Diagnosis and Treatment of Metastases to the Thyroid Gland: a Meta-Analysis.
The thyroid is a rare site of clinically detectable tumor metastases; even though the gland is a highly vascularized structure, the frequency of metastases in the routine practice is less than 0.2% of all thyroid malignancies. The purpose of our meta-analysis is to evaluate the frequency of metastatic diffusion from other primary tumors to the thyroid gland and to suggest the best possible treatment through an evidence-based study. Relevant studies were identified by searching the following databases: PubMed, Scopus, and Web of Science. We selected all English-written articles published from 1995 to 2015. Studies were considered eligible if they reported the timing of metastatic spread and the site of the primary tumor in respect to the diaphragmatic region. Case reports were not included. Twenty-eight studies accounted for 514 patients. The rate of metachronous metastases was 69%. Fifty-three percent of primaries originated from the infradiaphragmatic region. Fine needle aspiration biopsy (FNAB) was done in 154 patients and 195 patients were treated mostly with surgery. A prevalence of primary tumors from the infradiaphragmatic region and of metachronous metastases was observed. Knowledge of the clinical history and the ancillary techniques can improve the sensitivity and accuracy of FNAB. Thyroidectomy may be considered a more effective treatment than radio-chemotherapy.
Division of Anatomic Pathology and Histology Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Patrizia
P
Straccia
Division of Anatomic Pathology and Histology Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Claudia
C
Mosseri
Division of Anatomic Pathology and Histology Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Chiara
C
Brunelli
Division of Anatomic Pathology and Histology Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Esther Diana
ED
Rossi
Division of Endocrine Surgery, Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Celestino Pio
CP
Lombardi
Division of Endocrinology, Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy.
Alfredo
A
Pontecorvi
Division of Anatomic Pathology and Histology Catholic University of Sacred Heart, Foundation "Agostino Gemelli" University Hospital, Largo Francesco Vito 1, 00168, Rome, Italy. guidofadda@rm.unicatt.it.
Guido
G
Fadda
D006801:Humans; D013964:Thyroid Neoplasms / Q000556:secondary* / Q000628:therapy*
Diagnosis; Meta-analysis; Metastasis; Surgery; Thyroid neoplasm