Tall cell variant of papillary carcinoma coexisting with chronic lymphocytic thyroiditis. A case report.

BACKGROUND

Recent studies have shown a correlation between lymphocytic thyroiditis and papillary carcinoma of the thyroid. It is thought that autoimmune thyroiditis could be a risk factor for the development of thyroid carcinoma, mainly for the papillary variant.

CASE

A 59-year-old female presented with a history of enlargement in the neck and five months of dysphagia. Clinical examination showed generalized expansion and an increase in the hardness of the thyroid gland. Hormonal outline showed subclinical hypothyroidism with serum levels of TSH slightly elevated (5 micrograms/dL; range, 0.25-4). Thyroglobulin antibodies and thyroperoxidase titers were moderately positive. Given these results, a diagnosis of chronic thyroiditis was made. Thyroid ultrasound scan showed diffuse gland irregularity and the presence of a solitary nodule (2.3 cm in diameter) localized in the right lobe. Fine needle aspiration biopsy (FNAB) of the nodule was performed under ultrasound guidance.

CONCLUSION

Although clinical and laboratory results supported the diagnosis of autoimmune thyroiditis only, FNAB of the nodular lesion provided evidence of a rare case of papillary carcinoma, tall cell variant, confirmed by histologic results.