rare entity.

CASE PRESENTATION

We describe a case of primary thyroid giant cell tumor of soft tissue in a 69-year-old Chinese female patient. Neck ultrasonography showed a 19 mm × 12 mm × 5 mm nodule with heterogeneous echo and clear boundary located within the left thyroid. Histopathological examination revealed that the neoplasm was composed of two morphological components, mononuclear cells admixed with multinucleated osteoclast-like giant cells. Immunohistochemically, the tumor cells were positive for CD68 and vimentin, but were negative for epithelial membrane antigen, cytokeratin, and additional muscle markers. She underwent left unilateral thyroidectomy, and total thyroidectomy was performed for local recurrence 3 months later. The patient remained well without recurrence or metastasis following up for 12 months.

CONCLUSION

The significance of this case lies in its rarity, the challenge of preoperative clinical diagnosis, and the differential diagnosis with other malignancies.

Giant cell tumor of thyroid cartilage: A diagnostic dilemma on aspiration cytology

Giant cell tumor of the larynx is an uncommon entity with only 44 cases reported in the literature. These tumors occur most commonly in the epiphysis of the long bones of female patients in third decade. Here in we report a case of 23 years old male patient who presented with an anterior neck swelling since past 4 months. Ultrasound and computed tomography of neck revealed a heterogenously enhancing lesion involving posteroinferior half of right thyroid cartilage with extension into the extra laryngeal strap muscle and intralaryngeal right true vocal cord and false vocal cord. The findings were suggestive of a neoplastic cartilagenous lesion. A fine needle aspiration of the right anterior neck mass was performed which showed many mononuclear cells along with multinucleated osteoclast type giant cells. No thyroid follicular cells or inflammatory cells were seen. A diagnosis of giant cell tumor of the thyroid cartilage was rendered on cytology. A biopsy was subsequently performed for the patient which confirmed the same. Hence, although giant cell tumor of the larynx is a rare entity, with very few cases reported in the literature, these tumors should be included in the differential diagnosis of giant cell lesions of the neck and aspiration cytology can offer an accurate and quick diagnosis in such cases.

Giants and monsters: Unexpected characters in the story of cancer recurrence

Polyploid giant cancer cells (PGCC) constitute a dangerous subpopulation of cancer cells and are a driving force in cancer recurrence. These unique cells arise from diploid tumor cells in response to stress encountered in the tumor microenvironment or during cancer therapy. PGCC are greatly dedifferentiated, acquire pluripotency, and are able to replicate through a form of asymmetric division called neosis, which results in new populations that are themselves able to differentiate into new cell types or to re-establish tumors. Progeny tend to be more genetically unstable than the founding population due to the dysregulation required to transition through a PGCC state. Therefore, cancers that escape stressors through this mechanism tend to re-emerge with a more aggressive phenotype that is therapy resistant. This review focuses on the clinical significance of PGCC, the need for standardized nomenclature and molecular markers, as well as possible avenues to develop therapies aimed at PGCC and the process of neosis. The biology underlying the development of PGCC including cell cycle checkpoint dysregulation, stress responses, dedifferentiation, stemness and epithelial-mesenchymal transition is discussed.

Mucinous breast carcinoma metastatic to thyroid gland: Report of a case diagnosed by fine-needle aspiration cytology

Mucinous breast cancer is a slow-growing neoplasm, which has fewer lymph node metastases and favorable prognosis compared with invasive breast cancer no special type. The hematogenous spread of breast mucinous carcinoma is very rare. Though breast cancer involving thyroid has been reported before, there is still no report about thyroid metastatic breast mucinous carcinoma in the literature. Recently by performing thyroid fine-needle aspiration, a 58-year-old woman who had breast cancer 13 years ago was diagnosed as thyroid metastatic mucinous breast carcinoma, cellular variant with neuroendocrine differentiation. For this patient, the thyroid was the only involved site without widespread metastatic diseases, so thyroidectomy and the right cervical lymph nodes dissection were performed to make better survival. As a result, the patient had not shown any signs of recurrence 9 months after the thyroid surgery.