Papillary Thyroid Cancer in a Child with Progressive Transformation of Germinal Centers

Abstract

Objectives. To describe the presentation and management of a child with Progressive Transformation of Germinal Centers (PTGC), an uncommon condition characterized by significant persistent lymphadenopathy, who developed papillary thyroid carcinoma and to explore and review potential links between PTGC and neoplastic processes in the head and neck. Methods. Case presentation and literature review are used. Results. A 10-year-old female presented with a right parotid mass and cervical lymphadenopathy. Multiple biopsies revealed PTGC without malignancy. Two years later, she developed fatigue and weight gain, and a thyroid nodule was found. Fine needle aspiration was strongly suggestive of papillary thyroid carcinoma. The patient underwent total thyroidectomy and central neck dissection without surgical management of the longstanding right lateral neck lymphadenopathy. Final pathology confirmed papillary thyroid carcinoma. She was treated with radioactive iodine therapy postoperatively and remains free of disease at three years of follow-up. Conclusions. PTGC is considered a benign condition but has previously been associated with Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL). This is the first reported case of papillary thyroid cancer in a child with preexisting cervical PTGC and no defined risk factors for thyroid malignancy. No link has been established with thyroid carcinoma, but patients with PTGC may have a defect in immune surveillance that predisposes them to malignancy.

Figure 1

Positron Emission Tomography, Computed Tomography Scan. Fusion PET/CT demonstrating diffuse right cervical and left axillary lymphadenopathy.

Figure 2

PTGC microscopic examination. (a) PTGC, markedly enlarged lymphoid follicle infiltrated by small mature mantle zone lymphocytes with gradual replacement of germinal center (H&E, 4x). (b) Background of florid follicular lymphoid hyperplasia (H&E, 2x). (c) PTGC, germinal center replaced by small mature mantle zone lymphocytes (H&E, 20x). (d) Reactive germinal center with numerous tingle body macrophages (H&E, 20x).

Figure 3

Papillary thyroid cancer microscopic examination. (a) Papillary thyroid carcinoma. Circumscribed nodule with papillary and follicular architecture and background fibrous bands (H&E, 2x). (b) Nuclear crowding, oval to elongated nuclei with fine open chromatin, nuclear membrane irregularity, and nuclear grooves (H&E, 40x). (c) Lymph node showing metastatic papillary thyroid cancer (H&E, 4x). (d) Metastatic papillary thyroid cancer nuclear features (nuclear crowding, fine open chromatin pattern, nuclear grooves, and nuclear membrane irregularity) (H&E, 40x).