A Case Report Demonstrating How the Clinical Presentation of the Diffuse Sclerosing Variant of Papillary Thyroid Carcinoma Can Mimic Benign Riedel’s Thyroiditis

Abstract EN

A 44-year-old female presented with a two-month history of a neck mass, sore throat, hoarseness, and intermittent dysphagia.

Examination revealed a “woody” hard swelling arising from the right lobe of the thyroid.

Clinically this was felt to be classical Riedel’s thyroiditis (RT).

Thyroid ultrasound showed a diffusely enlarged, low echogenicity thyroid with a multinodular goitre.

An abnormal nodule extending across the isthmus was noted.

Following a nondiagnostic fine needle aspiration, an open core biopsy was performed.

This showed dense sclerotic fibrosis punctuated by nodular mononuclear inflammatory cells, which obscured follicular epithelial cells consistent with a fibrosing thyroiditis (Riedel’s thyroiditis).

A biopsy of pretracheal lymph nodes showed a sclerotic process throughout the lymph nodes and nests of epithelium bands with squamous differentiation obscured by a fibrous process.

These findings raised the differential diagnosis of diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) with metastasis to lymph nodes.

A total thyroidectomy and pretracheal lymph node dissection were performed.

The final histological diagnosis was DSV-PTC.

When managing a patient with presumed RT it is important to consider malignancy in the differential.

DSV-PTC is one of the more aggressive forms of thyroid cancer but with early diagnosis and appropriate treatment patients may have excellent outcomes.