US and CT findings of secondary neoplasms of the thyroid--a pictorial essay

Prevalencia de tumores metastásicos en la glándula tiroides. Revisión sistemática y metanálisis

Introducción y objetivo: Los tumores metastásicos en la glándula tiroides complican el diagnóstico, el tratamiento y el pronóstico del paciente. El objetivo es conocer la prevalencia de las metástasis en la glándula tiroides referida en la literatura médica y los tumores primarios que con más frecuencia metastatizan en la glándula tiroides. Método: Se realizó una revisión bibliográfica sistemática en las bases de datos de PubMed, La Biblioteca Cochrane y Scopus. Los artículos seleccionados se dividieron en dos grupos, series clínicas de pacientes en los que se hallaron metástasis en tiroides (grupo A) y series de hallazgos de metástasis en tiroides en autopsias (grupo B). Se realizó metanálisis de prevalencia para cada grupo de artículos siguiendo el modelo de efectos aleatorios. Resultados: La prevalencia en cada grupo con su índice de confianza al 95% fue 0.00479 (0.002-0.007) para el grupo A y 0.0362 (0.014-0.059) para el grupo B. La prevalencia de metástasis halladas en autopsias fue 7,58 veces mayor que en los estudios clínicos. En el grupo A la edad media fue 60.82 y en el grupo B 57.20. En ambos grupos las metástasis halladas en tiroides fueron más frecuentes en el sexo femenino. La localización del tumor primario fue diferente en ambos grupos, en el grupo A fue el cáncer de riñón y en el grupo B el cáncer de mama. La variabilidad de la prevalencia de metástasis en tiroides en los diferentes artículos de ambos grupos hace que este estudio tuviese una alta heterogeneidad (índice I2 y Q). Los funnel plot de ambos grupos indicaron alto sesgo de publicación. Discusión: La diferente prevalencia entre series clínicas y autopsias puede implicar que la detección de metástasis en tiroides en la clínica está infradiagnosticada. La razón de esto podría ser que las metástasis intratiroideas se presentan de forma asintomática siendo diagnosticadas como hallazgo casual en autopsias. En otras ocasiones se presentan como un nódulo tiroideo años después del tumor primario, lo que condiciona el diagnóstico. Conclusiones: La prevalencia de metástasis en tiroides es superior en las series de autopsias que en series clínicas (hasta 6.67 veces más frecuente en nuestro estudio). Las metástasis intratiroideas probablemente están infradiagnosticadas por cursar sin clínica siendo diagnosticadas como hallazgo casual en autopsias. Los tumores primarios más frecuentes fueron el riñón (series clínicas) y la mama (series de autopsias).

Colon cancer metastasis to the thyroid gland: report of a case with unique molecular profile

A high index of suspicion is needed when a patient presents with thyroid mass in the settings of an advanced CRC. Secondary thyroid malignancy should be considered unless proven otherwise. reatment should be determined considering extent of CRC metastasis, patient's general condition, and presence of local symptoms.

Sonographic features and ultrasonography-guided fine-needle aspiration of metastases to the thyroid gland

Purpose:

To evaluate the characteristic ultrasonographic (US) features of metastatic carcinoma to the thyroid, and how accurate US features and ultrasonography-guided fine-needle aspiration (US-FNA) are for the diagnosis of thyroid metastases.

Methods:

Twenty-three thyroid lesions in 23 patients (mean age, 66.7 years; range, 46 to 85 years) that had been diagnosed as thyroid metastases were included. The composition, echogenicity, margin, shape, presence of calcifications, underlying parenchymal echotexture, and vascularity were analyzed in US images of the thyroid metastases. Final US assessments were categorized into probably benign and suspicious malignancy. The presence of suspicious metastatic cervical lymph nodes was noted. The medical records, US-FNA cytology, and pathology reports of these patients were retrospectively reviewed.

Results:

Of the 23 thyroid lesions, the general US appearance was mass-forming in 21 (91.3%) and non-mass-forming in 2 (8.7%). All 23 lesions showed a solid tumor composition. Common US features among the 21 mass-forming thyroid metastases were hypoechogenicity (81.0%), non-circumscribed margins (90.5%), no calcifications (76.2%), and parallel shape (81.0%). Suspicious cervical lymph nodes were present in 18 patients (78.3%). Of the 23 lesions, 21 (91.3%) were classified as suspicious malignancy, and 2 (8.7%) as probably benign. US-FNA showed diagnostic results specific for metastases in 21 of the 22 patients (95.5%) who had undergone US-FNA.

Conclusion:

Common US features in thyroid metastasis were hypoechogenicity, non-circumscribed margins, no calcifications, parallel shape, and the presence of suspicious cervical lymph nodes. US-FNA can be effectively used in the diagnosis of thyroid metastasis, preventing unnecessary surgery.

Thyroid Metastasis of Gastric Cancer: A Rare Occasion With Poor Prognosis

A 68-year-old man was diagnosed as having advanced gastric cancer. Computed tomography showed a thyroid tumor with trachea deviation. This tumor exhibited mosaic echogenecity in ultrasonography. Signet-ring cell carcinoma was found by means of fine needle aspiration biopsy. This tumor gradually became swollen and the thyroid hormone levels in blood were increased without any clinical symptom. Shortly, he died from his illness in the 29th hospital day. Autopsy disclosed that the left lobe of the thyroid gland was highly invaded by malignant cells and that lymphogenic rather than angiogenic metastasis was highly probable. Thyroid metastasis of gastric cancer is extremely rare. The prognosis is very poor. Ultrasonography is a very useful modality especially when coupled with recently developed fine needle aspiration biopsy in differential diagnosis of thyroid tumors once malignancy is suspected. Therapeutic strategy largely depends on the nature of primary malignant tumor. If the tumor is slowly progressive such as renal cell carcinoma and breast cancer, extirpation of thyroid tumors may extend life expectancy. In conclusion, the metastatic thyroid tumor of gastric cancer is rare and shows poor prognosis. Fine needle aspiration biopsy under ultrasonography is strongly recommended as a useful diagnostic tool.

Metastasis to the thyroid gland: a case report and review of the literature

Metastatic cancer to the thyroid is uncommon. Although the thyroid is richly supplied with blood, there are a few reports of metastatic cancer spreading to this gland. The overall incidence in autopsy series has been quite varied, with rates from 1.2 to 24% of malignant tumors. Most of this metastases are not detected in clinical practice. The majority of these patients had widespread metastases and, as a result, had very short survival times. Although detection of metastases to the thyroid gland often indicates poor prognosis, aggressive surgical and medical treatment may be effective, especially for renal carcinoma. In this report, we present a case of renal carcinoma with thyroid metastases and a review of the literature.