A delayed teflonoma of the neck simulating a thyroid neoplasm.

Pseudotumoral granulomatous foreign body reaction to Teflon particles is a rare complication of intracordal Teflon paste injection for unilateral vocal cord paralysis. We report a case of pseudotumor of the thyroid area, which appeared 3 years after intracordal Teflon paste injection and presented as a cold thyroid nodule. At frozen section examination the presence of a giant-cell foreign body granuloma containing numerous refringent particles suggested a 'teflonoma'. The diagnosis was confirmed on permanent sections, after comparison of the intratissular particles with fresh Teflon paste, under conventional and polarized light. The histological and ultrastructural features of the lesion are presented and attention is drawn to the long delay between initial Teflon injection and the clinical manifestation of the lesion.