Myxoid lipoadenoma of parathyroid gland: a case report and literature review

Department of Pathology, New York University School of Medicine and NYU Cancer Institute, New York Harbor Healthcare System, New York, NY 10010, USA.
Annals of Diagnostic Pathology (Impact Factor: 1.12). 11/2006; 10(5):294-6. DOI: 10.1016/j.anndiagpath.2005.09.005
Source: PubMed


Myxoid lipoadenoma of the parathyroid gland is a rare variant of parathyroid adenoma. We present the case of a 40-year-old man with asymptomatic hypercalcemia who underwent surgical removal of a parathyroid adenoma. Histologically, the tumor consisted of monomorphous round-to-oval chief cells arranged in several architectural patterns including solid sheet-like, trabecular, and follicular. The tumor stroma was prominently myxoid with interspersed mature adipose tissue. Immunohistochemistry confirmed expression of thyroid transcription factor and parathyroid hormone by all tumor cells and a low proliferation rate with a Ki-67 labeling index of at most 5%. Although the lesion exhibited characteristics that have been previously associated with "atypical parathyroid adenoma," such as dense fibrous bands within the tumor and a trabecular growth pattern, there was no further evidence, neither histologically nor clinically, for malignant behavior of the tumor.

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