Metastatic signet ring cell carcinoma presenting as a thyroid nodule: Report of a case with fine-needle aspiration cytology
- 1 January 2009
- journal article
- case report
- Published by Wiley in Diagnostic Cytopathology
- Vol. 38 (8), 597-602
- https://doi.org/10.1002/dc.21289
Abstract
Metastatic carcinomas to the thyroid are quite rare in daily cytology practice. However, when present they may produce a diagnostic dilemma, particularly when they share some morphologic similarities with primary thyroid lesions and when occurring in patients with occult malignant history. Herein, we report a case of metastatic gastric signet ring cell carcinoma to the thyroid. Our patient presented with an isolated right thyroid nodule, which was clinically considered to be a primary thyroid neoplasm. Fine-needle aspiration (FNA) cytology of the nodule revealed a cellular specimen with cohesive fragments and scattered individual neoplastic cells. The neoplastic cells had enlarged nuclei, fine chromatin, and inconspicuous nucleoli. Nuclear crowding, molding, and grooving were prominent. Intranuclear inclusion-like clearance was identified. Some tumor cells also had eccentric nuclei, creating a signet ring cell appearance. The colloid was scant. These cytological features may be seen in cases of papillary thyroid carcinoma or signet ring cell follicular adenoma; however, the presence of the signet ring cells is unusual in primary thyroid lesions and raises the possibility of a metastatic lesion to the thyroid. In our case, the tumor cells were positive for AE1/AE3, mucicarmine, and periodic acid-Schiff, but negative for thyroglobulin and thyroid transcription factor-1. The patient was also found to have a 3.7-cm mass in the distal esophagus/proximal stomach. Biopsy of this mass showed an invasive signet ring cell carcinoma. The purpose of our study is to discuss the cytological features and the differential diagnosis of this unusual thyroid FNA case.Keywords
This publication has 20 references indexed in Scilit:
- Metastasis to the thyroid diagnosed by fine‐needle aspiration biopsyClinical Endocrinology, 2005
- Metastatic bronchioloalveolar carcinoma presenting as a solitary thyroid nodule: Report of a case with fine‐needle aspiration cytopathologyDiagnostic Cytopathology, 2004
- Signet-Ring Follicular Adenoma of the Thyroid Diagnosed by Fine Needle AspirationActa Cytologica, 2004
- Metastatic renal cell carcinoma to the thyroid glandCancer, 2002
- Fine Needle Aspiration Cytology of Follicular Carcinoma with Clear Cell ChangeActa Cytologica, 2002
- Signet Ring Cell Adenoma of the Thyroid with Mucin PredominanceThyroid®, 1999
- Secondary Malignancy of the Thyroid Gland: A Case Report and Review of the LiteratureThyroid®, 1994
- Follicular Thyroid Carcinoma with Clear Cell Change Showing Unusual Ultrastructural FeaturesThe American Journal of Surgical Pathology, 1988
- Carcinoma Metastatic to the Thyroid: Prevalence and Diagnosis by Fine-Needle Aspiration CytologyThe American Journal of the Medical Sciences, 1987
- Incidence and Aetiology of Thyroid CarcinomaBMJ, 1961